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Manual Button Reset Fault Indicator

Manual Button (MB) Reset Fault Indicators use a magnetic field from the fault current to act as an over center magnetic toggle to produce fault indication. No mechanical triggers or latches are used. The MB display features a reflective target that is either red or white. A faulted line condition is displayed by the red target, while a normal condition is displayed by the white target. The MB is reset by pressing a magnetic button integral to the indicator, thus making removal from the line unnecessary for reset.

Both Manual Reset (MR) and MB Fault Indicators have hermetically sealed, ultrasonically welded housings and stainless steel, vinyl-coated clamping mechanisms that make them suitable for use in harsh, submersed, and corrosive environments.

Test and Reset Tools for Fault Indicators

Starting At

$43 USD

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After a fault occurs, use an MB or MR before reclosing for inexpensive, efficient fault location.

The MB is line-powered and battery free.

The built-in reset button in the MB model eliminates the need for a separate reset tool.

MB models are only for underground applications.

SEL fault indicators have more than 50 years of field-proven reliability.

Nominal Trip Ratings200 to 800 A
Trip Tolerance±10%
System Voltage Range—UndergroundMatches the URD Cable Rating
Maximum Fault Current25 kA for 10 Cycles
Trip Response Time8 ms
Outer Diameter Clamping Range0.25" to 1.4" (Please Specify the Clamping Diameter or Range When Ordering)
Temperature Range—40° to +85°C
Approximate Weight170 g (0.37 lbs)


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