Textron Total Charge Not Charging

[jaredb03]

I know there is about 50 post about these chargers not charging but since the one i inherited from the previous owner is modified they don't seem to really apply to mine.
It's a green front Textron Total Charge, and it's not charging. It comes on and hums but the ammeter does not move from 0. I had it charging my batteries that were at 35.6 volts for 10 hours and didn't charge them at all. I have checked the fuse and it is good, and continuity is good on all the wires i can check.
I attached some pictures to show what the guy did to it. It looks like for some reason he removed or permanently pinned down the reset switch, and he also told me that the auto shutoff doesn't work either. I would like to get this charger back working, and possibly get the auto shutoff working also if possible.

[jaredb03]

A wire was fried and that was why it wasn't charging i got that fixed but would still like to know what i would have to do to get this charger back to new function.

[jaredb03]

Also wondering with the state of my charger and not being able to auto shutoff how do i tell when the batteries are fully charged? I plugged it in about 4 hours ago and it started around 25 amps on the ammeter now it is at about 11-12. batteries where at 35.6 volts when i plugged it in and the batteries are under a year old according to the previous owner. Thanks

[JohnnieB]

Technically, the cells on a battery are not fully charged until the Specific Gravity of the electrolyte ceases to increase while a charging current is passing through the cell, however open circuit terminal voltage tracks Specific Gravity fairly well, so it may be used.

Trojan recommends their batteries be charged until the on-charge voltage is in the 2.45VPC to 2.79VPC (Volts per Cell) range, or from 7.35V to 8.37V for a 6V battery, or 44.10V to 50.22V for a 36Vbattery pack. Most automatic 36V chargers shut of when the pack's on-charge voltage climbs into the 44V to 46V range, so let them charge until the on-charge voltage reaches about 45V.

Considering the batteries were at 35.6V, about 35% SoC (State of Charge) it will take many hours to reach and on-charge voltage of 45V, and having been discharged that low, they might not recover.

After the charge is terminated, let the batteries rest for about 12 hours (neither charge nor discharge) and measure pack voltage and individual battery voltages.
The at-rest voltage for the pack should be 38.2V, the individual batteries should be 6.37V and all six should be within 0.1V of each other.
Attached is an at-rest voltage vs State of Charge chart.

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To get your charger shutting off automatically, you will most likely have to replace the control board. That is the usual reason for by-passing the relay and turning it into a manual charger.

To check if the control board is bad, trace the black wire from the fuse shown in your third picture, to the timer.
That wire should attach to the spade lug on the black box the yellow wire is plugged into.

Once that is done, plug charger output cable into cart without plugging charger into AC power.

You should hear the relay click.
If so, plug charger into AC power and transformer should hum and Ammeter deflect to over 15A.

If not, you probably need a new control board.

[jaredb03]

Originally Posted by JohnnieB

To check if the control board is bad, trace the black wire from the fuse shown in your third picture, to the timer.
That wire should attach to the spade lug on the black box the yellow wire is plugged into.

Once that is done, plug charger output cable into cart without plugging charger into AC power.

You should hear the relay click.
If so, plug charger into AC power and transformer should hum and Ammeter deflect to over 15A.

If not, you probably need a new control board.

Ok did this and I heard the click so I hooked up ac and turned it on and it jumped to 19 amps. So apparently the board is ok? I didn't leave it on very long cause the reset button isn't there and I don't know what it does. Is it safe to run it with the board hooked up and the reset switch like it is? Also what is the part number for a new switch? Thanks in advance.

[JohnnieB]

Great news. It works.

The reset button is a 50A circuit breaker. Later models use a Part# 19362-G1 and it looks like it would fit.
You can probably get it for LE$$ at your local electrical supply, they are off-the-shelf items.

Also, a 50A fuse in a panel mounted fuseholder would also work.

In most carts, the white wire from the charge receptacle is attached to the battery pack's main positive terminal with a 50A or 60A fuse, so the circuit breaker in the charger is somewhat redundant.

Let us know what the batteries and battery pack come up to after the are charged.

[jaredb03]

well what they have on there is a 50A auto reset circut breaker so i think that should be fine right? Im confused at why they would bypass the auto shutoff if everything is functional. I guess i will plug it in and see what happens. Rough idea how long should it take to charge from the 35% im at just so i have some idea when the auto shutoff should shut it off.

Edit. Also i saw on a post something about supercharging your battery pack. What does that mean and how do i do that. I think it was Gonkulor that had posted it but cant find that same post now.

[JohnnieB]

It will take roughly 8 hours to get them up to 80% SoC and another 8 hours to go from 80% to 100 SoC, but the charger will time out before that happens (12 hour safety shut-off)

If it times out, just unplug the charger from the battery pack and then start a new charge cycle.

If the batteries have been setting in a partially discharged state for very long, they probably are bad.

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I'm not sure what "Supercharging" the battery pack means.
There is something called an equalization charge, which is basically charging the batteries to a higher on-charge than the usually are to smooth out the difference in the at-rest voltages between the batteries in the pack.

Bypassing the relay in an older style golf cart charger (like the one you have) is one way of doing that.