Re: [AFMUG] battery nerd question

[Chris Fabien]

The term that got us cheap power was "unmetered CATV power supply".
They allow connection of a fixed capacity power supply unit with no
meter, just a small disconnect and drop a 120V 10AWG service and bill
us based on half of the power supply's nameplate capacity.

On Tue, Aug 15, 2023 at 3:45 PM Chuck McCown via AF  wrote:
>
> Some places have what is called a “street light tariff” that is about as low 
> as you can get.
>
>
>
> From: dmmoff...@gmail.com
> Sent: Tuesday, August 15, 2023 10:38 AM
> To: 'AnimalFarm Microwave Users Group'
> Subject: Re: [AFMUG] battery nerd question
>
>
> I can save you the suspense.  If you have access to electric that’ll be 
> cheaper than solar.  The problem is the need to run 24/7.  You have to design 
> around the December-January months.  I’m in NY State, and at our latitude we 
> only get a few hours of average production per day during those months.  And 
> obviously if it’s snowing for a week you need to be able to ride through that 
> on mostly battery power.  Even with a modest load it takes a silly amount of 
> panels and batteries to stay up 24/7 in the winter.  More than you’d ever be 
> allowed to put on a utility pole.
>
>
>
> Talk to your electric co about the smallest service you can get.  Explain 
> what you’re trying to do and that your max load is very low.
>
> NYSEG normally doesn’t do less than 100A, but they made an exception and let 
> us do 60A.  You need a meter can, a service rated panel, a conduit up the 
> pole and a weatherhead.  Then you either have an outdoor outlet, or have an 
> outlet inside your enclosure.  You’ll want the smallest service they’ll let 
> you do because of the wire size on the service cable.  A 20A (if they’d allow 
> it) would only need a 12/3 with ground, and that’s up to 4800 Watts (240x20) 
> so it’s still more than you’d ever need.   A 12/3 is way cheaper than a 100A 
> service entrance cable.
>
>
>
> My figure is 8 years old, and obviously there’s been inflation since then, 
> but I went to the same contractor who does electric installs for the cable 
> company and they quoted me about $1000.  Even if it’s 3x that for you today 
> you’d still never beat that with a solar installation even if they’d let you 
> do it.  And I’m not some knee-jerk anti-solar lunatic, I’m just saying I’ve 
> run the numbers and it doesn’t add up.   People do it when they’re off grid, 
> or when the electric service is unreliable in the area, or sometimes just for 
> the PR/marketing power of being “solar powered”.  Those are all fine reasons, 
> but doing it for cost savings isn’t going to work out.
>
>
>
> -Adam
>
>
>
>
>
> From: AF  On Behalf Of Steve Jones
> Sent: Tuesday, August 15, 2023 10:27 AM
> To: AnimalFarm Microwave Users Group 
> Subject: Re: [AFMUG] battery nerd question
>
>
>
> we have a dozen or so, but are looking at pole mount micropops (our own 
> poles). We are losing a grain elevator site because they decommissioned the 
> elevator and theres no real options for the customers in some of the areas. 
> Im just trying to get to something we can get solar power with enough battery 
> to last through overcast. So Im calculating per battery runtimes, then will 
> look at number of batteries we would need to survive vs paying for a ROW 
> meter vs losing the customers. Just have to get to the cost per customer to 
> retain them and the benefit gained per pole
>
>
>
>
>
> On Tue, Aug 15, 2023 at 8:53 AM Brian Webster  
> wrote:
>
> How many of the batteries do you have? Do you need any voltages other than 
> the 48 volts? If you have 4 batteries and only need 48 volts then wire them 
> in series and not have to deal with the converter.
>
>
>
> Thank you,
>
> Brian Webster
>
>
>
>
>
> From: AF [mailto:af-boun...@af.afmug.com] On Behalf Of dmmoff...@gmail.com
> Sent: Tuesday, August 15, 2023 6:59 AM
> To: 'AnimalFarm Microwave Users Group'
> Subject: Re: [AFMUG] battery nerd question
>
>
>
> *You’re around C/30 which should be on the high end of capacity.
>
> Lower load usually means a little extra capacity out of the battery.  I 
> realized that sentence might have been ambiguous.
>
>
>
>
>
> From: dmmoff...@gmail.com 
> Sent: Tuesday, August 15, 2023 6:56 AM
> To: 'AnimalFarm Microwave Users Group' 
> Subject: RE: [AFMUG] battery nerd question
>
>
>
> You can do the whole thing in Watts.
>
>
>
> 12V * 150ah = 1800 Watt-hours
>
> 1800Wh / 50W = 36 hours
>
>
>
> If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
> 0.95).
>
> There’s usually an efficiency curve for the device based on load and 
> temperature so it wouldn’t be 95% in all circumstances.  Your system should 
> be drawing less than 5A off the battery, and if your multimeter has a 10A 
> fuse like most do, then you could put the meter in line and actually measure 
> the amperage before and after the converter.  Then you’d know for sure.
>
>
>
> And the battery’s total capacity will have a curve based on C-rate so there’s 
> some variability 

Re: [AFMUG] battery nerd question

[Robert]

I read about one of those that is already pre-packaged in a lead 
coffin.  It does have a bad history with 3 kills and about 1/2 dozen 
sickened...   You have to provide the deuce and 1/2 with the shielded 
drivers compartment.


On 8/15/23 4:52 PM, Chuck McCown via AF wrote:
I got some old Russian thermo electric generators that are self 
heating.  They are pretty good for things like this.  You will have to 
pick them up though, Sakhalin Island.

Best Regards,
Chuck McCown

McCown Technology Corporation
8401 N Commerce Dr
Lake Point, Utah 84074
801-250-9503 Office
435-830-4306 Cell
www.mccowntech.com
www.microtrench.pro
www.terabitnetworks.com
*From:* Dennis Burgess
*Sent:* Tuesday, August 15, 2023 2:36 PM
*To:* AnimalFarm Microwave Users Group
*Subject:* Re: [AFMUG] battery nerd question

You can use 9dot and do your power control, dc in on solar panels 48 
volt system..    Just another option, lots of reporting and metering 
there..


*LTI-Full_175px*

*Dennis Burgess, Mikrotik Certified Trainer
MTCNA, MTCRE, MTCWE, MTCTCE, MTCINE, MTCSE, HE IPv6 Sage, Cambium ePMP 
Certified *


Author of "Learn RouterOS- Second Edition”

*Link Technologies, Inc*-- Mikrotik & WISP Support Services

*Office*: 314-735-0270  Website: http://www.linktechs.net 



Need to Automate MikroTik Backups: https://cloud.linktechs.net 



Create Wireless Coverage’s with www.towercoverage.com 



*From:* AF  *On Behalf Of *Josh Luthman
*Sent:* Tuesday, August 15, 2023 11:36 AM
*To:* AnimalFarm Microwave Users Group 
*Subject:* Re: [AFMUG] battery nerd question

OMG get meters.  The panels and batteries will cost more up front and 
they won't last as long.  Solar sucks here in Ohio, it's only going to 
be worse where you're at.


