Schumacher Charger not charging?

[Ufatz]

Sounds goofy, but I think the charger I bought last year for the cabin is faulty. Had it on little car and batt totally dead. Played around with it for a bit and nothing. Touched red to black clamps together and nada, no spark,no excitement. How likely would it be that this thing itself is DEAD? They are a reputable outfit and we must own half a dozen of them in total.

[aanderud]

Can you test the voltage with a voltmeter? If you're not getting 12-14 volts off the end, then it's probably dead OR.... a fuse?

I'm not familiar with this particular brand but some chargers/inverters/converter type things have a fuse that you can replace. One of my inverters has one that looks like a standard automotive fuse ( think it's 20 or 30 amps ). One of my battery chargers has a cylinder-shaped fuse in-line on the red clamp's cable. May want to check into that.

[Macgyver55]

Chargers often need to sense a voltage before they will turn on. If you are connecting to a dead battery it will not come on at all.

You can fool them into charging a dead battery by hooking up a good battery in parallel with it to get it started then remove the good one after voltage comes up over 4 volts.

From the Schumacher HSOforum:

"An automatic charger is designed to power the transformer when you first plug it into a receptacle. The automatic charger needs to “see” at least 4 volts in the battery to power up the circuitry. This initializes the charge sequence. When a completely discharged battery, or one with less than 4 volts charge remaining, is attached to the charger, the charger never “sees” this battery and will not begin the charging cycle. It will also cancel out the Engine Start function. The yellow charging light will also not come on. The meter (where used) will remain in the default “100%” position.

NOTE: Batteries that remain lower than 4 volts state of charge are often defective or just worn out. It is always best (safer) to check the battery with a hydrometer or Schumacher tester before charging."

[aanderud]

Oh, that's a great point MacGuyver. I had a battery that was so dead once that I had to throw a second in parallel just to get it started.

Try using that charger to top off a known-good battery once.

[gunner55]

We have one(Schumacher) at the lake that will read that the battery is 100% charged when I know it isn't. We simply unplug it, reset it, then it will read 70-80% & work correctly. It does this quite often, it's as if the chip in the charger needs to reboot(?) or something. We've had it for a while but it wasn't a cheap one & seems to work OK when we use it this way.

[Ufatz]

Okay gang-thanks for the ideas and observations. The battery I'm trying to charge is reading 4-5 volts so it is really down. But there most assuredly IS something wacky with this charger, Model SE 70-MA. There is no reset button on it. Am generally a fan of Schummacher and will keep fooling with this thing to see what happens.

But, since I have little patience with stuff that doesn't work right, if it keeps annoying me it is headed for the landfill. LOL

[Whoaru99]

Oh, that's a great point MacGuyver. I had a battery that was so dead once that I had to throw a second in parallel just to get it started.

Try using that charger to top off a known-good battery once.

A charger with a manual setting for the win.