![]() In the event of a ground connection failure and internal leakage within the mobile equipment, it is possible for the frame of the equipment to become live and present a shock hazard.įor added protection, the GCHK-100 detects high equipment frame voltages and quickly trips the relay. ![]() The GCHK-100 monitors the loop resistance of the two grounds and trips when it exceeds a preset value.Īdditionally, the relay will detect if the ground loop has become shorted or has opened. Operator safety from electrical shock depends to a large extent on the integrity of the grounding of the equipment when it is energized. It is vital, therefore to know if this grounding has been compromised to do this a second auxiliary ground conductor is incorporated in the trailing cable to the mobile equipment. Wide range AC and/or DC control voltage. ![]() Suitable for solidly grounded or resistance grounded systems, three phase or single phase loads.Due to its very low sensitivity (down to 10ma) the mGARD is ideal for people safety in areas wherever the public is exposed to water and electricity such as water parks and fountains.The mGARD-SYM provides detailed device status information. The relay can be connected to the mGARD-SYM remote indicator (with Modbus connectivity) for remote test/reset and monitoring. With the harmonic filter disabled, the relay will respond to AC currents between 25 and 400Hz. This can be used to eliminate false tripping when the relay is used on systems with variable frequency drives. The mGARD reacts to alternating current only and will reject direct current signals. With the harmonic filtering feature enabled, the mGARD rejects all higher frequencies than fundamental. Options are available for operation at 5 VDC, 12 VDC and 24 VDC. The mGARD operates on any control voltage from 40-240 volts direct current (DC) or alternating current (AC), and contains an isolated power supply. The I-Gard mGARD is a microprocessor based ground fault relay designed and built to be used on solidly grounded or resistance grounded systems. This innovative digital electronic relay measures ground fault current using built-in zero sequence current sensor (ZSCS). However, the modern relay can be programmed to prevent this and only shunt-trip the lesser priority feeder, leaving the more important feeder on-line. In the event that a second ground fault occurs prior to removing the first ground fault, a phase-to-ground-to-phase or phase-to-phase fault can occur. When this occurs on the original HRG, it would cause both feeder circuit breakers and possibly the main circuit breaker to trip. The purpose is to continually remind maintenance personnel to either remove the ground fault or to reset the timer every so many hours. Unless the ground fault is removed or the timer is reset, the faulted feeder is shunt-tripped offline. Since the zero-sequence current transformers identify the faulted feeder, the relay has the ability to begin a (user programmable, usually in hours) timer when the ground fault first occurs. There is a concern that the first ground will be left on the system and ignored. The DeadEasy 3 phase mains indicator was designed to provide non-electrical people with a simple and safe method of verifying MCC (Motor Control Centre) based, electrical isolations before conducting mechanical maintenance.Ĭlick through to our website to see a video of DeadEasy phase indication in action, device pricing and online ordering information.The original HRG system developed in the 1950’s and 1960’s provided process continuity, however, they were unable to solve potential safety issues, such as a second ground fault, leaving the ground on the system too long and monitoring of the neutral path. Non-contact voltage sensing to detect the presence of power circuit voltage– does not compromise the integrity of the power system This 3 phase indicator is primarily used to verify safety isolations as part of a lockout procedure.ĭeadEasy is different because it incorporatesĪ true self test function – user activatedįail safe, positive indication – illuminated LED when the disconnect or isolation switch is off DeadEasy is a switchboard mounted, voltage indicator that includes a self test function.
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