Interconnection & the 120% rule — NEC 705.12
Whether a given back-fed solar breaker is legal on a given busbar and main, and what to do when it is not. 35 worked scenarios, each computed by the same NEC engine that sizes a real OneLine Studio permit set.
- What Size Solar Breaker Can You Back-Feed Into a 100 A Panel With a 50 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 100 A Panel With a 60 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 100 A Panel With a 70 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 100 A Panel With a 80 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 100 A Panel With a 90 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 100 A Panel With a 100 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 125 A Panel With a 70 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 125 A Panel With a 80 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 125 A Panel With a 90 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 125 A Panel With a 100 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 125 A Panel With a 110 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 125 A Panel With a 125 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 150 A Panel With a 80 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 150 A Panel With a 90 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 150 A Panel With a 100 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 150 A Panel With a 110 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 150 A Panel With a 125 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 150 A Panel With a 150 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 200 A Panel With a 100 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 200 A Panel With a 110 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 200 A Panel With a 125 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 200 A Panel With a 150 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 200 A Panel With a 175 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 200 A Panel With a 200 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 225 A Panel With a 125 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 225 A Panel With a 150 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 225 A Panel With a 175 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 225 A Panel With a 200 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 225 A Panel With a 225 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 400 A Panel With a 200 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 400 A Panel With a 225 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 400 A Panel With a 250 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 400 A Panel With a 300 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 400 A Panel With a 350 A Main?
- What Size Solar Breaker Can You Back-Feed Into a 400 A Panel With a 400 A Main?
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