# Zilla - no power under 135V?



## remy_martian (Feb 4, 2019)

What's the voltage at the instant of these floorings of the pedal?


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## Jb24601 (Aug 29, 2019)

1-2V pedal to the metal. Pretty much the same at 144V as at 136V. 
Amp draw 50-150A. Not noticing any sudden high amp draw or sudden voltage drop on throttle changes, just a real lack of power under 135V. At 135V with 170Ah showing, I can go pedal to metal and get only the barest response. 
I’m fortunate to have another Zilla on the bench so I can do a swap.


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## kennybobby (Aug 10, 2012)

What does the LBV1 setting at 131 mean?

There is bound to be some setting to cut back the torque/current by a certain amount when approaching or reaching some setting of a low voltage limit. my guess it's a hairball setting.


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## remy_martian (Feb 4, 2019)

https://evwest.com/support/zilla%20manual%202.02d.pdf



I asked for the voltage reading when floored, never got an answer. Sounds like the transients are dipping below 124V. Easy to fix...set LBV to 10 and grab a bag of popcorn.


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## kennybobby (Aug 10, 2012)

What cells are you using for your pack and What is their configuration?


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## Jb24601 (Aug 29, 2019)

Six Tesla S modules in series, 135V nominal.
Upon further drive testing, it occurred to me this is behaving like a weak battery pack; takes a charge, runs good for a while then voltage drops and amps fall off. The Zilla Lv is good for a broad range of voltages, so it should perform whether the volts are 110 or 140, but if the batteries are weak then that might be a more plausible explanation.
(Later edit): It’s the pack. Orion 2 reported a weak cell in each of three modules (tesla), there are six total. They’re wired serially, so weak links drag everything down. Sorry for mis-categorization of this post, it’s not Zilla related.


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## reiderM (Dec 30, 2020)

Jb24601 said:


> Six Tesla S modules in series, 135V nominal.
> Upon further drive testing, it occurred to me this is behaving like a weak battery pack; takes a charge, runs good for a while then voltage drops and amps fall off. The Zilla Lv is good for a broad range of voltages, so it should perform whether the volts are 110 or 140, but if the batteries are weak then that might be a more plausible explanation.
> (Later edit): It’s the pack. Orion 2 reported a weak cell in each of three modules (tesla), there are six total. They’re wired serially, so weak links drag everything down. Sorry for mis-categorization of this post, it’s not Zilla related.


Any visible damage to cells, eg. severed cell fuses? Having one faulty cell group is rare, three is almost unheard of unless your modules were damaged in shipping etc.


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## remy_martian (Feb 4, 2019)

Did you try setting LBV to 10?


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## Jb24601 (Aug 29, 2019)

ReiderM, there is no apparent damage to the modules or the fuse wires, but ya never know. More detailed testing forthcoming. My supplier agrees this is unusual. It’s probably some kind of user goof-up, or just really bad luck.


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## remy_martian (Feb 4, 2019)

Did you try setting LBV to 10?


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## Jb24601 (Aug 29, 2019)

LBV to 10? Do you mean Low Battery Voltage, the point at which the the Zilla controller would diminish or cut off voltage to the motor? 10 Volts? You’re one of the sharpest here, perhaps you could reason this out for me. LBV cutoff is the only setting I know of that that would limit power in this build. It’s currently set to 125V, and I’m seeing issues at 135V.


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## remy_martian (Feb 4, 2019)

As it approaches LBV it backs off the power. 135 is close to 125. Any sag you can't see on a meter, but the controller does, will trip a backoff.

It's a test...don't leave it there to drain the pack to 10V, but charged up to do a test run will tell you if you need to, and likely do, need to tune that value to 100V or whatever. 

For troubleshooting, get it totally out of the way at 10V. Do a run. If the problem goes away, then finesse LBv. Finessing from the start won't necessarily reveal the problem, which is why you do the run with it ridiculously low.


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## dtbaker (Jan 5, 2008)

It is quite likely that under full throttle your cells sag more than you might expect.... I set my LVindicator to -25% of nominal which doesn't flag 'expected sag', but does catch a near empty pack before you ruin the pack.

if your nominal voltage is 135v, then you might expect 25% voltage drop under full load = 100v. But, if you see 100v at rest at a stop light, you are dangerously low and want the controller to put you in turtle mode.


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