I have a 400Amp service with 2 200Amp disconects. Can I put doouble barel lugs on 1 disconect to feed 1 200Amp panel and feed 100Amp back fed breaker.
Thanks H2O
My answer would be yes assuming your load is appropriate. Assuming also you are not overloading the 200a. overcurrent device and the 100a breaker is secured in the panel by a Listed clip.
The only joker in the deck is that the wire to the 100 amp panel should be sized for 200 amps, unless you can apply tap rules to your circumstance. Otherwise, there might be a problem fitting the wire into the breaker.
Reno- If I'm reading his post correctly, this would be a tap to a 200a Service switch. Since he is on the load side of fusing, we are talking feeder. In his case there are no actual feeder conductor, only double barrel lugs. This happens sometimes. Since he is terminating in a 100a overcurrent device he could use 100a. wire. The code reference could be 240.21(B)(1). There is no way he could overload the 100a. conductors since there protected due to the tap limitation mentioned above.
I think Reno may be referring to the raceway requirements and 25' length restrictions for taps. The ampacity part is OK if this is a legal tap.