Insulation Test

DANGER
Hazard of Electric Shock, Explosion, or Arc Flash Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices. See NFPA 70E, NOM-029-STPS-2011, or CSA Z462. This equipment must only be installed and serviced by qualified electrical personnel. Turn off all power supplying this equipment before working on or inside equipment. Always use a properly rated voltage sensing device to confirm power is off. Replace all devices, doors, and covers before turning on power to this equipment. Failure to follow these instructions will result in death or serious injury.

DANGER

Hazard of Electric Shock, Explosion, or Arc Flash

Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices. See NFPA 70E, NOM-029-STPS-2011, or CSA Z462.
This equipment must only be installed and serviced by qualified electrical personnel.
Turn off all power supplying this equipment before working on or inside equipment.
Always use a properly rated voltage sensing device to confirm power is off.
Replace all devices, doors, and covers before turning on power to this equipment.

Failure to follow these instructions will result in death or serious injury.

NOTICE
HAZARD OF OverVoltage Do not use a megohmmeter on: — adjustable speed drives — solid state soft starters — surge protection devices (SPDs) — AccuSine™ active harmonic filter units — PowerLogic™ solid state meters — capacitor units — any devices not designed to withstand megohmmeter voltage. Disconnect all solid state devices such as SPDs, drives, soft starts, capacitors, filters, and circuit monitors before performing megohmmeter tests on the MCC. Failure to follow these instructions can result in equipment damage.

NOTICE

HAZARD OF OverVoltage

Do not use a megohmmeter on:
— adjustable speed drives
— solid state soft starters
— surge protection devices (SPDs)
— AccuSine™ active harmonic filter units
— PowerLogic™ solid state meters
— capacitor units
— any devices not designed to withstand megohmmeter voltage.
Disconnect all solid state devices such as SPDs, drives, soft starts, capacitors, filters, and circuit monitors before performing megohmmeter tests on the MCC.

Failure to follow these instructions can result in equipment damage.

Before an MCC is energized, take resistance measurements. Use an insulation tester (megohmmeter) with a potential of 500–1000 V. Take readings between each phase and from each phase to ground, with the branch disconnects off. Make sure the main disconnect is off during all insulation tests.

Readings from a megohmmeter with all disconnects off will typically be 5–20 megohms or higher. Do not energize the MCC if readings below one megohm are found. Contact your local Schneider Electric representative. Record all megohmmeter readings for future reference. Any sudden change in resistance values (even within the acceptable range) may indicate a potentially damaged insulation system. Early detection and replacement of a potentially damaged insulation system helps avoid equipment damage.