Insulation and NGR Monitoring in Mining

Electrical monitoring from the neutral resistor to mobile equipment.

NGRM700 monitors the neutral grounding resistor in a high-resistance grounded (HRG) system. RC48C evaluates the protective conductor loop and residual current in a trailing cable with a pilot wire. These products focus on different measuring points in the distribution system and mobile load.

01 · NEUTRAL GROUNDING RESISTOR MONITORING

LINETRAXX® NGRM700

Monitors the neutral grounding resistor’s resistance, the fault current through it and the NGR voltage in an HRG system. Provides alarms and status information on resistor deterioration and earth faults.

• Evaluating NGR resistance through active and passive measuring methods
• Monitoring neutral current and voltage
• Providing operational information through configured relay outputs and communication

NGRM700 technical details and documentation ↗

02 · TRAILING CABLE AND PE LOOP MONITORING

RC48C

Monitors protective conductor loop continuity in trailing cables with a pilot wire. Also evaluates residual current with a suitable measuring current transformer; open circuits, high resistance and short circuits are monitored according to the selected connection arrangement.

• Monitoring the PE and pilot-wire loop of mobile equipment
• Operation with a suitable termination unit and current transformer
• Signalling to a suitable switching chain through an alarm relay with two changeover contacts

RC48C variants and technical documentation ↗

The diagrams show functional information flow. NGRM700 monitors the neutral grounding resistor; it is not a general-purpose earth electrode resistance tester. For RC48C, the pilot wire, termination unit, current transformer and switching arrangement are selected together according to the manufacturer’s connection diagram for the relevant variant.

Bender manufacturer sources: NGRM700 · RC48C · Mining brochure · PDF p. 5