Thank you for the reference, I have bookmarked the site. It referenced SLA batteries, this scooter has AGM batteries.

For all practical purposes, they are one and the same...

 

If your charger won't work unless there is a battery connected, here is one possible way to test it.

View attachment 90964

Can you help me follow that suggestion please? Some suggestions as to a dummy load and a replacement for the batteries, which fall under the diagrams '24V power source I think.
Thanks

 

The on-board ammeter has a black wire and red wire connection on the rear of it. These two wires lead back into a wire harness that comes from the charger output. Would unplugging these two connections and connecting each to the respective color leads of a portable test Ampmeter be a possible method of testing the charger (and also the on-board ammeter)? I would essentially be replacing the on-board ammeter with another 'Ammeter' in my suggestion here.

 

Some suggestions as to a dummy load

See post #11.

 

Can you help me follow that suggestion please? Some suggestions as to a dummy load and a replacement for the batteries, which fall under the diagrams '24V power source I think.
Thanks

For the load, you can pick up a couple 12v break lights at any auto supply store. Connect them in series to get 24V operations. For the 24V source, you can use the existing batteries. If they show ~12 = 12.5 volts, they will be sufficient. They don't need to supply much current, as that will be supplied by the charger. You can use a variable resistor connected as a rheostat to 'tweak' the voltage down to kick the charger into bulk charge. Otherwise, you can use any 24V DC source, including wall-warts, bench power supplies, batteries or a 24V transformer/rectifier (just use the rheostat to turn down the voltage because it will be considerably more than 24v)

There is a chance you won't need to do any of this. Some chargers require a battery (or voltage source) be connected, some don't. I have had only one that requires it.

 

Is the ammeter analog or digital? If it's digital, it could be a voltmeter measuring the drop across a sense resistor.
The simplest way is to put a 1 ohm 30W resistor across the charger. You can calculate current by measuring the voltage drop across the resistor. The charger output should be in the neighborhood of 28V.

If you don't have appropriate power resistors, you could make an electronic load using a voltage regulator like an LM317 (heatsinked) drawing 1A and let the regulator dissipate most of the power. I'll post a schematic when I get to a computer with a schematic editor...

dl324: I have a Rascal 600F and have verified all voltages are correct. After cleaning all connectors, (Brand new Batteries (2)), the scooter now goes about 1 mile from the original 1/2 mile when I got it used from a Vet Friend. The amp meter was not working, until I cleaned the contacts, now working just fine. The charger appears to be operating correctly. When I use the unit until it is very slow, the meter indicates 0 amps. When plugged in the meter indicates 4 amps. After charging for about 45 minutes the amp meter indicates 0 amps, the charger shuts off and the unit operates great, except for the duration of operation issue. . I can only arrive at the issue may be 1) the drive motor is drawing a lot of current, or the charger is crowbarring. Not sure at this point. Any help is greatly appreciated.

 

The replacement batteries were UB12350 at http://www.monsterscooterparts.com/mobility/mobility-brands/rascal/rascal600t/rascalbattery.html. Those are 12V 35Amps @ the 20 hour rate.

For testing in a pinch, you can wire an 1157 tail light bulb energizing both filaments for a total of 35.3 watts. The break light is 27 watts and the running lights is 8.3 watts. The batteries should draw down slowly for over 20 hours. If the batteries were fully charged, it could drop from 12.6 to 12.0 pretty quickly, but then slowly down to 10.75 volts which is fully depleted. But I'm sure you read that at battery university.

SLA and AGM are the same as far as maintenance.

Fully charge the batteries from a standard car charger on slow charge.