Battery charger problem

[blazemaster83]

I have an old solar 550 high amp charger that my employer was throwing out because it has no output. I took it home, got it on my bench and did a little testing. It does put out dc voltage, and the switches/gauges all seem to work. The problem is it doesn't put out any amperage. With a low battery connected, i get 1 amp of draw through an amp clamp on the dc cables. I took the rectifier plate out and all the diodes did not look burnt out, they looked just fine.

Electrical stuff is not my forte, im more of a machinist/mechanic. Am I testing correctly? Do I need a new rectifier plate? This thing is pretty simple so i cant imagine theres much to go wrong.

I did some searching and cant find much on low amp output

 

[Chuckster in NJ]

Try leaving it connected to the battery for 15 minutes and see how it behaves.

 

[dogdog]

Battery draws what ever it draws. Might not be an indicator. As long as it outputs a stable voltage of 13.2 to 15.3 v no less and no more. Otherwise you might need one of those load test things.

 

[justsam]

I would measure the DC output voltage with and without a load. If it sags below 13 or so volts, there is an issue. Also switch your meter to read ACV here as well, as this can give an indication of proper rectification. Backing up from there you can take a look at the AC voltage coming out of the step down transformer. I would expect it to be around 20 VAC. Be careful of using these older "brute force" chargers as they can boil the electrolyte out of a battery if left connected too long.