Critical Loads Panel Wiring question

AmpLee

Solar Enthusiast
Joined
Jun 1, 2020
Messages
43
DE644E27-2BCB-4F74-9032-6D67C61AF7B0.png

The above image is from the Sol-Ark manual. It shows a hot red wire going from a breaker in the transfer switch to the breaker in the main panel. However, when watching Gain Solar’s video on wiring a critical loads panel here...
It seems that he does not retain a breaker in the main panel to which connect a hot red wire from the critical loads to main panel (only pig-tailing the hot black wire).

so my questions...

Is the difference due to one being a transfer switch and one being a critical loads panel (Sol-Ark instructions doesn’t make a distinction here)?

Does wiring a critical loads panel like done in the Gain Solar video affect the limited to home use in the Sol-Ark 12k?
 

OffGridInTheCity

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May 23, 2021
Messages
450
Location
Southern Oregon
The youtube is showing a different (multi-panel) setup than the Sol-Ark diagram. The Sol-Ark diagram is similar to what I run - e.g. "just" the main panel with MTS. Here's my setup - the ATS = Sol-Ark for purposes of this comment. The Pro/Tran 2 is the MTS.
1626793606217.png

>The above image is from the Sol-Ark manual. It shows a hot red wire going from a breaker in the transfer switch to the breaker in the main panel.
When you say "transfer switch" in this sentence - I'm not sure if you meant the Sol-Ark ATS or the Line/Gen MTS.

The MTS wiring to a main panel is completely different than running main panel power -> Sol-Ark (240/120v) and the Sol-Ark -> MTS (240/120v). The MTS wiring (in Sol-Ark diagram and in my system) is all about adding it's own breakers in a cooperative way with the main panel breakers... for several individual circuits... so you can choose Gen (power goes thru the MTS breaker) or Line (power goes thru the main panel breaker as it would have without the MTS). In my MTS case - 8 of the circuits are 120v only and 2 of them are tandem/240v. The wire coloring of an MTS not the same scheme as standard 240 black/red/white/ground :)

In the MTS case you bring in
1) A wire from the circuit of the main panel (by disconnecting it from the original circuit breaker in the panel)
2) Power from the ATS (either main panel or Sol-Ark/inverter)
3) And then hook them into the MTS - so the Line Switch position is powered by the original circuit and the Gen Switch position is powered by Sol-Ark ATS
4) Then run a wire back out to the original circuit breaker.
*Something like the above - there should be specific hookup diagrams for your situation / the MTS itself should have very explicit hookup diagrams.
 
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AmpLee

Solar Enthusiast
Joined
Jun 1, 2020
Messages
43
The youtube is showing a different (multi-panel) setup than the Sol-Ark diagram. The Sol-Ark diagram is similar to what I run - e.g. "just" the main panel with MTS. Here's my setup - the ATS = Sol-Ark for purposes of this comment. The Pro/Tran 2 is the MTS.
View attachment 57016

>The above image is from the Sol-Ark manual. It shows a hot red wire going from a breaker in the transfer switch to the breaker in the main panel.
When you say "transfer switch" in this sentence - I'm not sure if you meant the Sol-Ark ATS or the Line/Gen MTS.

The MTS wiring to a main panel is completely different than running main panel power -> Sol-Ark (240/120v) and the Sol-Ark -> MTS (240/120v). The MTS wiring (in Sol-Ark diagram and in my system) is all about adding it's own breakers in a cooperative way with the main panel breakers... for several individual circuits... so you can choose Gen (power goes thru the MTS breaker) or Line (power goes thru the main panel breaker as it would have without the MTS). In my MTS case - 8 of the circuits are 120v only and 2 of them are tandem/240v. The wire coloring of an MTS not the same scheme as standard 240 black/red/white/ground :)

In the MTS case you bring in
1) A wire from the circuit of the main panel (by disconnecting it from the original circuit breaker in the panel)
2) Power from the ATS (either main panel or Sol-Ark/inverter)
3) And then hook them into the MTS - so the Line Switch position is powered by the original circuit and the Gen Switch position is powered by Sol-Ark ATS
4) Then run a wire back out to the original circuit breaker.
*Something like the above - there should be specific hookup diagrams for your situation / the MTS itself should have very explicit hookup diagrams.

In my setup, I'd be running the main panel and a critical loads panel like in the video and not using a multi-circuit transfer switch like in the manual (and your setup). I just wasn't sure if the wiring was the same on a critical loads panel as on a multi-circuit transfer switch since above the image in the manual it uses both terms even though it only displays the wiring for the MCTS. Thanks for the breakdown of your system it helps clarify things!
 
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