Solar Switch

[GaryS1953]

Hi All - When I installed my solar setup I put an in-line fuse between the panels and the charge controller, but unfortunately, it's on the roof. Never occurred to me I might want an easy way to shut off the amps to the charge controller. Now I'm realizing I will/do need to do maintenance on my battery bank, meaning I will need to disconnect them. Renogy says NOT to have solar power coming into the CC with no batteries connected, so I need a switch to turn them off and on. What do all of you use? I have 2 165 watt 12 volt panels in series connected to a Renogy Tracer 40 AMP MPPT CC. I have found plenty of switches to use on the battery side of the CC, and I have one there, but what is appropriate for the panel side?

Thanks!

[CA_Traveler]

My 750W solar is 100V @ 8A and I use a HD A/C disconnect switch to disconnect both positive and negative wires. The inside wires have split loom and are located behind cabinet panels. The basement wires are visible and have split loom to the switch and CC. No fuse on the solar wires as one is not needed. The battery side is a 80A surface mount CB.

The basement wires are labeled including instructions for switch sequence usage and the switch sequence label is also in the battery compartment.

Yes I know the A/C switch is not DC rated but for my use and application I would expect it to last a very long time. But available everywhere for $15.

[2oldman]

GaryS1953 wrote:
Ok, you guys have given me a lot of great ideas, and I appreciate it. One more question, whatever switch I use, should it be on the negative line or the positive line, or does it matter?

My opinion is it doesn't matter.

[Bobbo]

GaryS1953 wrote:
Ok, you guys have given me a lot of great ideas, and I appreciate it. One more question, whatever switch I use, should it be on the negative line or the positive line, or does it matter?

If you get a Double Pole switch, both lines are switched. Double Pole Single Throw means it is a simple ON/OFF switch that disconnects 2 lines.

[pianotuna]

Hi Gary,

Best switch would be single throw double pole. I.E. both positive and negative disconnected.

If using a single pole single throw, put it on the positive side.

[GaryS1953]

Ok, you guys have given me a lot of great ideas, and I appreciate it. One more question, whatever switch I use, should it be on the negative line or the positive line, or does it matter?

[jake2250]

2oldman wrote:
Who needs to settle down? Go argue with someone else.

So hey Bro, in the hierarchy of solar,,,,, You 2oldman would be far versed on answering the original question. Instead, you pick a lower value and trash them. Yet give nothing of value to the thread?
So I ask,, 12v,24v,36v-------100v. how do we select a simple ON/OFF switch? Do I select my current voltage? or go to the next level? Or two levels above that?
Did you build your system or did you wright a check?
Cause I have not found anything of use from your posts!
from my research,, Any simple switch at or above the rated voltage and amperage should be sufficient. What ever,, sorry to the OP for wasting your time!

[Fubeca]

You need to have a switch to handle the amperage.

But many of us also want to limit the voltage drop. I have 4ga wire from my combiner box to my controller. I also have an appropriately large switch.

[2oldman]

Who needs to settle down? Go argue with someone else.

[jake2250]

Jeeze 2oldman settle down!

Ok, my mistake, 24 volts, puts him in a little different bracket.
In other responses it was referd to the OP as running 18-20 Amps thru those panels, but I am not sure if that is in series?
So when I referd to the 8 amps more, I meant 8 amps more than my 10 amps (comparing OP to My self 10+8 being 18).

A large Battery cut off switch as apposed to a properly rated rocker switch is what I am referring to as a Large switch!

Yeah I can see the need for a robust Switch/ cutout as yours, But OP is not running 800 watts at 100 volts! Either am I. As you stated he's probably only gonna get 250 watts@24V, A step up is always better but he asked for what is appropriate for his set up?

So I am sorry if ME with a small 200 watt system throwing in my 2cents on an appropriate SWITCH from panel to CC didn't meet your specs, But we are not in your league!
Maybe re read his question? HE already has an In line fuse set up, all he needs is a simple switch before CC!
So what is appropriate? You haven't thrown that out there, just pissin in the sand! At least I said my solar guy told me double the amps and your good! SO is something 24 V 20 Amps in a switch appropriate for him or not? Or should a Nuclear Fusion device be better!!

In reality, OP could go to HOME DEPOT and buy a 110V 15amp home rocker switch as long as it is indoors and that will work!

[2oldman]

jake2250 wrote:
And the OP has 130 Watts more and 8 amps more. yeah, I can see going with a 185 amp disconnect.


So even if the OP decides to Double his panel size, he is still under 40 amps and still at 12v. Why such a large switch/disconnect? Wouldn't you size it for the intended job?

Ok, first let's get the facts straight.

He doesn't have 8 amps more, his panels are in series. Nobody recommended a 185amp disconnect. He's not at 12v.

Which large switch are you talking about?

In my particular case, I run 100+ volts, which can arc when switched. I presented what I use, period. I didn't mean the OP must use that big of a switch, I presented it as a choice, not because it's the "correct" size, but because it's a robust, solid, well-built mountable switch that will work when he decides to enlarge his array. Pianotuna also mentioned that. Right-sizing is nice, and minimum, but going a bit more means you can upsize your systems without having to replace everything in them. And, if a switch is used often enough, you want the darn thing to actually be able to switch 100s of times without breaking. So it's not just the electrical rating that counts.

Besides, he asked what we use.

[time2roll]

Any 10+ amp toggle switch is fine. I would get two pole, single throw.

[jake2250]

2oldman wrote:

jake2250 wrote:
why are some of you going with such big switches? I feel mine is over kill at 30 amps?

Some of us have more panels at more voltage. And we want switches that don't wear out.

And the OP has 130 Watts more and 8 amps more. yeah, I can see going with a 185 amp disconnect.
have had my install for almost four years now,, Picked up the trailer Thursday and installed batteries,switched on the solar. That darn teeny tiny switch worked! Guess in hind sight I should have installed a 36V 250 amp service cut out with that line of thinking!
I do agree that my little switch probably isnt man enough for my system, But at what ratio should I have followed? Everything I looked at in a switch I found with the one I installed, IE: wire size,maximum amperage draw,Interior/exterior,ease of installation etc.
So even if the OP decides to Double his panel size, he is still under 40 amps and still at 12v. Why such a large switch/disconnect? Wouldn't you size it for the intended job?

When I called my solar supplier and asked him for advise, he told me to go to an auto store and pick up a 12v switch and try to get at least something with double the amperage. So in theory, for me a 20 amp 12v switch would work. OP would be looking at like a 40 amp switch??
Or Am I not seeing the big picture here?

[2oldman]

jake2250 wrote:
why are some of you going with such big switches? I feel mine is over kill at 30 amps?

Some of us have more panels at more voltage. And we want switches that don't wear out.

[jake2250]

I have 200 Watts, 12v panels. I use one of these as my panels produce 10 amps max!
I remove batteries when in storage so I need to shut the panels off before controller.
Question: why are some of you going with such big switches? I feel mine is over kill at 30 amps?

[pianotuna]

Hi,

I'd get one rated for high amperage so that it will not need to be replaced if and when the solar system is upgraded for more wattage.