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larrymcg
12-06-2005, 12:03 AM
I've been using the Hobbico Accu-Cycle Pro Series Elite charger for a year charging two 2-cell Kokam 1500mAh Li-Pos at the same time. This charger is built to do two at a time. I would charge at 1C (1.5A) and it worked exactly as it is supposed to.

Now I've got two 3-cell 1800mAh Li-Pos. The charger has 10 programmable memories so I programmed up one for the 3-cell batteries. I set it up for 1.5A (being cautious with new batteries). What I've noticed is that if I am charging one battery the current quickly goes up to 1.5A like its supposed to but as soon as I start the second battery the current starts to drop. With two batteries the current levels off at 1.3A on each battery and then starts dropping slightly as the battery voltage approaches 12V. At 12V the current had dropped to 1.2A on each battery. It stayed there until 12.6V was reached and then the current continued to drop as it is supposed to.

I'm powering the charger from a wall plug (this charger can be plugged in or connected to a 12V supply for field use).

Seems to me the charger should be able to handle 1.5A (or even 1.8A) when charging two batteries. The charger is not getting hot - just barely warm.

Does anyone have any experience with this charger and want to comment on its seeming inability to charge two 3-cell Li-Pos at 1.5A??
Maybe it's defective but OK for 2-cell batteries?

Larry

trogdor
12-06-2005, 05:09 AM
If you are using the supplied power supply, its just that its limit is about what you are seeing. If you upgrade to a better power supply, it'll charge both outputs at 2 amps with 3 cell lipos on each. I never used the supplied PS and just use a 12amp Pyramid power supply I got for around 40 bucks and can run the elite, a triton and a Worly all at the same time on 3s packs at full capacity.

Matt Kirsch
12-06-2005, 01:02 PM
Exactly. The power supply is maxxed out, and the charger is seeing this as a drop in voltage. When it sees a drop in voltage, the charger reduces the charge rate automatically. It has to, otherwise it can't maintain a high enough voltage to continue charging the batteries.

NotAnAceYet
12-07-2005, 05:39 AM
I have the same charger. The specs are max 2 amps charging rate - combined - both outputs - on AC power supply. Can charge at a higher rate on pure DC.

larrymcg
12-07-2005, 06:19 AM
Seems that you are all right. I just found a review of the unit and it says that using the supplied power supply the charger can deliver, to each output when both are used, a max of 2A with 2-cell lipos and 1.35A with 3-cell lipos. With a power supply capable of 5A at 12VDC you can get 2A with 3-cell lipos. I don't think the user manual explains this, or at least I haven't found it.

Thanks for the help,
Larry:)