stryped wrote in news:7fb8939d-a86a-4b09-8852- email@example.com:
Look for a maximum branch circuit breaker size printed on the tag in the panel you intend to feed from. That is the highest you can go. Guessing that you can't go over 70 or 80 amps if you want to feed out of the 100 amp garage panel.
It is a code issue. And since your initial message said the first sub panel was 50 amp I quoted 50 amp to the second panel. But with your new sub panel information the limit is 60 amp. Again a code issue. More than likely the 60 amp limit is part of the code limits for branch breakers for the 100 amp sub panel. And your service panel which I presume is 100 amp or more will have this 60 amp limit also. At any rate you can install almost any amperage sub panel but the breaker feeding the subpanel is limited to 60 amps. An additional code requirement is that the continuous load limit imposed by any panel/ load is only 80% of the breaker feeding the branch circuit. The circuit feeding the subpanel from another panel is a branch circuit from the feeding panel. The continuous load limit is usually stated as
3 or 4 hours above or at the 80% point. And more still your subpanel can be above the 60 amp limit to provide additional spaces for additional circuit breakers and the associated branch circuits.
Lots to digest but if you are not sure ask your AHJ folks for additional guidance.