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Commercial Breakers:
    Circuit Breaker
1–35 Amp
2EP Series
    Circuit Breaker
2–40 Amp
C Series
    Circuit Breaker
12.5–60 Amp
7851, 7854
    Circuit Breakers
35–150 Amp
F Series
    Circuit Breakers
35–150 Amp
    Circuit Breaker
35–150 Amp
S Series
    Circuit Breaker
Precision Breakers:
    Circuit Breaker
2–35 Amp
PS series
    Circuit Breaker
2–40 Amp
Small Frame P
    Circuit Breakers
    Circuit Breaker
35–150 Amp
Large Frame P
  Contacts / Distributors

Site Updated February 16, 2018

* * * Sensata > Products > Klixon Brand > Circuit Breakers > Thermal >

Klixon® 7851 and 7854 Series Thermal Circuit Breakers
12½ to 60 Amp, Commercial, Sealed, Ignition Protected

Overview Data Sheet (PDF) Request Pricing or Info

12.5 - 60 amps
Commercial thermal circuit breaker
Ignition protected

Similar in construction to the C Series device. Incorporation of the standard stud type terminals affords the design engineer additional design flexibility beyond the screw type terminals found in the C series breaker.

Using a bimetal, snap–acting disc as the sensing and actuating element, this thermal circuit breaker provides trouble free over–current protection for harsh environments.

This device is available in two configurations:
7851: Sealed construction, manual reset (pushbutton)
7854: Sealed construction, automatic reset


Accessory and equipment protection for stern–drive marine engines and other marine applications requiring ignition protected devices
Battery protection in electric vehicles

General Envelope Dimensions
Nominal dimensions provided for reference only.

Side View of 7851 (pushbutton omitted for 7854):

Views of 7851 circuit breaker

Bottom View of 7851 and 7854:

Views of 7851 circuit breaker
* * *
Klixon 7851-13-40

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Trip Curve
Approximate Time — Current Characteristics at 77°F (25°C)

Trip Curve Diagram

Solid Lines: 7851 and 7854 (above 10 Amps), C series, 6790 Series (above 20 Amps)
Dotted Lines: C series (10 Amps and below), 6790 series (20 Amps and below)

Derating Curve
Approximate Effect of Ambient Temperature on Ultimate Trip

Diagram: Approximate effect of ambient temperature on ultimate trip
Performance characteristics are based on room temperature (77°F). Consult derating curve at left for ambient temperatures significantly higher or lower than standard room temperature.

Example: At 77°F the device is calibrated to hold at 100% of rated current (1) and trip at 135% of rated current (2). At 140°F, the same device will hold at approximately 78% of rated current (3), and trip at approximately 115% of rated current (4).
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