On Tue, Aug 15, 2023 at 11:54 AM Steve Jones  wrote:

we have a dozen or so, but are looking at pole mount micropops
(our own poles). We are losing a grain elevator site because they
decommissioned the elevator and theres no real options for the
customers in some of the areas. Im just trying to get to something
we can get solar power with enough battery to last through
overcast. So Im calculating per battery runtimes, then will look
at number of batteries we would need to survive vs paying for a
ROW meter vs losing the customers. Just have to get to the cost
per customer to retain them and the benefit gained per pole

On Tue, Aug 15, 2023 at 8:53 AM Brian Webster
 wrote:

How many of the batteries do you have? Do you need any
voltages other than the 48 volts? If you have 4 batteries and
only need 48 volts then wire them in series and not have to
deal with the converter.

Thank you,

Brian Webster

*From:*AF [mailto:af-boun...@af.afmug.com] *On Behalf Of
*dmmoff...@gmail.com
*Sent:* Tuesday, August 15, 2023 6:59 AM
*To:* 'AnimalFarm Microwave Users Group'
*Subject:* Re: [AFMUG] battery nerd question

*You’re around C/30 which should be on the high end /of
capacity/.

Lower load usually means a little extra capacity out of the
battery.  I realized that sentence might have been ambiguous.

*From:* dmmoff...@gmail.com 
*Sent:* Tuesday, August 15, 2023 6:56 AM
*To:* 'AnimalFarm Microwave Users Group' 
*Subject:* RE: [AFMUG] battery nerd question

You can do the whole thing in Watts.

12V * 150ah = 1800 Watt-hours

1800Wh / 50W = 36 hours

If they’re telling me 95% efficiency, I’d assume 50W out needs
53W in (50 / 0.95).

There’s usually an efficiency curve for the device based on
load and temperature so it wouldn’t be 95% in all
circumstances. Your system should be drawing less than 5A off
the battery, and if your multimeter has a 10A fuse like most
do, then you could put the meter in line and actually measure
the amperage before and after the converter.  Then you’d know
for sure.

And the battery’s total capacity will have a curve based on
C-rate so there’s some variability there too.  Usually it
lasts longer when you’re drawing lower amperage.  You’re
around C/30 which should be on the high end.

Age and maintenance of the battery affect runtime as well.  If
I want 6 hours of runtime then I plan Ah for 12 hours runtime.
When my batteries are halfway toasted I’m still getting useful
life out of them.

*From:* AF  *On Behalf Of *Steve Jones
*Sent:* Monday, August 14, 2023 9:57 PM
*To:* AnimalFarm Microwave Users Group 
*Subject:* [AFMUG] battery nerd question

Just trying to cipher runtimes

I have on hand 150ah 12 volt batteries, so thats what id be
looking to use.

Excluding the conversion loss of a 12v to 48v step up
converter is the 

Re: [AFMUG] battery nerd question

[Chuck McCown via AF]

I got some old Russian thermo electric generators that are self heating.  They 
are pretty good for things like this.  You will have to pick them up though, 
Sakhalin Island.  

Best Regards,
Chuck McCown

McCown Technology Corporation 
8401 N Commerce Dr
Lake Point, Utah 84074
801-250-9503 Office
435-830-4306 Cell
www.mccowntech.com
www.microtrench.pro
www.terabitnetworks.com

From: Dennis Burgess 
Sent: Tuesday, August 15, 2023 2:36 PM
To: AnimalFarm Microwave Users Group 
Subject: Re: [AFMUG] battery nerd question

You can use 9dot and do your power control, dc in on solar panels 48 volt 
system..Just another option, lots of reporting and metering there..

 

 



Dennis Burgess, Mikrotik Certified Trainer
MTCNA, MTCRE, MTCWE, MTCTCE, MTCINE, MTCSE, HE IPv6 Sage, Cambium ePMP 
Certified 

Author of "Learn RouterOS- Second Edition” 

Link Technologies, Inc -- Mikrotik & WISP Support Services 

Office: 314-735-0270  Website: http://www.linktechs.net 

Need to Automate MikroTik Backups:  https://cloud.linktechs.net 

Create Wireless Coverage’s with www.towercoverage.com 

 

From: AF  On Behalf Of Josh Luthman
Sent: Tuesday, August 15, 2023 11:36 AM
To: AnimalFarm Microwave Users Group 
Subject: Re: [AFMUG] battery nerd question

 

OMG get meters.  The panels and batteries will cost more up front and they 
won't last as long.  Solar sucks here in Ohio, it's only going to be worse 
where you're at.

 

On Tue, Aug 15, 2023 at 11:54 AM Steve Jones  wrote:

  we have a dozen or so, but are looking at pole mount micropops (our own 
poles). We are losing a grain elevator site because they decommissioned the 
elevator and theres no real options for the customers in some of the areas. Im 
just trying to get to something we can get solar power with enough battery to 
last through overcast. So Im calculating per battery runtimes, then will look 
at number of batteries we would need to survive vs paying for a ROW meter vs 
losing the customers. Just have to get to the cost per customer to retain them 
and the benefit gained per pole

   

   

  On Tue, Aug 15, 2023 at 8:53 AM Brian Webster  
wrote:

How many of the batteries do you have? Do you need any voltages other than 
the 48 volts? If you have 4 batteries and only need 48 volts then wire them in 
series and not have to deal with the converter.

 

Thank you,

Brian Webster

 

 

From: AF [mailto:af-boun...@af.afmug.com] On Behalf Of dmmoff...@gmail.com
Sent: Tuesday, August 15, 2023 6:59 AM
To: 'AnimalFarm Microwave Users Group'
Subject: Re: [AFMUG] battery nerd question

 

*You’re around C/30 which should be on the high end of capacity.  

Lower load usually means a little extra capacity out of the battery.  I 
realized that sentence might have been ambiguous.

 

 

From: dmmoff...@gmail.com  
Sent: Tuesday, August 15, 2023 6:56 AM
To: 'AnimalFarm Microwave Users Group' 
Subject: RE: [AFMUG] battery nerd question

 

You can do the whole thing in Watts.

 

12V * 150ah = 1800 Watt-hours

1800Wh / 50W = 36 hours

 

If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
0.95).   

There’s usually an efficiency curve for the device based on load and 
temperature so it wouldn’t be 95% in all circumstances.  Your system should be 
drawing less than 5A off the battery, and if your multimeter has a 10A fuse 
like most do, then you could put the meter in line and actually measure the 
amperage before and after the converter.  Then you’d know for sure.

 

And the battery’s total capacity will have a curve based on C-rate so 
there’s some variability there too.  Usually it lasts longer when you’re 
drawing lower amperage.  You’re around C/30 which should be on the high end.  

 

Age and maintenance of the battery affect runtime as well.  If I want 6 
hours of runtime then I plan Ah for 12 hours runtime. When my batteries are 
halfway toasted I’m still getting useful life out of them.

