Need advice on APT Upgrade please.

[shaniac]

Greetings, I have an APT Power Center that has a 35Amp breaker between my solar array and my external charge controller. My charge controller is rated at 50Amps. (Blue Sky Solar Boost 50) We are off grid.

My problem is that when I run a heavy load, like my dish washer, and then my water pressure pump kicks in simultaneously, the 35 Amp breaker "sometimes" trips. Then my dishwasher is using 100% power from my batteries and it pulls them down faster than you can read this post. If the breaker does not trip, then my dishes are clean 45 min later and I get to stay married. : ) I think the breaker trips because my charge controller is passing 49.5 Amps in full sun, and I think the breaker just decides to surrender after a while as it should.

My APT PC is rated to 35 Amps (or at least that is whet the built in charge controller is rated for, that I am not using.) From reading this thread at outback...

http://www.outbackpower.com/forum/viewtopic.php?f=9&t=2141

... I believe I can swap out the 35AMP breaker between my array and the charge controller with a 50 AMP breaker and my problem will be solved.??

Do you agree with this conclusion? Or am I missing some key data here?

Here is a shot of the APT.

http://stevenshane.com/solar/apt.jpg

Mine is identical except it is rated for 35Amps.

I can not call the manufacturer because APT has left the building, and besides I trust you guys before anyone else. This forum is invaluable!!

As always, thanks for your help and let me know if you need any more data.

- Steve

Moved to the proper section.

[wiredwrong]

OK, I gotta ask?/ "will your wires handle more than 35A?, breakers are rated to protect wires, if the wire cant handle the load than don't put in a bigger breaker!"  Its cheaper to replace a fuse/flip a breaker,. than a burnt down house...

[shaniac]

Well yes, thank you this is true, but the APTs come in different flavors for different power types. For example the one in the thread I linked to above had a charge controller in it that went higher than mine, thus if anyone who is familiar with one of these might be able to tell me if I can place a 50 AMP breaker in there and the rest of the wiring will hold. (sans the on board charge controller that I am not using.)

Anyone have any knowledge on these APT boxes?

Thanks again.

[DanG]

If it is intermittent perhaps looking at the wiring distribution and increasing conductor AWG in the feeds or decreasing the run lengths, and going through branch circuits and soldering wire-nut connections to gain back the one, two or three percent voltage drops in a 'xx' foot run. If you have any voltage drop the circuit will draw more amperage to make up for it - 120V for 1680 watts = 14 amps vs. 115V for 1680 watts is 14.6 amps.

Too small AWG would be especially important for the water pump since the inrush at start up is nearly a short circuit, too small of wiring makes the time period required for starting stretch out long enough that the preset breaker reaction delay is forced to trip.

You may surprise yourself and find a weak link that will solve the random breaker flip.