The NFW2-100 detects ground faults by monitoring for a zero impedance condition between the control panel and earth ground (Page 125) [1].
When a fault is detected, a dedicated yellow Ground Fault LED flashes on the main circuit board to notify the technician (Page 125) [1].
Key operational details include:
Continuous Monitoring: The panel automatically checks for ground faults at regular intervals while operating in Normal mode (Page 126) [1].
Disabling Detection: To disable ground fault detection, the jumper or shunt must be removed from JP7 on the main circuit board; this typically requires approval from the local AHJ (Page 9) [1].
EIA-232 Connection: Technicians must ensure no ground faults exist before connecting a printer or PC to the EIA-232 port (TB8). The connection itself may cause a ground fault depending on the external device, and pre-existing faults can result in circuit damage (Page 36) [1].
