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Shown on protoboard (not included)
CB500 Electronic Circuit Breaker
PN CB500: $34.99 each
In Stock!


A resettable electronic fuse (circuit breaker) that disconnects dc power to protect power sources and proto-board components. 


The CB500 Electronic Circuit Breaker is a resettable circuit breaker (or fuse) that disconnects power when the trip current is exceeded. There are 4 trip settings that can easily be changed and saved during operation. When an overload is detected, power is disconnected within 6 milliseconds protecting the power source and powered circuits from damage. Once the overload condition is corrected, the user manually resets the CB500 to restore power.


Comes fully assembled and tested. Kits are available on special order. Please refer to the assembly instructions before inquiring.



  • Replaces single use fuses.
  • Plugs into the power rails of standard prototyping breadboards. 
  • Operates with power sources between 3.5 - 16 volts dc.
  • Connect power source to protoboard power buss or input terminal block.
  • Protected power buss may be either protoboard power buss or output terminal block.
  • 4 current trip settings: 50, 100, 250 and 500 ma dc.
  • Trip response: < 6 milliseconds.
  • Three control buttons: increase trip setting, decrease trip setting and set/reset.
  • Low voltage burden: 250 mv at 500 ma setting.
  • Power requirements: 3.5-16 vdc, 20 ma.



To see if the CB500 will fit your protoboard, measure the distance between the two "+" power rails. If it is 1-25/32th inches (45.0 mm), the CB500 will drop right in and utilize the two power rails (one protected and one unprotected). If not, you can still use the CB500 by installing the lower protected buss pins only and connecting your power source to the input terminal block. All devices powered from the protected buss will be protected by the CB500.


The CB500 can be reprogrammed for special trip current settings. Contact us for details.

 Our liability is limited to the purchase price of this product only. By using this product you agree that, LLC can not be held liable for any damages or injuries resulting from use, misuse, or repair. This product is for indoor use only.