 

 

From: AF  On Behalf Of Steve Jones
Sent: Monday, August 14, 2023 9:57 PM
To: AnimalFarm Microwave Users Group 
Subject: [AFMUG] battery nerd question

 

Just trying to cipher runtimes

I have on hand 150ah 12 volt batteries, so thats what id be looking to use.

Excluding the conversion loss of a 12v to 48v step up converter is the math 
correct here?

12v 150ah=1800 watt hours
1800 watt hours at 48v = 37.5ah
50 watts of radio running 48v = 1.04 amps
37.5ah @ 1.04 amps = 32.77 hours runtime

 

does a step up that claims 95% efficiency mean 95% of the watt hours?

-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

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  AF@af.afmug.com
  http://af.afmug.com/mailman/listinfo/af_af.afmug.com




-- 
AF mailing 

Re: [AFMUG] battery nerd question

[Dennis Burgess]

You can use 9dot and do your power control, dc in on solar panels 48 volt 
system..Just another option, lots of reporting and metering there..


[LTI-Full_175px]
Dennis Burgess, Mikrotik Certified Trainer
MTCNA, MTCRE, MTCWE, MTCTCE, MTCINE, MTCSE, HE IPv6 Sage, Cambium ePMP Certified
Author of "Learn RouterOS- Second Edition”
Link Technologies, Inc -- Mikrotik & WISP Support Services
Office: 314-735-0270  Website: 
http://www.linktechs.net
Need to Automate MikroTik Backups:  https://cloud.linktechs.net
Create Wireless Coverage’s with www.towercoverage.com

From: AF  On Behalf Of Josh Luthman
Sent: Tuesday, August 15, 2023 11:36 AM
To: AnimalFarm Microwave Users Group 
Subject: Re: [AFMUG] battery nerd question

OMG get meters.  The panels and batteries will cost more up front and they 
won't last as long.  Solar sucks here in Ohio, it's only going to be worse 
where you're at.

On Tue, Aug 15, 2023 at 11:54 AM Steve Jones 
mailto:st...@togservice.com>> wrote:
we have a dozen or so, but are looking at pole mount micropops (our own poles). 
We are losing a grain elevator site because they decommissioned the elevator 
and theres no real options for the customers in some of the areas. Im just 
trying to get to something we can get solar power with enough battery to last 
through overcast. So Im calculating per battery runtimes, then will look at 
number of batteries we would need to survive vs paying for a ROW meter vs 
losing the customers. Just have to get to the cost per customer to retain them 
and the benefit gained per pole


On Tue, Aug 15, 2023 at 8:53 AM Brian Webster 
mailto:i...@wirelessmapping.com>> wrote:
How many of the batteries do you have? Do you need any voltages other than the 
48 volts? If you have 4 batteries and only need 48 volts then wire them in 
series and not have to deal with the converter.

Thank you,
Brian Webster


From: AF [mailto:af-boun...@af.afmug.com] On 
Behalf Of dmmoff...@gmail.com
Sent: Tuesday, August 15, 2023 6:59 AM
To: 'AnimalFarm Microwave Users Group'
Subject: Re: [AFMUG] battery nerd question

*You’re around C/30 which should be on the high end of capacity.
Lower load usually means a little extra capacity out of the battery.  I 
realized that sentence might have been ambiguous.


From: dmmoff...@gmail.com 
mailto:dmmoff...@gmail.com>>
Sent: Tuesday, August 15, 2023 6:56 AM
To: 'AnimalFarm Microwave Users Group' mailto:af@af.afmug.com>>
Subject: RE: [AFMUG] battery nerd question

You can do the whole thing in Watts.

12V * 150ah = 1800 Watt-hours
1800Wh / 50W = 36 hours

If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
0.95).
There’s usually an efficiency curve for the device based on load and 
temperature so it wouldn’t be 95% in all circumstances.  Your system should be 
drawing less than 5A off the battery, and if your multimeter has a 10A fuse 
like most do, then you could put the meter in line and actually measure the 
amperage before and after the converter.  Then you’d know for sure.

And the battery’s total capacity will have a curve based on C-rate so there’s 
some variability there too.  Usually it lasts longer when you’re drawing lower 
amperage.  You’re around C/30 which should be on the high end.

Age and maintenance of the battery affect runtime as well.  If I want 6 hours 
of runtime then I plan Ah for 12 hours runtime. When my batteries are halfway 
toasted I’m still getting useful life out of them.


From: AF mailto:af-boun...@af.afmug.com>> On Behalf Of 
Steve Jones
Sent: Monday, August 14, 2023 9:57 PM
To: AnimalFarm Microwave Users Group mailto:af@af.afmug.com>>
Subject: [AFMUG] battery nerd question

Just trying to cipher runtimes
I have on hand 150ah 12 volt batteries, so thats what id be looking to use.
Excluding the conversion loss of a 12v to 48v step up converter is the math 
correct here?
12v 150ah=1800 watt hours
1800 watt hours at 48v = 37.5ah
50 watts of radio running 48v = 1.04 amps
37.5ah @ 1.04 amps = 32.77 hours runtime

does a step up that claims 95% efficiency mean 95% of the watt hours?
--
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
--
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

Re: [AFMUG] battery nerd question

[Bill Prince]

Electric "can" be more cost effective unless you have to run wires a 
half kilometer or more. Our first remote POP was not quite a 1/4 mile 
from the nearest electric source, so we had to trench that distance, run 
conduit, and run relatively large gauge wires that distance. At that 
time, the cost of the copper alone exceeded the cost of doing it in 
solar. Today, the cost of the solar is a fraction of what it was then, 
and LFP batteries are now cost-competitive with SLA batteries.


That all said, we are at a convenient latitude (37°), and we have a 
pretty moderate climate, so heating and cooling are not a consideration, 
and we get at least 6 hours of sun on the shortest day of the year.


bp


On 8/15/2023 9:38 AM, dmmoff...@gmail.com wrote:


I can save you the suspense.  If you have access to electric that’ll 
be cheaper than solar.  The problem is the need to run 24/7.  You have 
to design around the December-January months.  I’m in NY State, and at 
our latitude we only get a few hours of average production per day 
during those months.  And obviously if it’s snowing for a week you 
need to be able to ride through that on mostly battery power.  Even 
with a modest load it takes a silly amount of panels and batteries to 
stay up 24/7 in the winter.  More than you’d ever be allowed to put on 
a utility pole.


Talk to your electric co about the smallest service you can get.  
Explain what you’re trying to do and that your max load is very low.


NYSEG normally doesn’t do less than 100A, but they made an exception 
and let us do 60A.  You need a meter can, a service rated panel, a 
conduit up the pole and a weatherhead.  Then you either have an 
outdoor outlet, or have an outlet inside your enclosure.  You’ll want 
the smallest service they’ll let you do because of the wire size on 
the service cable.  A 20A (if they’d allow it) would only need a 12/3 
with ground, and that’s up to 4800 Watts (240x20) so it’s still more 
than you’d ever need.   A 12/3 is way cheaper than a 100A service 
entrance cable.


