[solspirit]

An issue that I'm trying to figure out...

I have a Manzanita PFC-20 that I'm attempting to use for various applications (charging TS Cells, AGMs, Gels). Recently, I tried it with a 36V nominal Gel battery set-up with a voltmeter and ammeter connected up to monitor the battery side. I turn the voltage trim adjustment until the yellow limits led turns on. Then I turn the voltage trim adjustment until the yellow light turns off.
So far so good.
I then turn the amps knob clockwise (from the "off" position) and almost immediately the yellow limits led turns on (and the blue timer led starts flashing).
I repeat aforementioned steps numerous times with me turning the voltage trims adjustment every higher with each step and observing the same behavior.

All this while, I never see the voltage on the battery pack go up and I never see any Amps pumped into the battery pack.

Could my control board (or the trim pot connection) be broken?
Has anyone else seen similar behavior?

-Sol

 

[Frank]

I'd call Manzanita Micro about it...

 

[EVfun]

I'd contact Manzanita about it but I'm pretty sure I know the problem (because I experienced those symptoms.) It sounds like the internal fuse for the charger output has blown. There is a rush of current that flows from the battery being charged back into the charger when it is first connected to a pack. If you, like me, keep swapping the charger from pack to pack it is possible over time that the fuse will get a bit grumpy about the repeated surges and blow one time when you connect your charger to a pack.

Good thing this happened at a reasonably low voltage setting. If you are set to near max voltage it can damage the charger, as it's just like powering it on without a load. It is best to always turn the charger on with the current know turned down to further minimize this risk. Sounds like the charger is fine since you are still getting proper light behavior for the expected problem. My fuse blew plugging into a 128 volt pack and the charger was set for 146 volts and I tried several times before realizing the problem. My charger was not hurt. Do not replace the fuse with one that lacks a proper DC voltage rating. Manzanita can advise and supply the fuse.

 

[solspirit]

Thank you both for your help.
It was indeed the fuse.
I ordered a couple of LittelFuse L50S 30A from Manzanita directly.
I would suggest going to them directly about it. The price is reasonable and shipping was good.
The charger seems to be working now.

In other news, there is a new faceplate/control board that they are now making available with preset voltages (up to three) in addition to allowing the voltage to be adjusted manually. Such a feature could be useful.

So overall, when something is not working, check power connectors, wire connectivity, fuses, and look for toasted parts on the PCB.

Sol