Similar story here. The fan started going on one of mine, I replaced it then the whole thing fried anyway about 2 months later. Seems most of the 20 year old high frequency chargers are just at the end of their service life. Once in a while you find a low cycle count one, but those are getting fewer and farther between.
And there are no drop-in replacement options so that makes it really tough even for those who can turn a screw driver or a wrench for direct replacement situationsā¦
Maybe thereās a market for taking an angle grinder to everything on the Zivan PBC but the battery and lock-out connectors and the AC input then wire in something thatās a little smaller and will fit inside the plastic cover of the Zivan.
Actually the Quick Charge Corp SCO-7210 will just squeeze in and bolt up where the zivan was with no modification to other components aside from the wire end connectors and you lose the tri color pod led. Not a good charger for lithium, but a stellar old school iron core transformer for anything that has lead or gel in it
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wow it literally looks like an iron core xformer but with a little display and control panel on one side.
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Yup. Weighs 26 freaking pounds too. Itās a brute force charger with a few options. What it does, it does very, very well. Failures are almost unheard of. Iāve heard of only one failing; it was a guy on here about a year ago, a fluke occurrence and Quick Charge sent him out a new charger.
They have a lifepo4 option that has to be turned on at the factory, somewhere on here there is a thread (I think, might have been PMs - I donāt recall) where Dave and I were looking at the profile curves and I think Dave said it could be used for lithium, but only a certain size pack and a BMS to cut the charge was critical IIRC.
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Iām off to camp today where the GEM is.
Going to unplug the Zivan power cord and plug a computer cord directly into an outlet to see if it powers up.
Also, as far as using the NOCO charger. I know that I can only charge 1 battery at a time. In order to do so, do I have to fully disconnect the battery that Iām charging or is it okay to leave all the batteries connected?
Turn off the main switch under the seat and you can leave them connected.
You donāt need to disconnect anything.
Sometimes it is good to at least switch off the Main Battery Disconnect.
Bring along a meter and get a read on each battery before and after. Hopefully they did not get too low in your absence.
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I would shut it off. 00-04 suffer from a parasitic drain in the electronics.
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So tested all the batteries individually. 12.2 - 12.6 before the 1/2 hour ride.
After the 1/2 hour ride still about the same, except for one of the batteries. It was reading 10.3
Charged up all the batteries again using the NOCO 10am charger.
Tested individually. Same results. All were over 12v before the ride except the same one as before it was at 10 again.
Any idea what might be going on?
How do you test the pack voltage?
How about load testing the Gem, whatās the process for that?
Keep in mind, only have a multimeter 
Tip- Go through all your batteries with your NOCO and note their V. Then do another charge cycle on them again. They should be more up closer to 12.80 to 13.00 before you take off on a run.
What you just did would be considered a runtime or capacity test.
That battery dropping to 10.3 has failed and has no capacity. Any time your batteries go below 50% State of Charge (SoC) it does a little bit of damage internally. Do it often enough and it will totally kill it. A wet cell LA battery ~12.00v is @50% SoC and considered depleted.
If you want to do a load test you can fasten your meter to the top of a battery and watch what it does when under load. You can do this while driving around or do it as a brake stand test in the driveway. Do each battery and note how far each one dips when you give it a good mash on the throttle. Your weak battery will also show up in this test.
Best place for a full pack reading is on the B+ (POS) and B- (NEG) connections on the motor controller when key is ON.
that is a depleted battery! stop. And if that is what the battery reads after you fully charge it thatās a dead battery.
Read up on what 12V Pb batteries are and the voltages you should see fully charged(steady state), trickle charged(right after charging) and at 50% capacityā¦
Why is the NOCO showing the battery at full charge then? Just trying to understand how this all works.
The batteries are brand new. Bought them at Batteries Plus.
Maybe Iām not using the multimeter right? I set it to 200V DC and put the red on the + and the black on the - and then read the meter.
What should the batteries read on the meter at full charge? If they are 12v, I donāt understand why they would ready 13v, wouldnāt that be overcharged?
It sounds like you are using the multi meter correctly. It does look like you have 1 defective battery. Since these are all in series, that one battery will drag the entire system down
a 12V lead acid battery is made up of 6 cells internally and when in good working order each cell will store ~2.1V so a fully charged battery will show 12.6V. Deep cycle batteries have more lead and often you will see them fully charged holding 12.8V.
So if your battery charger says that that 12V battery is fully charged but itās only holding 12.2V that means something is wrong. If the charger works well with other batteries then it must be the battery itself. Maybe that battery was not properly fully charged like all the other batteries so when you drove it around it had only 50% charge while the others were at 100%. But the time the others are at 50% that weak battery is at 0% and damage is being done to the chemistry of the battery.
To recharge a battery there has to be more voltage put across its terminals than it finishes with in order to ādriveā current through the battery for recharging. So often times there will be ~14.0 V put on the battery while it is charging. To hold that charge, once fully charged, a 13.8V trickle charge is left on the battery and it just dribbles current through the battery to make sure all the chemicals and lead stay where they are supposed to be. That charge will even hold there for a while after the 13.8V is removed and this is why we often ask people to read the battery voltage 1 hour after the charging has completed. After 1 hour, the steady-state charge on the battery can be measured and gives a rough estimate of the batteries State-of-Charge(SoC). 12.6V or more will indicate itās likely a healthy battery. Anything below that means that battery is weaker.
Since the GEM puts six batteries in series(each connected to the other in a string) it is VERY important that all batteries have similar characteristics( charge, health, etc ). A dead or weak battery in the string is bad news for performance and could also lead to other batteries failing. The battery charger( 72V ) really puts about 84V( 14V * 6 ) but if one battery is sick it might only get 10V or 12V across its terminals and that means the other 4V gets put onto the other batteries( 4v/5=.8V) so the other batteries are charged at 14.8V and thatās getting on the high side of whatās needed to charge the batteries and can start heating up the batteries helping to harm their health.
Thereās tons of this information on the Internet if you google and read up on Lead acid battery charging.
What dougl said ^^^
I set it to 200V DC
But also try switching your meter to the 20v scale when checking 12v batteries. It may not be as accurate on thelow end of the 200v scale.
In your charging/testing scenario above you stated that you charged up all the batteries with your NOCO and checked them again. One battery was at 10 again.
Is it possible you just missed it in your charge loop? Maybe put the wrong clamps on the wrong posts? (Itās easy to do). I find it suspicious that it did not come up at all. Maybe your charger faulted and took the day off?
So the possible bad battery came back up to 12.2 volts, but after the ride for 2 minutes at which point the display said -15.
Checked all the batteries and only that battery had gone back to 10v. The others didnāt seem to move down.
Thatās why Iām trying to rule out a bad battery. So I can return it.
Why not just pull it out and take back to batteries plus. Theyāll throw it on a tester and probably replace it under warranty.
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spinning your wheels hereā¦ if that battery has not charged to more than 12.2V then it is bad and as @Erniea15 stated you should take it back and have them give you a replacement. You do not want a bad battery in your string of batteries.
Too many low batteries that are supposedly newā¦
Bad batteries being sold as new?
Meter accurate?
Charger worth a crap?
PEBTKAC?