My figure is 8 years old, and obviously there’s been inflation since 
then, but I went to the same contractor who does electric installs for 
the cable company and they quoted me about $1000.  Even if it’s 3x 
that for you today you’d still never beat that with a solar 
installation even if they’d let you do it.  And I’m not some knee-jerk 
anti-solar lunatic, I’m just saying I’ve run the numbers and it 
doesn’t add up.   People do it when they’re off grid, or when the 
electric service is unreliable in the area, or sometimes just for the 
PR/marketing power of being “solar powered”.  Those are all fine 
reasons, but doing it for cost savings isn’t going to work out.


-Adam

*From:* AF  *On Behalf Of *Steve Jones
*Sent:* Tuesday, August 15, 2023 10:27 AM
*To:* AnimalFarm Microwave Users Group 
*Subject:* Re: [AFMUG] battery nerd question

we have a dozen or so, but are looking at pole mount micropops (our 
own poles). We are losing a grain elevator site because they 
decommissioned the elevator and theres no real options for the 
customers in some of the areas. Im just trying to get to something we 
can get solar power with enough battery to last through overcast. So 
Im calculating per battery runtimes, then will look at number of 
batteries we would need to survive vs paying for a ROW meter vs losing 
the customers. Just have to get to the cost per customer to retain 
them and the benefit gained per pole


On Tue, Aug 15, 2023 at 8:53 AM Brian Webster 
 wrote:


How many of the batteries do you have? Do you need any voltages
other than the 48 volts? If you have 4 batteries and only need 48
volts then wire them in series and not have to deal with the
converter.

Thank you,

Brian Webster

*From:*AF [mailto:af-boun...@af.afmug.com] *On Behalf Of
*dmmoff...@gmail.com
*Sent:* Tuesday, August 15, 2023 6:59 AM
*To:* 'AnimalFarm Microwave Users Group'
*Subject:* Re: [AFMUG] battery nerd question

*You’re around C/30 which should be on the high end /of capacity/.

Lower load usually means a little extra capacity out of the
battery.  I realized that sentence might have been ambiguous.

*From:* dmmoff...@gmail.com 
*Sent:* Tuesday, August 15, 2023 6:56 AM
*To:* 'AnimalFarm Microwave Users Group' 
*Subject:* RE: [AFMUG] battery nerd question

You can do the whole thing in Watts.

12V * 150ah = 1800 Watt-hours

1800Wh / 50W = 36 hours

If they’re telling me 95% efficiency, I’d assume 50W out needs 53W
in (50 / 0.95).

There’s usually an efficiency curve for the device based on load
and temperature so it wouldn’t be 95% in all circumstances.  Your
system should be drawing less than 5A off the battery, and if your
multimeter has a 10A fuse like most do, then you could put the
meter in line and actually measure the amperage before and after
the converter.  Then you’d know for sure.

And the 

Re: [AFMUG] battery nerd question

[Chuck McCown via AF]

Some places have what is called a “street light tariff” that is about as low as 
you can get.  



From: dmmoff...@gmail.com 
Sent: Tuesday, August 15, 2023 10:38 AM
To: 'AnimalFarm Microwave Users Group' 
Subject: Re: [AFMUG] battery nerd question

I can save you the suspense.  If you have access to electric that’ll be cheaper 
than solar.  The problem is the need to run 24/7.  You have to design around 
the December-January months.  I’m in NY State, and at our latitude we only get 
a few hours of average production per day during those months.  And obviously 
if it’s snowing for a week you need to be able to ride through that on mostly 
battery power.  Even with a modest load it takes a silly amount of panels and 
batteries to stay up 24/7 in the winter.  More than you’d ever be allowed to 
put on a utility pole. 

 

Talk to your electric co about the smallest service you can get.  Explain what 
you’re trying to do and that your max load is very low.  

NYSEG normally doesn’t do less than 100A, but they made an exception and let us 
do 60A.  You need a meter can, a service rated panel, a conduit up the pole and 
a weatherhead.  Then you either have an outdoor outlet, or have an outlet 
inside your enclosure.  You’ll want the smallest service they’ll let you do 
because of the wire size on the service cable.  A 20A (if they’d allow it) 
would only need a 12/3 with ground, and that’s up to 4800 Watts (240x20) so 
it’s still more than you’d ever need.   A 12/3 is way cheaper than a 100A 
service entrance cable.

 

My figure is 8 years old, and obviously there’s been inflation since then, but 
I went to the same contractor who does electric installs for the cable company 
and they quoted me about $1000.  Even if it’s 3x that for you today you’d still 
never beat that with a solar installation even if they’d let you do it.  And 
I’m not some knee-jerk anti-solar lunatic, I’m just saying I’ve run the numbers 
and it doesn’t add up.   People do it when they’re off grid, or when the 
electric service is unreliable in the area, or sometimes just for the 
PR/marketing power of being “solar powered”.  Those are all fine reasons, but 
doing it for cost savings isn’t going to work out.

 

-Adam

 

 

From: AF  On Behalf Of Steve Jones
Sent: Tuesday, August 15, 2023 10:27 AM
To: AnimalFarm Microwave Users Group 
Subject: Re: [AFMUG] battery nerd question

 

we have a dozen or so, but are looking at pole mount micropops (our own poles). 
We are losing a grain elevator site because they decommissioned the elevator 
and theres no real options for the customers in some of the areas. Im just 
trying to get to something we can get solar power with enough battery to last 
through overcast. So Im calculating per battery runtimes, then will look at 
number of batteries we would need to survive vs paying for a ROW meter vs 
losing the customers. Just have to get to the cost per customer to retain them 
and the benefit gained per pole

 

 

On Tue, Aug 15, 2023 at 8:53 AM Brian Webster  wrote:

  How many of the batteries do you have? Do you need any voltages other than 
the 48 volts? If you have 4 batteries and only need 48 volts then wire them in 
series and not have to deal with the converter.

   

  Thank you,

  Brian Webster

   

   

  From: AF [mailto:af-boun...@af.afmug.com] On Behalf Of dmmoff...@gmail.com
  Sent: Tuesday, August 15, 2023 6:59 AM
  To: 'AnimalFarm Microwave Users Group'
  Subject: Re: [AFMUG] battery nerd question

   

  *You’re around C/30 which should be on the high end of capacity.  

  Lower load usually means a little extra capacity out of the battery.  I 
realized that sentence might have been ambiguous.

   

   

  From: dmmoff...@gmail.com  
  Sent: Tuesday, August 15, 2023 6:56 AM
  To: 'AnimalFarm Microwave Users Group' 
  Subject: RE: [AFMUG] battery nerd question

   

  You can do the whole thing in Watts.

   

  12V * 150ah = 1800 Watt-hours

  1800Wh / 50W = 36 hours

   

  If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
0.95).   

  There’s usually an efficiency curve for the device based on load and 
temperature so it wouldn’t be 95% in all circumstances.  Your system should be 
drawing less than 5A off the battery, and if your multimeter has a 10A fuse 
like most do, then you could put the meter in line and actually measure the 
amperage before and after the converter.  Then you’d know for sure.

   

  And the battery’s total capacity will have a curve based on C-rate so there’s 
some variability there too.  Usually it lasts longer when you’re drawing lower 
amperage.  You’re around C/30 which should be on the high end.  

