Bill, Thanks for the tip. Do you have an automated measurement system for the 10v inter-comparisons or do you manually log them with a spreadsheet?
I don't think the 12v are better, but it is interesting that some people have modified them to dual batteries. I do not think there is any added benefit unless someone happens to use a lot of those particular 12v batteries. So far I have two with the 6v packs and one with the 12v. I have a fourth one waiting to be repaired once I finish my current projects. Todd Sent from my iPad > On Aug 24, 2014, at 17:44, "Bill Gold" <wpgold3...@att.net <javascript:;>> wrote: > > Todd: > > I check the batteries every month per the 732A manual. Usually I keep a > few used cells from previous packs around that seem to be ok after checking > them for capacity just like checking the battery pack. I can usually spot > cells going bad with that method. If I don't have a spare set then I just > substitute a used cell until I receive a new set. > > I agree with you that the cheap ones are crap. I have used Power Sonic > a lot with some a few EaglePicher and one set of Enersys. The EaglePicher > are crap so I will never use them. EaglePicher have had a couple out of 8 > that have failed very early. I have never tried Panasonic. So I stick with > the Power Sonic's. I am not sure why the 12 volt ones would be better than > the 6 volts because 12 volt is just 6 lead acid cells while the 6volt are 3 > lead acid cells. If one of the 6 cells in the 12 volt battery go bad then > the whole battery has to be changed. So you better buy good quality 12 volt > batteries. > > I just can't seem to source batteries locally easily at a reasonable > price. So I order them from Allied usually. > > Bill > > ----- Original Message ----- > From: "Todd Micallef" <tmical...@gmail.com <javascript:;>> > To: "Discussion of precise voltage measurement" <volt-nuts@febo.com <javascript:;>> > Sent: Sunday, August 24, 2014 8:13 AM > Subject: Re: [volt-nuts] 732A and Prologix received > > >> Bill, >> >> I use a lot of the 12v 7ah batteries for my UPS backups and 732B. But yes, >> I was mistaken. The 12V 5ah batteries are the ones that I am using in one >> of my 732A. There is more play inside the tray with the 12v batteries by >> several mm as compared to the 6v which only has a 2-3mm. The 12v > conversion >> is not difficult, but it is easier if the battery tray has already been >> machined for the 12v batteries. The battery tabs don't line up well with >> the existing holes and need to be widened. Two additional holes must also >> be added. >> >> Sourcing the batteries locally is more of a convenience than waiting for >> the delivery. The el-cheapo 6v batteries are a waste of money and I have 8 >> batteries so far to prove it. They died the first time I had a 6hr outage >> and would not hold a charge after that. >> >> Todd >> >> >> >> >>> On Sat, Aug 23, 2014 at 1:21 PM, Bill Gold <wpgold3...@att.net <javascript:;>> wrote: >>> >>> Randy: >>> >>> I get 6 volt 4 amp/hr (or 4.5 amp/hr) batteries and they will fit >>> perfect. Power Sonic PS-640, Genesis NP4-6, Panasonic LC-R064R5C and >>> others >>> that are in this size and package. Order from one of the usual > electronics >>> distributors like Allied, Mouser, Digikey. This is a very common > battery >>> as >>> it is used in a lot of "EXIT" signs so they are lighted when the power > goes >>> out. I don't see how the 12V 7AH will fit as they are too large. I > guess >>> you could use a 12V 5AH (PS1250) as it is the same size as 2 x 6 volt 4 > AH >>> but the terminals are in the wrong place so you will have to "nibble" > out >>> the aluminum plate that holds them in the 732A battery pack. You have > to >>> be >>> careful if you use the 12v 5AH as you will have 4 extra battery > connection >>> leads to deal with and connect correctly. I would stick with the 6V > 4AH. >>> New batteries will last around 12 to 14 hours before the "CAL" light > goes >>> out when AC power is not applied. So shipping to Cal Lab can be a > problem >>> if it is a distance away, or you have to use a shipper like UPS or FEDEX >>> and >>> you ship the night before and then use their "Morning delivery" and the > Cal >>> Lab is expecting your 732A. Same on the way back to you. Of course you >>> could always strap another battery on the 732A and hook it up to the > "ext >>> power" plug to last longer. I have seen it done. The issue is to get > the >>> Cal Lab to charge the extra battery before they ship the 732A back to > you. >>> >>> When you remove and work on the battery pack always have the AC > power >>> plugged in. The "CAL" led will stay on because the 18.6 v regulated > supply >>> is working. >>> >>> The "CAL" light is to indicate that power has not been lost to the >>> Reference Amp or other associated circuits. When the raw supply > (battery) >>> voltage drops below about 21 volts the "CAL" light will go out. Below > that >>> voltage the heater circuits will not work correctly and the 18.6 volt >>> regulated supply will not regulate. The requirement is that the > Reference >>> Amp be kept "alive" at all times to maintain the output voltage that was >>> measured at the time of the most recent Calibration or Certification. > When >>> the semiconductor junctions are unbiased and cool off when power is > lost, >>> and then power is restored the result will be a different 10 volts than >>> before the power failure. My experience is that after all of the years >>> that >>> these units have been powered up, this won't happen and when power is > lost >>> and then restored, even months later, the 732A will come back to almost >>> exactly the same 10 volts as when they lost power, usually with in 0.2 > PPM >>> after 24 hours of "warm up". >>> >>> What type of hookup leads are you using when