Help disconnecting solar panels with MPPT Controller and no quick disconnects.

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JohnO

Veteran Member
Joined
Nov 13, 2020
Messages
77
Vessel Name
Tsula
Vessel Make
Kadey-Krogen 42
Sorry if this is answered somewhere else on TF ... did some research and didn't find exactly what I needed.

I'm needing to disconnect my house batteries. I have 2 PV panels installed with a 30A MPPT Controller and Remote Panel. From what I've read, it looks like others have installed quick disconnects on either side of the MPPT Controller. However, the PO installed the solar system and it does not look like there is any quick disconnect between the PV panels and the controller ... just the socket connections close to the PV panels.

So, assuming no quick disconnect, what's the best way to disconnect the PV system / panels and controller ... disconnecting the plugs at the panels or disconnecting the wires at the controller? I know I need to cover the panels so they are not putting out power, but not sure of the appropriate place to disconnect and in what order.

My current plan / order of disconnection would be:

1. Cover the PV panels
2. Disconnect the PV panels from the controller (not sure where the right place is to disconnect at the controller or exterior at the inline connections by the panels?)
3. Disconnect the batteries.

Reconnection would be in reverse order.

Any guidance would be much appreciated!
 
Either place that is convenient. Disconnected at the inline connections the ends are shielded from shorting due to their design, but it makes no difference to the panels or controller. You can cover the panels or wait until after sunset.
 
You know what you're doing. The shading doesn't matter unless you get sloppy with the disconnect...

But always panels first, battery next. The controller can't deal with panel input unless powered first.

Same when you re-power, battery first, panels next.
 
You know what you're doing. The shading doesn't matter unless you get sloppy with the disconnect...

But always panels first, battery next. The controller can't deal with panel input unless powered first.

Same when you re-power, battery first, panels next.

Shading matters if you unplug the MC4 connectors. They're not meant to be connected or disconnected under load.
 
Thanks for bringing up that question.
I had NO idea where the solar panel breaker is located.
On the American Tug 34/36, the majority of breakers are in the tank/battery room on the fwd bulkhead, most on the on the port side. And that ladies and gentlemen is were the solar panel breaker is located. The one exception is the breaker for anchor windless. It is mounted in the stateroom, stbd side of the berth base, outside. I still have to sort out the location of the stern thruster breaker and put my hand on it. It's in the tank/battery room.

Of course, this makes no sense to those who do not own an AT34/36.
 
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Shading matters if you unplug the MC4 connectors. They're not meant to be connected or disconnected under load.

I can see this. I meant the screw terminals right on the controller.
 
But always panels first, battery next. The controller can't deal with panel input unless powered first.
Depends on the controller. Most can, if they couldn't and you trip a breaker on the battery side you toast the controller.
On the American Tug 34/36, the majority of breakers are in the tank/battery room on the fwd bulkhead, most on the on the port side.
On the AT34, there are breakers and fuses hidden everywhere, in practically every compartment. I wish they had been a little more disciplined about that.
 
On the AT34, there are breakers and fuses hidden everywhere, in practically every compartment. I wish they had been a little more disciplined about that.

Hidden fuses on any boat....:banghead: This become a greater problem as the boat ages and owners' modify and add assessors.

The AT seemed to have grouped up most of the fuses behind the main breaker panel. Thankfully most of the fuses are identified too. I will admit there are some hidden fuses for the nav system. They seem to be located behind the dashboard.
Compared to my old Nordhavn, my AT is a dream.
 
Thanks all - put a blanket over the PVs and pulled the plugs. Worked like a charm and was able to disconnect the batteries with no issues. Putting in a quick disconnect is on the list for future upgrades!
 
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