Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Richard230]

I know that only a few 2012 Zero owners have experienced the two-step startup glitch, where sometimes it takes two boots to get the throttle to function when the bike is first used in the morning after charging all night. It really isn't much of an issue for me, since it only happens once a day when I first leave my home.

However, I think I have found a way to prevent the problem.  If I unplug the charger the previous afternoon and let the bike sit without charging for the night, it seems to start up the first time the next morning.  I have tried this for the past week and so far it seems to be working.  Previously, about 75% of the time, the bike would require that you turn on the ignition switch twice in order to get moving.

[frodus]

What controller are you using?

And can you measure the voltage of the pack while it's fully charged?



I think I know what the problem is.....

[Richard230]

I believe the 2012 Zero S uses a Sevcon Gen 4, size 4 controller.  When I visited the factory in December I asked them about my problem and they told me that it was a random glitch that had something to do with re-programming the controller to resolve the issue of the original glitch that was the subject of the recall last fall.  I was told that the problem occurred in about 4% of the bikes that had their firmware upgraded, like mine.

I could measure the pack voltage if I knew where to access the terminals with my voltmeter.  But I wouldn't want to take anything apart as the bike is running fine and I don't like to mess with things when everything is working well.  My record of reassembling things that I have taken apart is not a perfect one.

[BSDThw]

You can easily measure the voltage if you unplug the plastic cover at the top right on the battery pack where the quick charger is connected.

frodus what is it you think will make this happen?

[Richard230]

Thanks for the tip, BSDThw.  That was so easy that even I could do it.   

With the charger plugged in and the bike fully charged after a short ride to the grocery store this morning, the voltage is 74.4 volts.

[frodus]

I'm thinking it might be a voltage setting on the controller. There's a max voltage and if the controller sees a voltage too high, it disables. Cycle power and it's fine.

By Letting the batteries settle overnight, the voltage settles and you'd be under that max. Also, if you leave the headlights on for a minute or so after a full charge, it should depleat that surface charge.

It's just a hunch, but it sounds like what the Curtis does when you supply too much voltage..... it protects itself and shuts down.


I just don't know what the nominal voltage is for that pack or controller.

[Richard230]

I couldn't find the nominal voltage of the battery pack listed in my owners manual, but I am pretty sure that I recall someone (probably Protomech) posting that the pack is 66 volts, nominal and uses EIG cells.

I just pulled the charger plug and after 10 minutes I checked the voltage again and it is still at 74.4 volts.  I plan to leave the bike off the charger and check it again tomorrow morning to see if it changed any overnight.

[Richard230]

So I took some more voltage readings this morning and determined nothing of interest - other than you can't trust voltmeters.

I had been taking my voltage readings with my 30-year old digital $20 Circuitmate DM78 (because it was handy and is very easy to use).  Last afternoon it read 74.4V for the pack and this morning it read 74.3V.

I then tried my $110, 5-year old Extech MA220 meter and it read the pack as having 75.7 volts.  Turning the ignition on and off and back on again and off again, the voltage never changed from 75.7 on this meter.  I then plugged in the charger and it immediately started charging at 972 watts and I read the voltage as 75.1 volts.  After the charger cut off the voltage reading with this meter was 74.9.

With the bike charging, my Circuitmate meter read 74.7 volts.  After the charger cut off, it read 74.5 volts.

So this was probably just a waste of time, other than to tell me that different multimeters are probably no more consistent than different air pressure gauges.

As near as I can tell, none of this means anything other than I can't depend upon my two voltmeters to give accurate and consistent readings.     But I am thinking that the old $20 meter is probably more reliable than the $110 meter.   

[BSDThw]

The "powertrains-sales-sheets.pdf" says Maximum Voltage 74.7V; Nominal 65.7V!

Frodus: The Sevcon settings I can see is

Battery over voltage protection Address "2C01h"
"Over voltage start cutback = 101V"
"Over voltage limit = 103V"

Richards 74.4V should not be a problem.

[frodus]

Thanks for comfirming. It sounded like maybe an OV protection thing, but it shouldn't be with only ~75V.

[Richard230]

The start-up glitch is back.  Letting my bike sit off the charger overnight didn't help yesterday and it even failed to start on the first time after sitting in a field for 6 hours.  So I guess I will be living with the occasional two-step start-up routine for sometime.

[NoiseBoy]

A good quality multimeter is a sound investment, especially for an EV owner.  Im a fan of Fluke meters and picked up a just-above-entry-level model 175 iirc for about £100 second hand on ebay with a calibration certificate so I know its trustworthy.  It also settles quickly and will measure frequency on AC etc. etc.  You might not get the fancy features of the cheaper singing and dancing chinese models but they are much nicer to use.

[WindRider]

Fluke meters work very well and if you use a meter often and the measurements are important, they are worth the investment.

[firepower]

measurer your PC USB 5V for quick test  , use the meter that give most accurate reading of 5V , at least it show which of your two meters is best.