measuring the 1 volt >>> output? What is the PLC set to? I always use 100 PLC to measure this. > If >>> you don't have "low thermal" connection leads you can experience uV > changes >>> for a minute or more after plugging in the leads due to the "thermals" >>> generated because of the difference in temperature between the banana > jacks >>> on the 732A and the banana plugs of the leads. I have found that even > just >>> plugging in the lead will generate a thermal difference because of >>> difference of temps and some heating due to the physical act of just >>> inserting the plug because of friction between the jack and plug (my > theory >>> at any rate). You have to allow at least a minute or more before being >>> able >>> to make a measurement after plugging in the leads. I just measured the >>> variation of the 1 volt output of my 732A and using my 3458A and I got a >>> total difference of 0.159 uV over 40 measurements using 100 PLC on the > 1 >>> volt range of the 3458A. Using the MATH function and all of the data > you >>> can collect. That was after waiting for several minutes after plugging > in >>> the leads. >>> >>> I hope all of this helps. >>> >>> Bill >>> >>> >>> >>> ----- Original Message ----- >>> From: "Randy Evans" <randyevans2...@gmail.com <javascript:;>> >>> To: "Discussion of precise voltage measurement" <volt-nuts@febo.com <javascript:;>> >>> Sent: Friday, August 22, 2014 9:03 PM >>> Subject: Re: [volt-nuts] 732A and Prologix received >>> >>> >>>> Todd, >>>> >>>> Thanks for the info. I have several Panasonic 12V 7 AH batteries that > I >>>> keep topped off and they have very low current draw (~2 to 3 mA at > 13.5 >>>> VDC) when charged and at their float voltage, so I am pretty sure they >>> are >>>> in good condition. I will look at getting those in the units after I >>>> ascertain the condition of the 732. >>>> >>>> So now I have a what appears to be a functioning 3458A and a 732A but >>> they >>>> slightly disagree. I am like the man with two watches that disagree > on >>> the >>>> time - which is correct? For the moment, i am only concerned with >>>> stability. The need for absolute accuracy will come later. >>>> >>>> Randy >>>> >>>> >>>>> On Fri, Aug 22, 2014 at 8:06 PM, Todd Micallef <tmical...@gmail.com <javascript:;>> >>>> wrote: >>>> >>>>> Randy, >>>>> >>>>> You have two possible choices. It can be configured with 4 x 6v 4Ah >>>>> batteries or 2 x 12v 7Ah batteries. Hopefully the previous owner has >>>>> modified the battery pack already. A couple of mine needed a nibbler >>> tool >>>>> to remove enough of the aluminum cover that fits over the tops of > the >>>>> batteries. The original cover will short out to the battery tabs >>> regardless >>>>> of the battery configuration if this is not done. >>>>> >>>>> You can find larger capacity batteries that will give you slightly > more >>>>> battery life. I lost a couple sets of mail-order batteries after a > few >>>>> extended outages. I would recommend going with locally bought > batteries >>>>> instead of the cheaper mail order. My local Batteries Plus will >>> typically >>>>> have some warranty if I remember correctly. Moving forward I will > only >>> use >>>>> 2 12v batteries and pre-charge them on a battery charger to equalize >>> them >>>>> before putting them in the 732A. I think the cheap batteries did not >>>>> discharge equally, and would not recover when power was applied. >>>>> >>>>> Inspect the back plane for damaged traces and look at the > capacitors. I >>> had >>>>> a few that looked questionable. So far, I have replaced all the big >>> caps >>> on >>>>> the pre-regulator and regulator boards. My feeling is that once > these >>> go >>>>> online, they should run as long as possible between repairs. >>>>> >>>>> The battery charger circuit may need adjusting. I tweaked mine and > it >>>>> seemed to work fine. >>>>> >>>>> Todd >>>>> >>>>> >>>>> On Fri, Aug 22, 2014 at 10:42 PM, Randy Evans < >>> randyevans2...@gmail.com <javascript:;>> >>>>> wrote: >>>>> >>>>>> I received my Fluke 732A today. Just powered it up but it needs > new >>>>>> batteries. Any suggestions for sources (I haven't opened up the > unit >>>>> yet - >>>>>> I want to make sure it works before doing that). Also received > the >>>>>> ProLogix USB-GPIB adapter. I plan on using Mark Sims' CAL ran > data >>>>> dumper >>>>>> program to get the CAL data from my 3458A. Should be a busy > weekend. >>>>>> >>>>>> Randy >>>>>> _______________________________________________ >>>>>> volt-nuts mailing list -- volt-nuts@febo.com <javascript:;> >>>>>> To unsubscribe, go to >>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >>>>>> and follow the instructions there. >>>>> _______________________________________________ >>>>> volt-nuts mailing list -- volt-nuts@febo.com <javascript:;> >>>>> To unsubscribe, go to >>>>> https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >>>>> and follow the instructions there. >>>> _______________________________________________ >>>> volt-nuts mailing list -- volt-nuts@febo.com <javascript:;> >>>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >>>> and follow the instructions there. >>> >>> _______________________________________________ >>> volt-nuts mailing list -- volt-nuts@febo.com <javascript:;> >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >>> and follow the instructions there. >> _______________________________________________ >> volt-nuts mailing list -- volt-nuts@febo.com <javascript:;> >> To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >> and follow the instructions there. > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com <javascript:;> > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. _______________________________________________ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.