Troubleshooting

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 or local equivalent. Only qualified personnel familiar with power switch equipment are to perform work described in this set of instructions. Workers must understand the hazards involved in working with or near power switch circuits. Perform such work only after reading and understanding all of the instructions contained in this bulletin. Turn off all power supplying this equipment before working on or inside the equipment. Always use a properly rated voltage sensing device to confirm power is off. Before performing visual inspections, tests, or maintenance on the equipment, disconnect all sources of electric power. Assume that all circuits are live until they have been completely de-energized, tested, grounded, and tagged. Pay particular attention to the design of the power system. Consider all sources of power, including the possibility of backfeeding. More than one disconnector switch may be required to de-energize the equipment before servicing. Do not remove covers, open doors, or work on the equipment unless the power is off and all circuits are de-energized and disconnected. Handle this equipment carefully and install, operate, and maintain it correctly in order for it to function properly. Do not make any modifications to the equipment or operate the system with the interlocks removed. Contact your local field sales representative for additional instruction if the equipment does not function as described in this manual or if parts are missing or damaged. Comply with all codes, standards, and regulations to promote safe electrical installations. A permit may be needed to do electrical work, and some codes may require an inspection of the electrical work. Carefully inspect your work area and remove any tools and objects left inside the equipment. Replace all devices, doors, and covers before turning on power to  this equipment. All instructions in this manual are written with the assumption that the customer has taken these measures before performing maintenance  or testing. 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 or local equivalent.
Only qualified personnel familiar with power switch equipment are to perform work described in this set of instructions. Workers must understand the hazards involved in working with or near power switch circuits.
Perform such work only after reading and understanding all of the instructions contained in this bulletin.
Turn off all power supplying this equipment before working on or inside the equipment.
Always use a properly rated voltage sensing device to confirm power is off.
Before performing visual inspections, tests, or maintenance on the equipment, disconnect all sources of electric power. Assume that all circuits are live until they have been completely de-energized, tested, grounded, and tagged. Pay particular attention to the design of the power system. Consider all sources of power, including the possibility of backfeeding. More than one disconnector switch may be required to de-energize the equipment before servicing.
Do not remove covers, open doors, or work on the equipment unless the power is off and all circuits are de-energized and disconnected.
Handle this equipment carefully and install, operate, and maintain it correctly in order for it to function properly.
Do not make any modifications to the equipment or operate the system with the interlocks removed. Contact your local field sales representative for additional instruction if the equipment does not function as described in this manual or if parts are missing or damaged.
Comply with all codes, standards, and regulations to promote safe electrical installations. A permit may be needed to do electrical work, and some codes may require an inspection of the electrical work.
Carefully inspect your work area and remove any tools and objects left inside the equipment.
Replace all devices, doors, and covers before turning on power to  this equipment.
All instructions in this manual are written with the assumption that the customer has taken these measures before performing maintenance  or testing.

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

For detail information about operation, troubleshooting, and maintenance requirements for the disconnector switch module, see the disconnector switch module manual.

Troubleshooting — High Voltage Fuses and Disconnect Switches

Problem	Probable Cause	Action
Overheating	Overload	If the excess current causes the switch to overheat, either: Replace the switch with a switch that has a rating adequate for the present load or future loads. Rearrange circuits to remove excess load on the switch.
	Poor contact (contact out of alignment)	Adjust contacts.
	Connections to switch: inadequate current-carrying capacity	Increase the capacity of the connections by adding conductors or by replacing with heavier conductors.
	Contact burned or pitted	Dress and fit the contacts properly.
	The bolts and nuts on the connections are not tight	Tighten all bolts and nuts. NOTE: Do not apply too much pressure when tightening the nuts on bolts. Using a wrench that is too large can further loosen the connection by causing the bolts to expand beyond their elastic limit. See Bolt Torque Values for Bus Connections.
	Ambient temperature too high (too close to a boiler, a furnace, etc.)	Relocate to the equipment to a cooler place or implement cooling methods.