Solar panel disconnect switch

[admin-rich]

After installing Lithium batteries I wanted the ability to take them off charge so that they would not have a continuous charge on them.
The camper came with lead acid batteries installed.  Continuous charging from the solar panel(s) was okay then.
And it's okay with Lithium iron phosphate batteries too - except that its not optimal for long battery life.

Besides, I wanted a safe simple way to take the solar current off line.
And I didn't want a BIG surface mounted on/off switch - like the big Marine battery switches.

I've seen my solar panels deliver a 15 a/h charge on a good day.
And the solar charge controller is rated for 30 amps.
So I needed a switch capable of 30 amps.

My final choice was a Cole Hersee 2484 Master Disconnect Switch
Investigating this switch, I found the technical specs on the Cole Hersee website where they state that the "specs" are very conservative.
(20A at 12V continuous - 125A @ 12V intermittent)
I'd say so, considering the size of this beast:
   
 
I've wall mounted it in an inconspicuous spot (behind the paper towel holder).
   
Finished:
   

[3 tons]

After installing Lithium batteries I wanted the ability to take them off charge so that they would not have a continuous charge on them.
The camper came with lead acid batteries installed.  Continuous charging from the solar panel(s) was okay then.
And it's okay with Lithium iron phosphate batteries too - except that its not optimal for long battery life.

Besides, I wanted a safe simple way to take the solar current off line.
And I didn't want a BIG surface mounted on/off switch - like the big Marine battery switches.

I've seen my solar panels deliver a 15 a/h charge on a good day.
And the solar charge controller is rated for 30 amps.
So I needed a switch capable of 30 amps.

My final choice was a Cole Hersee 2484 Master Disconnect Switch
Investigating this switch, I found the technical specs on the Cole Hersee website where they state that the "specs" are very conservative.
(20A at 12V continuous - 125A @ 12V intermittent)
I'd say so, considering the size of this beast:

 
I've wall mounted it in an inconspicuous spot (behind the paper towel holder).

Finished:

Rich, With Lithium (LFP) in a storage scenario, it’s definitely a Smart move to have a shut-off switch, but know that ‘certain’ solar controllers (like my BlueSky - not too sure about others…) require a connection to the battery (battery connection is a part of the controller loop), else damage will occur…My fix (‘before’ shutting off battery) was to fully isolate the controller by installing a second shut-off switch between the controller and the panels….Just saying

[admin-rich]

To clarify, the switch was installed between the solar panels and the controller.
The batteries are still powering the camper without a solar charge applied to them.
And, I'm pretty sure, most campers have a battery cut-off switch.  At least my old Eagle Cap used to have one.

[Craig]

Just joined and as I was scanning various articles, I came across this one.  We had lithium batteries installed as part of the delivery of our 2022 1200 (that's a long story!), and later learned about the issues discussed here.  I ended up putting a Blue Sea Systems shutoff switch up near the ceiling above the solar controller interrupting the negative feed from the solar panels to the controller.  It turned out that the battery shutoff supplied with the camper didn't really cut off all the load(s) to the battery bank, so I added another Blue Sea Systems shutoff switch on the left (looking in the access door -- passenger side) basement sidewall in front of tanks (gray & black), again in the negative feed from the battery bank before ANYTHING else and then used terminal blocks on the floor for all the positive and negative leads for the various loads (e.g. power converter, generator starter, etc.).  I turn the battery switch on and then the solar panel switch before I start doing anything with the camper and turn them off in the reverse order (solar switch first) when closing up for storage/idle time.

[3 tons]

Just joined and as I was scanning various articles, I came across this one.  We had lithium batteries installed as part of the delivery of our 2022 1200 (that's a long story!), and later learned about the issues discussed here.  I ended up putting a Blue Sea Systems shutoff switch up near the ceiling above the solar controller interrupting the negative feed from the solar panels to the controller.  It turned out that the battery shutoff supplied with the camper didn't really cut off all the load(s) to the battery bank, so I added another Blue Sea Systems shutoff switch on the left (looking in the access door -- passenger side) basement sidewall in front of tanks (gray & black), again in the negative feed from the battery bank before ANYTHING else and then used terminal blocks on the floor for all the positive and negative leads for the various loads (e.g. power converter, generator starter, etc.).  I turn the battery switch on and then the solar panel switch before I start doing anything with the camper and turn them off in the reverse order (solar switch first) when closing up for storage/idle time.

Good move Craig!

For a battery disconnect, I went this route - Though this is low-tech switch, it’s good for whopping 500 amps, inexpensive, easy to install and effectively isolates the LiFePo4 batteries during short or long term storage…

https://www.amazon.com/Battery-Akozon-Di...Y2s9dHJ1ZQ==

3 tons

[admin-rich]

Amazon has it's size listed as:

Item Dimensions LxWxH  0.39 x 0.39 x 0.39 inches

Is this correct?  It looks a lot bigger.
At any rate, it looks like a good quick disconnect for the battery.  (though I'm not keen on knife switches)


  knife_switch.jpg (Size: 9.75 KB / Downloads: 11)

[3 tons]

Amazon has it's size listed as:

Item Dimensions LxWxH  0.39 x 0.39 x 0.39 inches

Is this correct?  It looks a lot bigger.
At any rate, it looks like a good quick disconnect for the battery.  (though I'm not keen on knife switches)

Yep, that’s it, knife switches are uber robust and are what is used in locomotives and various industrial equipment….It is depicted in the picture on a smaller sized battery…