48V DC Earth Leakage Alarm Relay. DC Earth leakage Relay responding to a negative or positive earth fault will illuminate the appropriate led on the unit facia indicating which pole is earthed. The DC Earth leakage Relay is not suitable for use in vehicles using a positive or negative earthed chassis for obvious reasons (special automotive versions are available for vehicle applications including electric vehicles) but if you use batteries in marine applications, using the steelwork as a conductor is not desirable and this unit can detect this unwanted condition.
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