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Topic: Circuit Breaker ID (Read 506 times) previous topic - next topic

Circuit Breaker ID

On my battery isolator board there's a relay and circuit breaker for the dash air conditioner. I want to replace the circuit breaker (indicated with red arrow) but I can't make out the number on the 12v ShortStop 15 amp breaker. I see several on eBay that are 12v-15a. Anyone have the correct number and secondly, would any similar 12v 15a ShortStop suffice? Thanks.

This is one area in which I like our 320's setup much better than the 300. On the 320, FT finally tucked away the isolator board in that nice, comfy bed compartment location.
jor
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Re: Circuit Breaker ID

Reply #1 –
You just need an ordinary auto store 12-breaker. The most common are automatic reset, as opposed to manual button reset. Take yours with you to match up bracket orientation as brackets come on long ends or short ends and they come without brackets. You just need 15 amp, otherwise the main differences are in the mounting. There are also differences in the terminals, some with bolts, some with spades and some mixed.

Here is link to AutoZone (but for 40 amp):
Accessories | AutoZone.com reaker//N-2690?itemIdentifier=413268_0_0

I think you may find a couple of circuit breakers & relays on that board. Breakers and relays are cheap parts to replace, so when working on isolator panel, it may be a good idea to replace all of them. Consider new boost & start solenoids, too.

Re: Circuit Breaker ID

Reply #2 –
Hey, Barry. Muchisimas gracias. I do, indeed, intend to replace the solenoids, both breakers and both relays. Thanks for your quick reply.
jor
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Re: Circuit Breaker ID

Reply #3 –
One more question: The old solenoids have only one small terminal whereas the Cole-Hersee replacement has two. Do I run a ground wire from the second terminal on both of the new Cole-Hersees? Thanks.
jor
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Re: Circuit Breaker ID

Reply #4 –
Quote from: jor –
One more question: The old solenoids have only one small terminal whereas the Cole-Hersee replacement has two. Do I run a ground wire from the second terminal on both of the new Cole-Hersees? Thanks.
jor


Yes.

The old one grounded through the solenoid body (had to be attached to metal).  New one has separate ground terminal. 
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Circuit Breaker ID

Reply #5 –
Yep, run a ground wire to one of the small terminals.  Solenoids come in three basic types and all are pretty much the same and sometimes interchangeable.

Our common one has the internal coil grounded to the metal case, so the solenoid must be mounted on a grounded metal plate ( or a ground wire connected to a mounting bolt), and positive battery wire to the single small terminal triggers solenoid to close.

A more universal type has both sides of coil connected to separate small terminals, so solenoid can be switched with ground or positive, in our case one small terminal has to be grounded (to mounting bolt is ok). Sometimes this type has a removable clip that grounds one of the small terminals. Small terminals are not usually polarized, so If no grounded clip, either small terminal can be grounded with other terminal for positive switching.

Another more rare type has only one terminal, but the one side of the coil is internally connected to a large battery solenoid bolt, which means this type must be switched with ground. This type is the opposite of our common type above.

Here is a diagram of the three types mentioned above.

There are also different mounts, coil voltage, normally open or closed, latching and amp capacity. The attached PDF shows why what looks the same is not the same.
 

Re: Circuit Breaker ID

Reply #6 –
Thanks to both of you.
jor
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