Include 240VAC on Critical Load Panel?

[SoTxUser]

I have a weird question. I got an 18KPV grid tied via feeder line taps with a 10 circuit CLP. All circuits on the CLP are 120V although the first 4 circuits can be doubled for 240V at 30amps (2 20amp breakers on circuits 1&2 and also 3&4).

My current setup for critical loads is near perfect right now but I'm adding a second 6 circuit CLP for non critical loads. Non critical like landscape lights, garage lights, empty bedrooms, etc. Some of these circuits are on CLP #1. Removing 4 of these from CLP #1 will allow me to add two 240V loads to the panel. The only small load 240V items I have are 1) Stove (10KW), clothes dryer (5400W) and AC compressor (30 amp breaker... normally runs at 1500 to 2500 watts. It's a variable speed 5 ton). I don't want AC on critical loads but I can add the clothes dryer and stove... not because I need them but to balance the load... somewhat! But since I'm back feeding does it really matter? On a normal non winter day the 18KPV powers the entire house. FYI... my water heater is on demand 24KW (normally runs at 5 or 6KW) and home heating is 5 to 15KW (3 stage). The 18kpv can't run the house in the winter but we have short mild winters.

Thanks for an insight.

tsp

 

[WorldwideDave]

is the question whether or not you can run those 240V loads from your critical loads panel?
When you say back feeding, you mean your solar is connected to a critical loads panel, and anything not in use (overages) produced by your inverter is back feeding into the house's main panel? I hope you are not back feeding into the meter/grid - you could kill a lineman that way.

 

[SoTxUser]

is the question whether or not you can run those 240V loads from your critical loads panel?
When you say back feeding, you mean your solar is connected to a critical loads panel, and anything not in use (overages) produced by your inverter is back feeding into the house's main panel? I hope you are not back feeding into the meter/grid - you could kill a lineman that way.

Sorry for not being clear.
I know I can run 240V circuits on my critical loads panel. The question is if there is any value in doing that since few, if any, 240V circuits are critical in my case but will it better balance loads if I had a couple of 240V loads on the panel? And to clarify, I'm adding a 2nd CLP that is off grid that is 100% 120V loads. The main CLP is a 50 amp unit. The 2nd CLP is a 30 amp unit. Unit #1 can only drive small 240V loads like my stove and clothes dryer.

My system is setup for self consumption... loads first then battery charging and then grid feedback. I am officially grid tied. Not to make money but simply to not waste solar power. I am on a plan that has on peak and off peak rates. I very seldom use any grid during on peak times (have a 30KWh bank). To be legal, the system cuts back feeding the grid when the grid is down but continues to power my CLP.

Hope I'm not thrashing with this issue. (thrashing used in the computer science sense)
I can just let the system run and off load a few other loads on to CLP #2 and everybody's happy.

tsp

 

[WorldwideDave]

you should probably find out what the loads are - power audit - before deciding which loads (branch circuits) are connected to which breakers on which leg of the hots.

 

[Steve777]

So you have 240VAC in your CLP, as you say. Which means almost certainly the 120VAC breakers will alternate as to which leg/line (L1 or L2) of the 240VAC they go on as you go up/down the columns. You can see this as the aluminum or copper buss bar the 120VAC CBs plug into alternate. When you plug a 240VAC breaker in, it is really just 2 120VAC breakers stuck together and with their levers connected so they both pop off at the same time; they go to both lines (L1 and L2).

Point is, you can be balanced, between the two 120V legs/lines that make up 240VAC (L1 and L2), with either 120V CBs or 240V CBs. It just depends on the loads and how they are connected. Maybe easier with all 240V loads, but not necessarily. You might be balanced now with just the 120V CBs, just depends on the loads, how they are used and which side (L1 or L2) their CBs are on.

If your inverter reports power used by L1/L2, or if you have power monitoring SW which does, you can see how well balanced the current setup is or isn't. If it isn't balanced well enough, you can probably fix it by moving the 120V CBs to/from the lines they are on now. Not sure that you need to move some 240v load in there, at least for balancing purposes.