# Question on the programming for controller setup.



## major (Apr 4, 2008)

There is nothing standard about this. Most every motor controller (family) handles "programming" differently. In most cases, programming is, in fact, the act of setting certain parameters. Many of the controller manufacturers have the manual available on-line, and if not, try requesting a copy from them. If they won't supply a prospective customer the manual, I wouldn't purchase their product


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## dougingraham (Jul 26, 2011)

I only know the Evnetics Soliton controllers first hand. On those you can select the motor voltage, motor current, and max power in KW. The max power is good to set to something sane if you have enough pack voltage to get to the upper limits of the voltage range. It will cause the current to taper back as the motor voltage goes up. For example you could set the voltage to 172, the current to 1000 and the kw to 150 to prevent the possibility of an event. You also can hook up a tach sensor and select a max RPM.

On the battery side you can select max amps and two different low end voltages. One is the voltage where it will not run at all if the voltage is below that set point. The other voltage is where it will still run but at that voltage the current is tapered back in a somewhat linear fashion between the two voltage settings. I have my low voltage cutoff point at 1.73 volts per cell and the taper back voltage set to 2.7 volts per cell.

I would guess the Zilla has similar settings.


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## timk225 (Sep 19, 2014)

What type of cells are you using to have a 2.7 volt and 1.73 volt cutoff? Not Lithium-Ion, I think. Lithium-Ion isn't supposed to be allowed to go below 3.0 volts per cell.

Thanks for the answers, I am glad to hear they can get into some real details for power control.


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## dougingraham (Jul 26, 2011)

timk225 said:


> What type of cells are you using to have a 2.7 volt and 1.73 volt cutoff? Not Lithium-Ion, I think. Lithium-Ion isn't supposed to be allowed to go below 3.0 volts per cell.
> 
> Thanks for the answers, I am glad to hear they can get into some real details for power control.


I am using LiFePO4. You can take them to whatever you want under load. If the resting voltage is below 2.35 for any length of time you will have a problem. I set those limits because I drive the car when it is cold out and the batteries are cold. When the batteries are cold they sag horribly. On a normal warm day you can never get them to go that low under the 6C battery current limit I have configured in the Soliton. I used to have the bottom cutoff set to half nominal (1.6 volts per cell) but when I started using my DC-DC converter I realized that it probably would have a problem if the battery sagged below 90 volts. The 2.7 volts is the bottom balance point and if the resting voltage is ever that low the pack is exhausted anyway. Setting the limits this way lets me drive the car when it is near zero degrees F. I don't know how cold the batteries can be and still reasonably drive the car. Ive driven it down to around 10 degrees F.


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