   

  Age and maintenance of the battery affect runtime as well.  If I want 6 hours 
of runtime then I plan Ah for 12 hours runtime. When my batteries are halfway 
toasted I’m still getting useful life out of them.

   

   

  From: AF  On Behalf Of Steve Jones
  Sent: Monday, August 14, 2023 9:57 PM
  To: AnimalFarm 

Re: [AFMUG] battery nerd question

[dmmoffett]

I can save you the suspense.  If you have access to electric that’ll be cheaper 
than solar.  The problem is the need to run 24/7.  You have to design around 
the December-January months.  I’m in NY State, and at our latitude we only get 
a few hours of average production per day during those months.  And obviously 
if it’s snowing for a week you need to be able to ride through that on mostly 
battery power.  Even with a modest load it takes a silly amount of panels and 
batteries to stay up 24/7 in the winter.  More than you’d ever be allowed to 
put on a utility pole. 

 

Talk to your electric co about the smallest service you can get.  Explain what 
you’re trying to do and that your max load is very low.  

NYSEG normally doesn’t do less than 100A, but they made an exception and let us 
do 60A.  You need a meter can, a service rated panel, a conduit up the pole and 
a weatherhead.  Then you either have an outdoor outlet, or have an outlet 
inside your enclosure.  You’ll want the smallest service they’ll let you do 
because of the wire size on the service cable.  A 20A (if they’d allow it) 
would only need a 12/3 with ground, and that’s up to 4800 Watts (240x20) so 
it’s still more than you’d ever need.   A 12/3 is way cheaper than a 100A 
service entrance cable.

 

My figure is 8 years old, and obviously there’s been inflation since then, but 
I went to the same contractor who does electric installs for the cable company 
and they quoted me about $1000.  Even if it’s 3x that for you today you’d still 
never beat that with a solar installation even if they’d let you do it.  And 
I’m not some knee-jerk anti-solar lunatic, I’m just saying I’ve run the numbers 
and it doesn’t add up.   People do it when they’re off grid, or when the 
electric service is unreliable in the area, or sometimes just for the 
PR/marketing power of being “solar powered”.  Those are all fine reasons, but 
doing it for cost savings isn’t going to work out.

 

-Adam

 

 

From: AF  On Behalf Of Steve Jones
Sent: Tuesday, August 15, 2023 10:27 AM
To: AnimalFarm Microwave Users Group 
Subject: Re: [AFMUG] battery nerd question

 

we have a dozen or so, but are looking at pole mount micropops (our own poles). 
We are losing a grain elevator site because they decommissioned the elevator 
and theres no real options for the customers in some of the areas. Im just 
trying to get to something we can get solar power with enough battery to last 
through overcast. So Im calculating per battery runtimes, then will look at 
number of batteries we would need to survive vs paying for a ROW meter vs 
losing the customers. Just have to get to the cost per customer to retain them 
and the benefit gained per pole

 

 

On Tue, Aug 15, 2023 at 8:53 AM Brian Webster mailto:i...@wirelessmapping.com> > wrote:

How many of the batteries do you have? Do you need any voltages other than the 
48 volts? If you have 4 batteries and only need 48 volts then wire them in 
series and not have to deal with the converter.

 

Thank you,

Brian Webster

 

 

From: AF [mailto:af-boun...@af.afmug.com  ] On 
Behalf Of dmmoff...@gmail.com  
Sent: Tuesday, August 15, 2023 6:59 AM
To: 'AnimalFarm Microwave Users Group'
Subject: Re: [AFMUG] battery nerd question

 

*You’re around C/30 which should be on the high end of capacity.  

Lower load usually means a little extra capacity out of the battery.  I 
realized that sentence might have been ambiguous.

 

 

From: dmmoff...@gmail.com   mailto:dmmoff...@gmail.com> > 
Sent: Tuesday, August 15, 2023 6:56 AM
To: 'AnimalFarm Microwave Users Group' mailto:af@af.afmug.com> >
Subject: RE: [AFMUG] battery nerd question

 

You can do the whole thing in Watts.

 

12V * 150ah = 1800 Watt-hours

1800Wh / 50W = 36 hours

 

If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
0.95).   

There’s usually an efficiency curve for the device based on load and 
temperature so it wouldn’t be 95% in all circumstances.  Your system should be 
drawing less than 5A off the battery, and if your multimeter has a 10A fuse 
like most do, then you could put the meter in line and actually measure the 
amperage before and after the converter.  Then you’d know for sure.

 

And the battery’s total capacity will have a curve based on C-rate so there’s 
some variability there too.  Usually it lasts longer when you’re drawing lower 
amperage.  You’re around C/30 which should be on the high end.  

 

Age and maintenance of the battery affect runtime as well.  If I want 6 hours 
of runtime then I plan Ah for 12 hours runtime. When my batteries are halfway 
toasted I’m still getting useful life out of them.

 

 

From: AF mailto:af-boun...@af.afmug.com> > On Behalf 
Of Steve Jones
Sent: Monday, August 14, 2023 9:57 PM
To: AnimalFarm Microwave Users Group mailto:af@af.afmug.com> >
Subject: [AFMUG] battery nerd question

 

Just trying to 

Re: [AFMUG] battery nerd question

[Josh Luthman]

OMG get meters.  The panels and batteries will cost more up front and they
won't last as long.  Solar sucks here in Ohio, it's only going to be worse
where you're at.

On Tue, Aug 15, 2023 at 11:54 AM Steve Jones  wrote:

