Someone gave me a panel - can I build on it?

oldnslow

Observer
That controller is designed to charge a battery. It needs a battery on its output to do anything. Its not like a power supply that puts out voltage whether there is a load or not. If you hook up a fully charged battery you won't see much. Try putting a load on the battery, like a brake light or turn signal bulb. You should see at least 2A out of the controller with that load.

A word of warning: Some charge controllers will be destroyed if they have power on the panel connections but no battery connected. I destroyed a 4.5A SunGuard unit that way at work a few years back. No smoke, no flames, just dead. I hope for your sake the SS-10 does not have that issue.

Since you are going through a metal roof with your wiring a fuse at the panels would be a good idea, but not necessary. They are limited to about 6.5-7A short circuit current and even 16AWG wire can handle that without melting. You should be using at least 12AWG there. You could fuse them at 10A. AFAIK the panels can put out short circuit current all day with no damage.
 

dwh

Tail-End Charlie
Voltmeter across the terminals will always show whatever voltage the battery is at. So if the battery is at 13v, then that's what you'll see everywhere. [EDIT: NOT true with an MPPT controller.] As the battery voltage rises over time, you'll see that higher voltage everywhere you put the meter across the +/- terminals. The battery limits the voltage of the whole system.

Ammeter has to be in series to measure amp flow. As in, disconnect the solar + from the charge controller, connect the lead from the solar to one probe on the meter, and stick the other probe in the charge controller +. Make the power flow THOUGH the meter. Be careful - my multimeter is limited to 10a when used as an ammeter. Anything over that will pop an internal fuse. Also have to move the probe to a different hole in the meter to measure amps with it.

Do it on the SOLAR side of the charge controller. I believe all Morningstar charge controllers specify hooking up the battery first. Because that's where they get their power to operate.
 
Last edited:

dwh

Tail-End Charlie
I doubt this will make a big difference right? I imagine I'll get better results from the angled install when I park into the sun and worse results when I don't.

More like you'll get results when you park in the sun, and no results when you don't.
 

Forum statistics

Threads
185,527
Messages
2,875,534
Members
224,922
Latest member
Randy Towles
Top