Battery (really solar panel) Disconnect Question

Does anyone make a charge controller that has a cutoff feature built into it?

Good luck with it. Either way.:C

Had a C40 controller destroyed when one of my 14 yr old batteries went south, so yes it is advisable to disconnect the panels fist, thats the way I was tought when I worked in the solar for 3 yrs. in Arizona and was working for 1 of the best @ Imperial Dam. and all I had was a 80 watt panel charging while the rig was in storage at the time. Just my thought's.

The only caveats in the ZS-30A controller manual concern not shorting the connections during installation. They do suggest covering the panels to turn them off during the install. Since it was factory installed, I assume they didn't short anything and had the panels somehow disabled (probably didn't plug them into the roof top combiner), as it all seems to work.
"
- Given sufficient light solar panels always generate energy even when they are disconnected.
- Accidental ‘shorting’ of the terminals or wiring can result in sparks causing personal injury or a fire hazard. We recommend that you cover up the panel(s) with some sort of soft cloth so you can block all incoming light during the installation. This will ensure that no damage is caused to the Solar Panel or Battery if the wires are accidentally short circuited.
- Always install a battery fuse on each circuit including the solar controller
- Do not reverse connect the wires to the solar panel or battery
"

They also suggest adding a 40A fuse on the + wire runs, both in and out from the controller. Since I can't see them, I have to assume they were added at the factory. God help me if they ever pop.

The Morningstar manual says it is an NEC requirement to have disconnects on the array and also on the battery side. It seems more like a safety issue with the high panel voltages. They also say the controller can be damaged.

There is also the need with 12/24 controllers to first connect the battery to let the controller learn what system voltage is before connecting the array.

I have had my controllers on array but not battery at times with no issues, but maybe just lucky.

BFL13 wrote:

Powertour wrote:
Yeah the charge controller I inherited with this setup is a Chinese LMS unit.

I don't see anything in the sparse (key word) documentation that says to avoid having panels wired to the controller unit if you don't have a battery bank wired up/connected at the same time.

From the LMS manual:

Caution: For secure installation, must follow below connect sequence: First battery, second load, and the last photovoltaic panel.
…………………………………………………………………

Appreciate you pointing that out.... the only manual I'd found online didn't reference that.

Powertour wrote:
Yeah the charge controller I inherited with this setup is a Chinese LMS unit.

I don't see anything in the sparse (key word) documentation that says to avoid having panels wired to the controller unit if you don't have a battery bank wired up/connected at the same time.

From the LMS manual:

Caution: For secure installation, must follow below connect sequence: First battery, second load, and the last photovoltaic panel.
…………………………………………………………………

Yeah the charge controller I inherited with this setup is a Chinese LMS unit.

I don't see anything in the sparse (key word) documentation that says to avoid having panels wired to the controller unit if you don't have a battery bank wired up/connected at the same time.

I just replaced my dying factory FLA batteries with 2 X 100Ah LiFePO4 units. To do this, I had to disconnect the batteries while the controller was up and running and it was a sunny day. I actually considered pulling the 3 rooftop panel connectors out of the 3 way combiner, but after consulting Winnebago Tech Support, they said no need.
My system is a factory installed Zamp Solar setup, 3 X 100W panels and the ZS-30A PWM controller. When all was reconnected, everything is up and running with no apparent ill effects. So, I'm going to *assume* this charge controller doesn't care if you disconnect the batteries, either at the battery terminals manually, or with an added disconnect switch. Which I didn't add. Never ocurred to me to add one.
Just in case you've got the same, or similar, setup.

You will likely ruin the charge controller. I have not seen a controller that does not warm to not have a battery hooked up before connecting the solar panel.

That said, I have accidentally hooked up the panel with no battery with no damage to the controller. I do not know what the issue is or what can go wrong, but imagine without a battery there that the voltage levels can spike too high. The battery is able to absorb any stray voltages or odd voltages into its storage capacity rather than all that spike go into the electronics.

You will have to either put the switch between the panel and the controller, or not put any switches in.

Another option is to put cardboard or plywood over the panel (give it a few mins to depower) and then it should be safe to disconnect, or do this at night when there is no sun to power the panel. Don't let the cover blow off though.

I have a truck camper with the batteries on the truck, not the camper. When I would remove the camper then there were no batteries, so I put in a small exit sign battery that I could switch over to that the panel had a battery still connected, this was a post-controller switch.
Since then I have replaced the little battery with a regular marine battery, but still use the switch for the panel that is not usually connected to that camper battery.