Check out table 310.16. in the National Electrical Code. If all of the
terminals are rated for 75 degrees Celsius, than you can install a 50 amp
circuit breaker. The electrician probably should have run a 60 amp line
since that is what the nameplate says is the maximum. You might want to put
an ammeter on the line to see how much current the unit is actually drawing.



"Joey_Bitchn'" wrote in message
...
Greetings could someone post an anwser to the group for the following:

I have a home that is about 20 years old. The sub-panel in the
basement is a 100 AMP panel. I have an aluminum wire that runs from
the panel to a new airconditiong unit I had installed recently. The
wire reads:
SE Cable Style U Type XHHW CDRS 600V 3 CDRS 6 AL (UL) 1983

I currently have a 40 AMP breaker installed that keeps tripping after
the AC unit cycles on and off a few times. The AC guy that installed
it said to put in a 50 AMP breaker but I can't find the information to
see if this wire can take that size breaker. If someone can help me
find the info or if you know for sure that a 50 AMP breaker is OK,
could you please let me know?

PS The AC unit says it can take a max breaker of 60 AMP.

Thanks

Joe