Circuit Breaker not breaking - ETA

Sep 1, 2014
37
Catalina 30 MKII Gulfport, FL
Have ETA Circuit breakers in my panel, and was finding they were NOT breaking when I had excessive loads, and wire was getting hot on the panel. Figured breaker was bad. Had no problem getting new ones (Allied Electronics), as specs are on each breaker. ETA also has a chart explaining the part number codes. Additionally upgraded to heavier wire, for less worry.

Anyway, new ones weren't breaking either - put a 20A load on the new 15A, didn't break. Tech support at Allied was great, and reached out to ETA (German, I think). They talked with ETA Tech Support and provided a brochure. As below chart shows, they don't break for at least 100 minutes (6,000 seconds) AFTER exceeding a load? Too much time for me to be comfortable while wires heat up and possibly melt.

Anyone else checked this out, or had issues? What am I missing here? Can't figure out why Catalina put these kind of breakers in a boat, (or where their application would be - with such a long trip time?). Note - this is all on the 120v AC side of power. Initially found this Issue when I put a space heater in the boat for cold evenings.
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May 7, 2011
281
C - 30 # 3573 Lake NormanNC formerly Bflo NY
My eyes tell me that a 20a load (1.3x the 15a breaker rating) should trip in about 40 secs, give or take.
No?

Breaker size is often set according to the equipment limits, not the wiring to the equipment. In other words, the wiring is oversized to meet voltage drop limits. You may run 10awg to a bilge pump (good for 50a or 60a, depending) but the pump might draw 10a.
 
Sep 1, 2014
37
Catalina 30 MKII Gulfport, FL
You're right at that load, based on the graph. Thanks for straightening me out. I'd run it for.many minutes in my test though, and it didn't trip. I'll run it for a longer period, ti see when it breaks. Maybe old one, which never tripped is bad, due to age.
Still surprises me that it will run at load for 90 minutes.
Am accustomed to home circuits breaking if rated load is reached.
Will probably go with a 10A breaker, for peace if mind.
 
May 7, 2011
281
C - 30 # 3573 Lake NormanNC formerly Bflo NY
I'd stick with Blue Sea breakers, although it would be interesting to see if they have a response graph like that one.

This explains how the inrush current can be many times more than the circuit capacity and therefore why breakers don't immediately trip at their rating.
 
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