> we have a dozen or so, but are looking at pole mount micropops (our own
> poles). We are losing a grain elevator site because they decommissioned the
> elevator and theres no real options for the customers in some of the areas.
> Im just trying to get to something we can get solar power with enough
> battery to last through overcast. So Im calculating per battery runtimes,
> then will look at number of batteries we would need to survive vs paying
> for a ROW meter vs losing the customers. Just have to get to the cost per
> customer to retain them and the benefit gained per pole
>
>
> On Tue, Aug 15, 2023 at 8:53 AM Brian Webster 
> wrote:
>
>> How many of the batteries do you have? Do you need any voltages other
>> than the 48 volts? If you have 4 batteries and only need 48 volts then wire
>> them in series and not have to deal with the converter.
>>
>>
>>
>> Thank you,
>>
>> Brian Webster
>>
>>
>>
>>
>>
>> *From:* AF [mailto:af-boun...@af.afmug.com] *On Behalf Of *
>> dmmoff...@gmail.com
>> *Sent:* Tuesday, August 15, 2023 6:59 AM
>> *To:* 'AnimalFarm Microwave Users Group'
>> *Subject:* Re: [AFMUG] battery nerd question
>>
>>
>>
>> *You’re around C/30 which should be on the high end *of capacity*.
>>
>> Lower load usually means a little extra capacity out of the battery.  I
>> realized that sentence might have been ambiguous.
>>
>>
>>
>>
>>
>> *From:* dmmoff...@gmail.com 
>> *Sent:* Tuesday, August 15, 2023 6:56 AM
>> *To:* 'AnimalFarm Microwave Users Group' 
>> *Subject:* RE: [AFMUG] battery nerd question
>>
>>
>>
>> You can do the whole thing in Watts.
>>
>>
>>
>> 12V * 150ah = 1800 Watt-hours
>>
>> 1800Wh / 50W = 36 hours
>>
>>
>>
>> If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50
>> / 0.95).
>>
>> There’s usually an efficiency curve for the device based on load and
>> temperature so it wouldn’t be 95% in all circumstances.  Your system should
>> be drawing less than 5A off the battery, and if your multimeter has a 10A
>> fuse like most do, then you could put the meter in line and actually
>> measure the amperage before and after the converter.  Then you’d know for
>> sure.
>>
>>
>>
>> And the battery’s total capacity will have a curve based on C-rate so
>> there’s some variability there too.  Usually it lasts longer when you’re
>> drawing lower amperage.  You’re around C/30 which should be on the high
>> end.
>>
>>
>>
>> Age and maintenance of the battery affect runtime as well.  If I want 6
>> hours of runtime then I plan Ah for 12 hours runtime. When my batteries are
>> halfway toasted I’m still getting useful life out of them.
>>
>>
>>
>>
>>
>> *From:* AF  *On Behalf Of *Steve Jones
>> *Sent:* Monday, August 14, 2023 9:57 PM
>> *To:* AnimalFarm Microwave Users Group 
>> *Subject:* [AFMUG] battery nerd question
>>
>>
>>
>> Just trying to cipher runtimes
>>
>> I have on hand 150ah 12 volt batteries, so thats what id be looking to
>> use.
>>
>> Excluding the conversion loss of a 12v to 48v step up converter is the
>> math correct here?
>>
>> 12v 150ah=1800 watt hours
>> 1800 watt hours at 48v = 37.5ah
>> 50 watts of radio running 48v = 1.04 amps
>> 37.5ah @ 1.04 amps = 32.77 hours runtime
>>
>>
>>
>> does a step up that claims 95% efficiency mean 95% of the watt hours?
>> --
>> AF mailing list
>> AF@af.afmug.com
>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com
>>
> --
> AF mailing list
> AF@af.afmug.com
> http://af.afmug.com/mailman/listinfo/af_af.afmug.com
>
-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

Re: [AFMUG] battery nerd question

[Chuck McCown via AF]

For critical telecom I always used 20x the load power for panels and 2 weeks of 
battery autonomy for bad weather.
If you can access the site in bad weather to clear off snow or give it an aux 
charge you can go less.

I would still recommend 10 x on the panel size and at least 4 days of battery.  



From: Steve Jones 
Sent: Tuesday, August 15, 2023 8:26 AM
To: AnimalFarm Microwave Users Group 
Subject: Re: [AFMUG] battery nerd question

we have a dozen or so, but are looking at pole mount micropops (our own poles). 
We are losing a grain elevator site because they decommissioned the elevator 
and theres no real options for the customers in some of the areas. Im just 
trying to get to something we can get solar power with enough battery to last 
through overcast. So Im calculating per battery runtimes, then will look at 
number of batteries we would need to survive vs paying for a ROW meter vs 
losing the customers. Just have to get to the cost per customer to retain them 
and the benefit gained per pole 


On Tue, Aug 15, 2023 at 8:53 AM Brian Webster  wrote:

  How many of the batteries do you have? Do you need any voltages other than 
the 48 volts? If you have 4 batteries and only need 48 volts then wire them in 
series and not have to deal with the converter.



  Thank you,

  Brian Webster





  From: AF [mailto:af-boun...@af.afmug.com] On Behalf Of dmmoff...@gmail.com
  Sent: Tuesday, August 15, 2023 6:59 AM
  To: 'AnimalFarm Microwave Users Group'
  Subject: Re: [AFMUG] battery nerd question



  *You’re around C/30 which should be on the high end of capacity.  

  Lower load usually means a little extra capacity out of the battery.  I 
realized that sentence might have been ambiguous.





  From: dmmoff...@gmail.com  
  Sent: Tuesday, August 15, 2023 6:56 AM
  To: 'AnimalFarm Microwave Users Group' 
  Subject: RE: [AFMUG] battery nerd question



  You can do the whole thing in Watts.



  12V * 150ah = 1800 Watt-hours

  1800Wh / 50W = 36 hours



  If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
0.95).   

  There’s usually an efficiency curve for the device based on load and 
temperature so it wouldn’t be 95% in all circumstances.  Your system should be 
drawing less than 5A off the battery, and if your multimeter has a 10A fuse 
like most do, then you could put the meter in line and actually measure the 
amperage before and after the converter.  Then you’d know for sure.



  And the battery’s total capacity will have a curve based on C-rate so there’s 
some variability there too.  Usually it lasts longer when you’re drawing lower 
amperage.  You’re around C/30 which should be on the high end.  



  Age and maintenance of the battery affect runtime as well.  If I want 6 hours 
of runtime then I plan Ah for 12 hours runtime. When my batteries are halfway 
toasted I’m still getting useful life out of them.





  From: AF  On Behalf Of Steve Jones
  Sent: Monday, August 14, 2023 9:57 PM
  To: AnimalFarm Microwave Users Group 
  Subject: [AFMUG] battery nerd question



  Just trying to cipher runtimes

  I have on hand 150ah 12 volt batteries, so thats what id be looking to use.

  Excluding the conversion loss of a 12v to 48v step up converter is the math 
correct here?

  12v 150ah=1800 watt hours
  1800 watt hours at 48v = 37.5ah
  50 watts of radio running 48v = 1.04 amps
  37.5ah @ 1.04 amps = 32.77 hours runtime



  does a step up that claims 95% efficiency mean 95% of the watt hours?

  -- 
  AF mailing list
  AF@af.afmug.com
  http://af.afmug.com/mailman/listinfo/af_af.afmug.com




-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

Re: [AFMUG] battery nerd question

[Chuck McCown via AF]

Steve, 

Ah ratings are only good for one specific amp discharge.  More current = lower 
Ah.  Less current = higher Ah.  The full specs of a batter should give you a 
table or curves showing the different Ah capacity for different draws.  



From: dmmoff...@gmail.com 
Sent: Tuesday, August 15, 2023 4:59 AM
To: 'AnimalFarm Microwave Users Group' 
Subject: Re: [AFMUG] battery nerd question

*You’re around C/30 which should be on the high end of capacity.  

Lower load usually means a little extra capacity out of the battery.  I 
realized that sentence might have been ambiguous.

 

 

From: dmmoff...@gmail.com  
Sent: Tuesday, August 15, 2023 6:56 AM
To: 'AnimalFarm Microwave Users Group' 
Subject: RE: [AFMUG] battery nerd question

 

You can do the whole thing in Watts.

 

12V * 150ah = 1800 Watt-hours

1800Wh / 50W = 36 hours

 

If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
0.95).   

There’s usually an efficiency curve for the device based on load and 
temperature so it wouldn’t be 95% in all circumstances.  Your system should be 
drawing less than 5A off the battery, and if your multimeter has a 10A fuse 
like most do, then you could put the meter in line and actually measure the 
amperage before and after the converter.  Then you’d know for sure.

