So I suspected our battery charger is not charging, would put it on a battery and it didn't seem to help. I hooked up out DVOM and got nothing on DC voltage, nothing on DC amps, so I guess it doesn't work anymore? Is this a valid test? Is there some sort of "fuse" or "circuit breaker" internally that can be replaced or reset, is there anyway to fix these things? thanks-
I would connect the charger to a battery, leave it turned off, and connect the voltmeter to the battery also, with it set to DC Volts. See what the voltage is. Then turn on the charger, and see if the voltage increases. If it does not, then the charger is probably not working.
Depends on the charger.... I had a Schumaker that would not charge a completely dead battery, you had to "excite" it with jumpers from another battery to get it to output voltage. It wouldn't light up a light bulb! But that was the way it was made. When it cratered, I made sure the new one would output voltage all the time because I need 12v at times to check circuits.
yes, there can be fuses and circuit breakers. I check both alternators and chargers by measuring battery voltage with nothing connected then connect charger and see if voltage goes up if it goes up charger is working. if the charger doesn't move when it is connected, disconnect everything and take the cover off and look for fuse or breaker
hooked it up to a DEAD battery (12.1 volts), turned the charger on and nothing, still 12.1 volts...will open it up and see if there is a fuse or breaker...
Internet search engines are so helpful. The 85-2250 NAPA charger is built by Shumacher. From the users manual: http://www.manualslib.com/manual/149446/Schumacher-00-99-000207.html?page=12#manual 9.6 OVERLOAD PROTECTION The charger uses an output circuit breaker and a thermal breaker to prevent overheating and damage to the charger and the vehicle. If after repeated starting attempts, the charger does not indicate any output on its meter, it may be because one of the two breakers has opened. If the output breaker opens due to excessive current, a popping noise will be heard. It will automatically reset itself in a couple of minutes. If the thermal breaker opens, it will automatically reset itself in about 5 to 30 minutes. And here's your parts list if you need new components. http://www.centurytool.net/85_2250_NAPA_Battery_Charger_Parts_List_s/275.htm
Also check the selector switch; the one on mine started to come apart and lost connection (it snapped together). I super-glued it back together, no issues since....
Battery charger is a transformer with a rectifier to change AC to DC and a few gauges and controls. Not very complicated if you know a little about electricity and electronics. I have fixed them before, one thing you can do is put in a diode bridge if the old rectifier is burned out but if you do so, be careful, you will get a LOT more output. You will want to cut to half wave rectification to be safe.
My quit a while back...opened it up and found one wire was disconnected off the transformer...simple fix....i suppose rolling around on the hard wheels these take a pretty good beating...
While on the battery chargers. On my charger it has a reconditioning mode. I took a battery from 2010 that's been setting on the concretein the shop for at least three years. Just to see what would happen after a day on reconditioning mode it's been in my 99 suburban for a month now working great couldn't believe it brought it back to life.
Timely thread. I've got two different bench top chargers that are recently suspect. An old 6/2 Schaur, and a not so old, fancy digital Schumacher. Gonna get out the DVM & do some checkin'.
Turns out that was the problem with ours too, learned quite a bit about the chargers due to the problem though...
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