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Pollak Circuit Breaker - Cycling/Automatic Reset - 40 Amp - Straight Mount Bracket

Pollak Circuit Breaker - Cycling/Automatic Reset - 40 Amp - Straight Mount Bracket

Item # PK54540
Our Price: $6.94
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Shipping Weight: 0.07 lbs
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This single-pole, thermal circuit breaker features a continuous cycle with an automatic reset. Breaker prevents battery from draining and auxiliary application from overdrawing. Typically used on hot leads. 1-800-940-8924 to order Pollak accessories and parts part number PK54540 or order online at Free expert support on all Pollak products. Great prices and Fastest Shipping for Pollak Circuit Breaker - Cycling/Automatic Reset - 40 Amp - Straight Mount Bracket. Accessories and Parts reviews from real customers.
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  • Reviews (43)
  • Q & A (0)
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Pollak Accessories and Parts - PK54540

  • Wiring
  • Circuit Breaker
  • Pollak
  • 40 Amp

This single-pole, thermal circuit breaker features a continuous cycle with an automatic reset. Breaker prevents battery from draining and auxiliary application from overdrawing. Typically used on hot leads.


  • Metal housing with straight mounting bracket
    • 2-Piece design
    • Attached by spot welding
  • Cycling automatic reset
    • Cycles continuously during over-current condition
    • Returns to run mode when source of over-current is removed
  • (2) 10-32 Studs
    • Yellow, dichromate (copper color) plating on battery terminal
    • Zinc plating (silver color) on auxiliary terminal
  • Straight mounting bracket
  • SAE Standard J553 compliant


  • Applications: Accessory circuit, cooling fan, door locks, headlamps, tail lamps, window lift, sunroof, trailering package, electric brake controls
  • Terminal dimensions: 0.66" long
  • Current rating: 40 DC amp
  • Voltage rating: 12 VDC (Voltage Direct Current)
  • Operating temperature: -10 degrees F (-23 degrees C) to 150 degrees F (65 degrees C)
  • Storage temperature: -20 degrees F (-29 degrees C) to 200 degrees F (93 degrees C)
  • 1-Year limited warranty

54-540 Pollak Single-Way, Thermal Circuit Breaker - Cycling/Automatic Reset - Straight Mounting Bracket - 40 Amp

Alternate to 9510

Customer Satisfaction Score:

Customer Reviews

Pollak Circuit Breaker - Cycling/Automatic Reset - 40 Amp - Straight Mount Bracket - PK54540

Average Customer Rating:  4.9 out of 5 stars   (43 Customer Reviews)

This single-pole, thermal circuit breaker features a continuous cycle with an automatic reset. Breaker prevents battery from draining and auxiliary application from overdrawing. Typically used on hot leads.


Added this fuse to the TOAD vehicle for the battery charge while towing.


Worked perfect in my dump trailer to replace a burned up one. Still working right a year later.


Item is just what we wanted and ordered. It came pretty quick. Satisfied customer here :)

by: has been an easy company to work with. They were helpful in making sure we had what we needed to install our trailer hitch successfully. Thank you for your help. We have recommended you to friends and family and will continue to do business with you in the future.

Debbie H.


Still a great product and a great company!


All things listed were required although the terminals did not have a large enough opening as I needed. Also, it said that I needed 10 gauge wire but my Chevrolet is wired with 14 gauge so I have to modify the wiring. The idea was to hot wire the 12v pin on my stock 7 pin connector to supply my trailer with the necessary 12v to charge the trailer battery when on the road. However, after checking the stock wiring, I found it to be in good condition so I was able to reuse the existing stock wiring which was still in the stock wiring harness to the 7 pin hitch at the rear of my vehicle. I was able to pull the existing 12v wire off of the 12v pin in the fuse box and attach it to the new Pollack circuit breaker I purchased from I then only needed to use about 1 foot of the 10 gauge wire to go from my battery to the other pole of the Pollack circuit breaker. Very simple procedure sine I didn't have to run the 10 gauge back to the rear of the vehicle and attach it to the existing 14 gauge wire I had. The third picture I've posted with the red and blue wires next to each other show you the 10 gauge blue wire I purchased and the 14 gauge stock red wire that was in my truck.


Perfect addition to protect my Tekonsha RF Prodigy wireless trailer brake controller. Simple to install and excellent protection.


connectors and breakers to hook up my brake controller arrived in order, installed easily, and lasted 1 year so far...


Lots of purchases from etrailer. They have the parts I need at the best prices. And the technical info I need to get the job done.



A year later and all my etrailer products still working.


Made my connection to a F150 for the brake controller very easy. The staff at Etrailer is to be commended as to how helpful they were with my hookup, on a Sunday no less. Outstanding customer support. Thank you!


Thanks for the detailed help with the wiring harness and wiring tips for my Nissan Pathfinder. This made the installation a breeze.


I rated the product in the middle category because until the charging system fails, I will not know how well this device works.


Used this in a circuit to wire in my truck to charge my travel trailer battery while driving on the road. Works great.


Great service as always!! Fast delivery! Etrailer has it all covered with product and install information, they make it easy!!


perfect replaement


Item was purchased to replace circuit breaker on a backhoe. It was cheaper then backhoe dealer,seems to be the same thing. I will try it,hope it works like I think it will.


Works as designed. Another great product from etrailer

Neal B.


Product works as designed. Havent had any issues with it at all.


The customer service I received was second to none. William was very knowledgeable in ever aspect of my purchase. Hitch is of high quality and good appearance. Will definitely buy their again.


Great product, exact replacement in my loader. Hard to get the old one out.


Works good with my application.

James C.


Working great


Install couldn't be easier. Delivery was fast. Video showed everything I needed to know.
Thanks etrailer


Easy installation. Super easy to use.


Product as described, works in my appli cation.


Does what is designed to do.

Clint M.


Still working just as its supposed to.


Job done right!

Karl W.


Perfect... reliable...


I have not performed my installation yet but this is to compliment you on your order processing and shipping. This is my second order and everything was well packaged and delivered right on time. I recommend your site to people all the time. Thanks!

Show More Reviews

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  • How to Wire the 7-Way Charge Wire to Trailer Winch Battery and Protect the Vehicle Battery
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Info for this part was:

Employee Mike L
Expert Research:
Mike L
Employee Jameson C
Expert Research:
Jameson C
Employee Adam R
Expert Research:
Adam R
Employee Tyler C
Written by:
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Employee Joshua S
Video Edited:
Joshua S
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