 

And the battery’s total capacity will have a curve based on C-rate so there’s 
some variability there too.  Usually it lasts longer when you’re drawing lower 
amperage.  You’re around C/30 which should be on the high end.  

 

Age and maintenance of the battery affect runtime as well.  If I want 6 hours 
of runtime then I plan Ah for 12 hours runtime. When my batteries are halfway 
toasted I’m still getting useful life out of them.

 

 

From: AF  On Behalf Of Steve Jones
Sent: Monday, August 14, 2023 9:57 PM
To: AnimalFarm Microwave Users Group 
Subject: [AFMUG] battery nerd question

 

Just trying to cipher runtimes

I have on hand 150ah 12 volt batteries, so thats what id be looking to use.

Excluding the conversion loss of a 12v to 48v step up converter is the math 
correct here?

12v 150ah=1800 watt hours
1800 watt hours at 48v = 37.5ah
50 watts of radio running 48v = 1.04 amps
37.5ah @ 1.04 amps = 32.77 hours runtime

 

does a step up that claims 95% efficiency mean 95% of the watt hours?




-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

Re: [AFMUG] battery nerd question

[Josh Luthman]

Four 150ah batteries would be a lot more coin than 12v to 48v if you can
afford the run time loss.

On Tue, Aug 15, 2023 at 9:53 AM Brian Webster 
wrote:

> How many of the batteries do you have? Do you need any voltages other than
> the 48 volts? If you have 4 batteries and only need 48 volts then wire them
> in series and not have to deal with the converter.
>
>
>
> Thank you,
>
> Brian Webster
>
>
>
>
>
> *From:* AF [mailto:af-boun...@af.afmug.com] *On Behalf Of *
> dmmoff...@gmail.com
> *Sent:* Tuesday, August 15, 2023 6:59 AM
> *To:* 'AnimalFarm Microwave Users Group'
> *Subject:* Re: [AFMUG] battery nerd question
>
>
>
> *You’re around C/30 which should be on the high end *of capacity*.
>
> Lower load usually means a little extra capacity out of the battery.  I
> realized that sentence might have been ambiguous.
>
>
>
>
>
> *From:* dmmoff...@gmail.com 
> *Sent:* Tuesday, August 15, 2023 6:56 AM
> *To:* 'AnimalFarm Microwave Users Group' 
> *Subject:* RE: [AFMUG] battery nerd question
>
>
>
> You can do the whole thing in Watts.
>
>
>
> 12V * 150ah = 1800 Watt-hours
>
> 1800Wh / 50W = 36 hours
>
>
>
> If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50
> / 0.95).
>
> There’s usually an efficiency curve for the device based on load and
> temperature so it wouldn’t be 95% in all circumstances.  Your system should
> be drawing less than 5A off the battery, and if your multimeter has a 10A
> fuse like most do, then you could put the meter in line and actually
> measure the amperage before and after the converter.  Then you’d know for
> sure.
>
>
>
> And the battery’s total capacity will have a curve based on C-rate so
> there’s some variability there too.  Usually it lasts longer when you’re
> drawing lower amperage.  You’re around C/30 which should be on the high
> end.
>
>
>
> Age and maintenance of the battery affect runtime as well.  If I want 6
> hours of runtime then I plan Ah for 12 hours runtime. When my batteries are
> halfway toasted I’m still getting useful life out of them.
>
>
>
>
>
> *From:* AF  *On Behalf Of *Steve Jones
> *Sent:* Monday, August 14, 2023 9:57 PM
> *To:* AnimalFarm Microwave Users Group 
> *Subject:* [AFMUG] battery nerd question
>
>
>
> Just trying to cipher runtimes
>
> I have on hand 150ah 12 volt batteries, so thats what id be looking to use.
>
> Excluding the conversion loss of a 12v to 48v step up converter is the
> math correct here?
>
> 12v 150ah=1800 watt hours
> 1800 watt hours at 48v = 37.5ah
> 50 watts of radio running 48v = 1.04 amps
> 37.5ah @ 1.04 amps = 32.77 hours runtime
>
>
>
> does a step up that claims 95% efficiency mean 95% of the watt hours?
> --
> AF mailing list
> AF@af.afmug.com
> http://af.afmug.com/mailman/listinfo/af_af.afmug.com
>
-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

Re: [AFMUG] battery nerd question

[Steve Jones]

we have a dozen or so, but are looking at pole mount micropops (our own
poles). We are losing a grain elevator site because they decommissioned the
elevator and theres no real options for the customers in some of the areas.
Im just trying to get to something we can get solar power with enough
battery to last through overcast. So Im calculating per battery runtimes,
then will look at number of batteries we would need to survive vs paying
for a ROW meter vs losing the customers. Just have to get to the cost per
customer to retain them and the benefit gained per pole


On Tue, Aug 15, 2023 at 8:53 AM Brian Webster 
wrote:

> How many of the batteries do you have? Do you need any voltages other than
> the 48 volts? If you have 4 batteries and only need 48 volts then wire them
> in series and not have to deal with the converter.
>
>
>
> Thank you,
>
> Brian Webster
>
>
>
>
>
> *From:* AF [mailto:af-boun...@af.afmug.com] *On Behalf Of *
> dmmoff...@gmail.com
> *Sent:* Tuesday, August 15, 2023 6:59 AM
> *To:* 'AnimalFarm Microwave Users Group'
> *Subject:* Re: [AFMUG] battery nerd question
>
>
>
> *You’re around C/30 which should be on the high end *of capacity*.
>
> Lower load usually means a little extra capacity out of the battery.  I
> realized that sentence might have been ambiguous.
>
>
>
>
>
> *From:* dmmoff...@gmail.com 
> *Sent:* Tuesday, August 15, 2023 6:56 AM
> *To:* 'AnimalFarm Microwave Users Group' 
> *Subject:* RE: [AFMUG] battery nerd question
>
>
>
> You can do the whole thing in Watts.
>
>
>
> 12V * 150ah = 1800 Watt-hours
>
> 1800Wh / 50W = 36 hours
>
>
>
> If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50
> / 0.95).
>
> There’s usually an efficiency curve for the device based on load and
> temperature so it wouldn’t be 95% in all circumstances.  Your system should
> be drawing less than 5A off the battery, and if your multimeter has a 10A
> fuse like most do, then you could put the meter in line and actually
> measure the amperage before and after the converter.  Then you’d know for
> sure.
>
>
>
> And the battery’s total capacity will have a curve based on C-rate so
> there’s some variability there too.  Usually it lasts longer when you’re
> drawing lower amperage.  You’re around C/30 which should be on the high
> end.
>
>
>
> Age and maintenance of the battery affect runtime as well.  If I want 6
> hours of runtime then I plan Ah for 12 hours runtime. When my batteries are
> halfway toasted I’m still getting useful life out of them.
>
>
>
>
>
> *From:* AF  *On Behalf Of *Steve Jones
> *Sent:* Monday, August 14, 2023 9:57 PM
> *To:* AnimalFarm Microwave Users Group 
> *Subject:* [AFMUG] battery nerd question
>
>
>
> Just trying to cipher runtimes
>
> I have on hand 150ah 12 volt batteries, so thats what id be looking to use.
>
> Excluding the conversion loss of a 12v to 48v step up converter is the
> math correct here?
>
> 12v 150ah=1800 watt hours
> 1800 watt hours at 48v = 37.5ah
> 50 watts of radio running 48v = 1.04 amps
> 37.5ah @ 1.04 amps = 32.77 hours runtime
>
>
>
> does a step up that claims 95% efficiency mean 95% of the watt hours?
> --
> AF mailing list
> AF@af.afmug.com
> http://af.afmug.com/mailman/listinfo/af_af.afmug.com
>
-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

Re: [AFMUG] battery nerd question

[Brian Webster]

How many of the batteries do you have? Do you need any voltages other than the 
48 volts? If you have 4 batteries and only need 48 volts then wire them in 
series and not have to deal with the converter.

