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landyacht318's avatar
landyacht318
Explorer
Nov 30, 2013

Modified my Schumacher

Model number sc2500a. No longer in production.

This Charger works pretty nicely as a converter, on the 12 amp setting, handling such cycling loads as a ~2.7 amp compressor fridge and a 6.2 amp mattress heating pad, without getting confused and shutting off as it does on the 2 amp or 25 amp setting.

I've had a difficult time clicking on the "place order" button on an Iota or PD or Powermax converter, because this charger meets my needs, and with the 3 different charging profiles(regular, deep cycle, and AGM/GEL), it might be considered superior in some circles.

However I would not trust if for a GEl battery, and there seems to be little difference between regular and deep cycle, that I have noticed anyway.

MOst recently, and not shown in the picture is that I got rid of the SAE 12v quick connector which loved to heat up, and replaced it with 30 amp Anderson powerpoles, which do not.

What is shown in the picture is the External Fan I installed in place of the annoyingly loud fan that came inside the unit.


The 40mmx10mm fan which came installed in it was rated at 28db, and 6.3 CFM and 0.12a. Much too loud for my ears.

The 60x20MM Fan I installed draws the same current, but moves 3x as much air, and I can barely hear it.

BUT, I think perhaps it is too much airflow. There is no battery temp sensor, I figure there is some sort of temp sensor inside the unit, and now that it has 3x the air flowing through it, it suspects it is in a freezing environment and is raising the charging voltages accordingly.

The voltages which rarely went up into the 15's, now have done so at the end of every charge cycle, and I must now babysit the dang thing, and unplug it, as my batteries are new, and do not need such voltages at this stage in their life.

The new fan came with 2 optional inline resistor cables to lower the fan speeds and noise levels. The slowest one will still move more air than the original fan. I can hook both resistor cables inline to slow it even further but am not sure of the airflow with both in series.

I am not very confident in my fan/temp sensor hypothesis. The fan runs the same speed on the 2/12/25 amp settings, and the charger only seems to produce any noticeable heat on the 25 amp setting. It has also done the sky high voltages before(not for years) with out flashing the light that says it has decided to do the equalization cycle where one might expect to see such voltages. The EQ feature is Not manual

I guess I am gong to install those resistor cables now and see if the charging voltages change, but I suspect they wont, and I will have to babysit it near the end of the charge cycle from here on out, which I'd rather not have to do.

What do you all think about my hypothesis?

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