Review system plan, can CT wires be extended?

[vilord]

Hello!

I am in the process of figuring out what to buy.
I ordered a Curb, but then canceled the order once I realized that I would need more than 18 circuits and I didn't want to buy a whole extra Curb.
So, probably going with a single GEM system with dashbox.
I'd like to use pulse counters to monitor the gas and water meters.

My main panel is a 30/200, so i'll need two split 200s.

For 240v breakers, there is a 40amp circuit to the range, 30amp circuit to the main house AC compressor, 30 amp circuit to a clothes dryer, 20amp circuit to the air handler, 20amp circuit to a small jet bathtub, and another 20amp circuit to a smaller minisplit, as well as a 50amp circuit to a sub-panel that's about 50 feet away.
The remaining 16 circuits are single breakers, all 20amps or less.

Inside the sub-panel is a 240v 50amp circuit to a hot tub, a 240v 30amp circuit to a second electric dryer (surprisingly, the hot tub and dryer have never been on at the same time to trip the subpanel's feed), and two 120v 20amp circuits.

For the main panel, I think I'll need 8 mini 40s for the 240v circuits (excluding the sub feed), and another 16 mini 40s for the 120v circuits.
For the sub panel, I'd need 4 mini 40s and 2 mini 50s.

My questions:
1) does this sound right?
2) can I extend the wires on the CTs by 50 feet and still get accurate readings? I don't want to buy a whole extra GEM just for 4 circuits, but I also want to know the accurate power usage of the hot tub, as that is one of the main reasons I'm heading down the path of monitoring at all... seeing the sum of hot tub and dryer wouldn't be as useful to me.
3) should I go with mini 50s for the electric range, since the -40s would be near their limit and therefore less accurate?

Thanks!

[ben]

1) 2 CTs for any unbalanced 240V load, 1 CT for balanced. If you've taken that into consideration, your CT counts look fine (given the 8 Micro-40s for the 240V vs the 6 circuits).

2) Shouldn't be an issue. Use CAT cable to reduce noise. Hot tubs are brutal for power use.

3) If the Micro 40s fit the wire diameter they'll be fine. A breaker is rated for 80% of its usage so it doesn't pop, so a 50A breaker shouldn't pull more then 40A.