 

Thank you,

Brian Webster

 

 

From: AF [mailto:af-boun...@af.afmug.com] On Behalf Of dmmoff...@gmail.com
Sent: Tuesday, August 15, 2023 6:59 AM
To: 'AnimalFarm Microwave Users Group'
Subject: Re: [AFMUG] battery nerd question

 

*You’re around C/30 which should be on the high end of capacity.  

Lower load usually means a little extra capacity out of the battery.  I 
realized that sentence might have been ambiguous.

 

 

From: dmmoff...@gmail.com  
Sent: Tuesday, August 15, 2023 6:56 AM
To: 'AnimalFarm Microwave Users Group' 
Subject: RE: [AFMUG] battery nerd question

 

You can do the whole thing in Watts.

 

12V * 150ah = 1800 Watt-hours

1800Wh / 50W = 36 hours

 

If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
0.95).   

There’s usually an efficiency curve for the device based on load and 
temperature so it wouldn’t be 95% in all circumstances.  Your system should be 
drawing less than 5A off the battery, and if your multimeter has a 10A fuse 
like most do, then you could put the meter in line and actually measure the 
amperage before and after the converter.  Then you’d know for sure.

 

And the battery’s total capacity will have a curve based on C-rate so there’s 
some variability there too.  Usually it lasts longer when you’re drawing lower 
amperage.  You’re around C/30 which should be on the high end.  

 

Age and maintenance of the battery affect runtime as well.  If I want 6 hours 
of runtime then I plan Ah for 12 hours runtime. When my batteries are halfway 
toasted I’m still getting useful life out of them.

 

 

From: AF  On Behalf Of Steve Jones
Sent: Monday, August 14, 2023 9:57 PM
To: AnimalFarm Microwave Users Group 
Subject: [AFMUG] battery nerd question

 

Just trying to cipher runtimes

I have on hand 150ah 12 volt batteries, so thats what id be looking to use.

Excluding the conversion loss of a 12v to 48v step up converter is the math 
correct here?

12v 150ah=1800 watt hours
1800 watt hours at 48v = 37.5ah
50 watts of radio running 48v = 1.04 amps
37.5ah @ 1.04 amps = 32.77 hours runtime

 

does a step up that claims 95% efficiency mean 95% of the watt hours?

-- 
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AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

Re: [AFMUG] battery nerd question

[dmmoffett]

*You’re around C/30 which should be on the high end of capacity.  

Lower load usually means a little extra capacity out of the battery.  I 
realized that sentence might have been ambiguous.

 

 

From: dmmoff...@gmail.com  
Sent: Tuesday, August 15, 2023 6:56 AM
To: 'AnimalFarm Microwave Users Group' 
Subject: RE: [AFMUG] battery nerd question

 

You can do the whole thing in Watts.

 

12V * 150ah = 1800 Watt-hours

1800Wh / 50W = 36 hours

 

If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
0.95).   

There’s usually an efficiency curve for the device based on load and 
temperature so it wouldn’t be 95% in all circumstances.  Your system should be 
drawing less than 5A off the battery, and if your multimeter has a 10A fuse 
like most do, then you could put the meter in line and actually measure the 
amperage before and after the converter.  Then you’d know for sure.

 

And the battery’s total capacity will have a curve based on C-rate so there’s 
some variability there too.  Usually it lasts longer when you’re drawing lower 
amperage.  You’re around C/30 which should be on the high end.  

 

Age and maintenance of the battery affect runtime as well.  If I want 6 hours 
of runtime then I plan Ah for 12 hours runtime. When my batteries are halfway 
toasted I’m still getting useful life out of them.

 

 

From: AF mailto:af-boun...@af.afmug.com> > On Behalf 
Of Steve Jones
Sent: Monday, August 14, 2023 9:57 PM
To: AnimalFarm Microwave Users Group mailto:af@af.afmug.com> >
Subject: [AFMUG] battery nerd question

 

Just trying to cipher runtimes

I have on hand 150ah 12 volt batteries, so thats what id be looking to use.

Excluding the conversion loss of a 12v to 48v step up converter is the math 
correct here?

12v 150ah=1800 watt hours
1800 watt hours at 48v = 37.5ah
50 watts of radio running 48v = 1.04 amps
37.5ah @ 1.04 amps = 32.77 hours runtime

 

does a step up that claims 95% efficiency mean 95% of the watt hours?

-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

Re: [AFMUG] battery nerd question

[dmmoffett]

You can do the whole thing in Watts.

 

12V * 150ah = 1800 Watt-hours

1800Wh / 50W = 36 hours

 

If they’re telling me 95% efficiency, I’d assume 50W out needs 53W in (50 / 
0.95).   

There’s usually an efficiency curve for the device based on load and 
temperature so it wouldn’t be 95% in all circumstances.  Your system should be 
drawing less than 5A off the battery, and if your multimeter has a 10A fuse 
like most do, then you could put the meter in line and actually measure the 
amperage before and after the converter.  Then you’d know for sure.

 

And the battery’s total capacity will have a curve based on C-rate so there’s 
some variability there too.  Usually it lasts longer when you’re drawing lower 
amperage.  You’re around C/30 which should be on the high end.  

 

Age and maintenance of the battery affect runtime as well.  If I want 6 hours 
of runtime then I plan Ah for 12 hours runtime. When my batteries are halfway 
toasted I’m still getting useful life out of them.

 

 

From: AF  On Behalf Of Steve Jones
Sent: Monday, August 14, 2023 9:57 PM
To: AnimalFarm Microwave Users Group 
Subject: [AFMUG] battery nerd question

 

Just trying to cipher runtimes

I have on hand 150ah 12 volt batteries, so thats what id be looking to use.

Excluding the conversion loss of a 12v to 48v step up converter is the math 
correct here?

12v 150ah=1800 watt hours
1800 watt hours at 48v = 37.5ah
50 watts of radio running 48v = 1.04 amps
37.5ah @ 1.04 amps = 32.77 hours runtime

 

does a step up that claims 95% efficiency mean 95% of the watt hours?

-- 
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com