400A & 600A Heavy Duty Safety Switch NEMA 4X, NEMA 12 Replacement Instructions for Vault Handle and Linkage Assembly

Purpose of Vault Handle The vault handle provides a handle to open and close the door. When the vault handle is latched closed (you hear a click), the door gasket is compressed against the switch body to insure the proper NEMA enclosure rating. The gasket compression must be maintained whether the switch blades are ON or OFF, so the vault handle should not be released until somebody is ready to actually open the door of the switch. The vault handle is part of a safety feature of a HD switch dual-cover interlock, as required by NEMA. If the switch is turned ON, this dual-cover interlock does not allow the door to be opened, unless defeated by a qualified person who has been properly trained to work on energized equipment and knows how to defeat the interlock. The interlock defeat consists of (a) releasing the vault handle by turning the shoulder bolt on the right front of the switch, and (b) turning the interlock defeat screw just below the switch handle. Once this has been done, the door now can be opened with the switch in the ON position.

How does the Vault Handle get damaged? If a user of the switch does not understand the operation of the switch, he or she may try to force the vault handle to turn without releasing it properly, often while the switch is in the ON position. Forcing the vault handle to turn before it is properly released will only result in causing damage to the Vault Handle and Linkage Assembly inside the switch. Once damaged, the vault handle will then simply "spin“. The switch should then be repaired for continued safe operation.

Can the Switch be fixed? Yes, the situation can be remedied by the doing the following: 1)The end users of the switch must be educated on the proper operation of the switch. 2)Replacement Parts for the Vault Handle and the Linkage Assembly can be ordered and installed per the below instructions.

To replace the Vault Handle and/or the Linkage Assembly, the following new items are required: (1) (includes Linkage Assembly, (2) Springs, (2) E-Clips, and (1) O-Ring (1) SEL - Vault Handle (if needed – we recommend replacing this also) IMPORTANT SAFETY MESSAGE: - Turn off power feeding Switch - Wear proper PPE - Use proper OSHA Safety Procedures while working on Switch 400A & 600A Heavy Duty Safety Switch Vault Handle and Linkage Replacement Instructions

1)Turn off power feeding switch. 2)Turn switch to OFF position. 3)Using screwdriver, release Vault Handle by turning screw in door below Vault Handle 4)Open Switch door 5)On door linkage assembly, remove C-clips and Springs from inside door handle mechanism. (discard old springs and C-clip C-clip Spring

2) On exterior of door, remove Vault Handle by pulling outward (If old handle is damaged, discard and use new handle. If old handle is not damaged, keep until later.) 3) Remove old Linkage Assembly and discard Vault Handle Linkage Assembly

4a) If using old handle, remove old O-ring and carefully install new O-ring into handle. 4b) If using new handle, carefully install new O-ring onto handle. 5) Install new Linkage Assembly onto door using new C-clips. 6) Carefully insert Vault Handle into hole in front of door and engage with Linkage Assembly. 7) Install new springs top and bottom. 8) Verify door closes and can be latched shut. 9) Verify that Vault Handle release screw on front of switch is able to release the handle. 10) Close switch door and latch it shut using Vault Handle 11) Energize switch using proper Safety Procedures.