From: Lee Hart <[email protected]>
> I thought I would ask again for any explanation on how the 0-5k pot
> works on the zilla to increase voltage (counter-intuitive)
> and how does the BMS affect that by reducing voltage?
I just installed a orion BMS for a guy with a wv buss before leaving
Florida and wrote a post on it but some how got deleted .
The buss customer was in a hurry for me to get done and just wanted ("
do what ever is quickest") a light on the back engine compartment (
not even a light on the dash or a buzzer :-( ) . I don't remember
which 2 wires I used to control the relay but they should be in the
instructions . I like Lee's way of putting the 2.5k resistor in
parallel as it won't stop the car dead but cut back on the power in a
way that you will notice it .
<The standard arrangement for EV
controllers that use a 0-5k pot box is:
- Minimum resistance = minimum speed.
- Maximum resistance = maximum speed.
- Shorted pot wires forces the controller OFF.
Actually, any resistance under a few hundred ohms is off.
- Open pot wires also forces the controller OFF.
Actually, any resistance over about 4500 ohms forces it off.>
This set up gives a lot of safety for thing that can easily happen
<You need to talk to someone very familiar with the design of the
controller (like Otmar Ebenhoech for the Zilla) to get an accurate
answer on this.>
I would save your one call to the "controller god" for a real problem
. This is more a question for your dealer who makes money on selling
the parts . When I was setting up the Orion BMS I did have to call
them and they where very helpful ( probably not had to tell 100's of
people which end of the soldering iron to hold ) . There are a lot of
feathers on this , Audrey with her 900 number voice talked them into
letting us become a dealer so If you don't know which two wires run
the relay when the voltage of any cell drops below it thresh hold I'll
have her look it up .
>But, it's not really necessary that you know. It's only necessary that
you set up your Orion BMS to change the *resistance* across the potbox
terminals to limit the motor speed.>
Yes but Mike is probably worried about hooking something up wrong ,You
can do Lee's set up and just power the relay with a 12v source and see
that it works , then hook the BMS to the relay coil. ,
>Did you say the Orion BMS has a relay that it turns on if any cell's
voltage is low?<
I think you can program the BMS to either turn on or off for the
fault ( like a dp relay and you pick what state you want)
>You can set it to cut
back on the throttle, or even prevent you from driving if the total pack
voltage falls under X volts. This is another way to keep from destroying
cells if one goes dead.<
Yes but I wouldn't count on this to much as one cell going bad and
dropping voltage will not be enough "tell " the controller there is a
problem .
I will be coping your relay idea and sending it on if that's ok .
--
--
Steve Clunn
Merging the best of the past with
the best of the future.
www.Greenshedconversions.com
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