Maintenance

Introduction

Safety switches are properly lubricated at the factory. However, periodic cleaning and lubrication may be required. The maintenance interval between lubrications depends on the amount of switch usage and the ambient operating conditions. The maximum maintenance interval should not exceed one year for mechanical or current-carrying parts.

For additional information, refer to publication NFPA 70B, “Standard for Electrical Equipment Maintenance”.

Unusual Performance Conditions

Contact Schneider Electric for information regarding performance under unusual conditions. Examples of unusual conditions are shown in table below:

DANGER

hazard of electric shock, explosion, or arc flash Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices. See NFPA 70E, CSA Z462 or NOM-029-STPS. This equipment must only be installed and serviced by qualified electrical personnel. Never operate energized switch with door open. Turn off switch before removing or installing fuses or making load side connections. Always use a properly rated voltage sensing device at all line and load fuse clips to confirm switch is off. Turn off power supplying switch before doing any other work on or inside switch. Do not use renewable link fuses in fused switches. Failure to follow these instructions will result in death or serious injury.

Annual Maintenance Procedures

1. Turn off power supplying the switch before performing any work on or inside the switch.

2. Open the switch blades by moving the operating handle to the OFF (O) position.

3. Lock out or tag the switch, per local procedures.

4. Open the enclosure door.

5. Always use a properly rated voltage sensing device at all line and load-side lugs (terminals) to confirm power is off.

   NOTE: Do not remove any parts from the switch or operating mechanism unless specifically instructed to do so in the following procedures. Vacuum any loose material from inside the switch. Wipe internal parts and the inside of the enclosure with a damp, lint-free cloth.

6. Visually inspect the switch for loose parts or hardware:

   1. Retighten the hardware as needed. Refer to the wiring diagram for torque values.

   2. Do not re-energize the switch if any worn or damaged parts are found. Replace them before re-energizing the switch.

Parts Removal

1. Remove the arc suppressor(s) or arc shield(s) from the switches by loosening the fastener(s) holding the suppressor(s) / shield(s) in place. See the examples provided.

2. Remove old grease and other contaminants from the line-side jaws and switchblades with a clean, lint-free cloth. If the lubricant has dried, remove it with CRC^® HF Contact Cleaner, or equivalent, sprayed on a cloth.

3. Lubricate the cleaned areas with a thin film of Dow Corning^®BG20 grease only.

   NOTE: Do not substitute any other lubricant. Other lubricants may not be suitable for electrical applications and could alter the performance of the switch. Dow Corning BG20 is available from Square D (part number SWLUB).

4. Exercise the operating mechanism to ensure proper operation by opening and closing the switch five times with the door closed. Open the switch blades.

CAUTION
HAZARD OF EQUIPMENT DAMAGE Do not disassemble the switch line base assembly or remove the blade rotor when cleaning the line-side jaw or the switch blade. See Figure 4, Examples of Line Base Assemblies. Failure to follow these instructions can result in injury or equipment damage.

Example of Arc Suppressors

Example of Arc Shields

Examples of Line Base Assemblies

Insulating Plugs on Pole Unit

Insulating plug

Parts Replacement

1. Reinstall the arc suppressor(s) or arc shield(s) according to the torque values in the table 9 below.

2. Ensure that the two insulating plugs in each phase (400–1200 A only) are firmly seated. See Figure 5.

Re-Energize the Switch

1. Close and latch the door.

2. Turn off all downstream loads.

3. Turn on power supplying the switch.

4. Turn on the switch.

5. Turn on all downstream loads.