Classic 250 Charge Current

[tecnodave]

dgd,

Ok I did mess around in trying to parallel several Chinese Tracer MPPT controllers, it did not work!, they could not set a stable input, even with dropping resistors. I tied my oscilloscope across the drop resistors and when one would sweep the others would be affected. Instability resulted. Gave up on that approach and was using 3 Tracers on one battery bank with separate arrays until I could budget the Classic. Lessons learnt!  Classic paid for itself by being able to top the batteries without running the Onan on dinosaurs.

td

[dgd]

td,

I like experimentation and its good to read you tried parallel Tracers together.  My limited knowledge of these would lead to doubts that Tracer experiments would be a good yardstick for Classic behaviour (unless boB unwittingly wrote the mppt scanning code for the Tracers).
However, the principle may be valid that having more than one PV mppting device on one PV array just leads to confusion unless they can somehow co-operate (KID bully mode etc..)

If I had a large enough PV array and a couple of Classics I would certainly give it a go.

dgd

[tecnodave]

dgd,

I am always experimenting in one form or another. A whole lot of reading tells me that the kid does have PWM control of the load output. So when I get him back from babysitting I am going to try about 900 watts PV in and battery diverted PWM out to a 24 volt  600 watt water heater element. I was trying to do that with the Classic but you can't have PWM in and out at the same time. (WBjr in and opportunity out) but it seems that the kid does have that ability with its load port and aux port together.

td

[boB]

I am not surprised that 2 or more paralleled charge controllers would not play well together without some sort
of communications.  Either some separate comm cable or by power line carrier on the DC input or battery side.

[tecnodave]

I was not really expecting it to work but I tried. I had a rather long run and only one set of wires 500kcmil aluminum utility direct burial 8 kv. Wire I was using. I ended up with separate positives and common negatives on the 4 conductor 3 phase feeder cable, kinda overkill but it was free.

dgd,

I think boB would not design the tracer on his worst day. I have never seen any MPPT controller that sweeps as slow as the tracer. Even the Well See does better!  Looking at epSolar's lineup it is obvious that they are coping Morningstar. epSolar's EDPIPDB.com is a dead copy of the Morningstar SunSaver Duo , their remote readout is so close to the Morningstar they are maybe interchangeable? They look nearly identical.  and the eTracer is so similar in design, layout, and features you cannot help to think it is a clone of the TS- MPPT line, reading the manuals will have you convinced of this. Even the charts are copied!

Lesson learnt, cheep junk will do the basics but that is where you will stay until you find something that is user programmable.

td