S&C PMH-12 - User Manual

Manual PMH Pad- Mounted Gear
Outdoor Distribution (14.4 kV and 25 kV)
December 9, 2019
© S&C Electric Company 1978-2019, all rights reserved
Instruction Sheet 662-510
Operation
Table of Contents
Section Page Section Page
Introduction
Qualified Persons ........................... 2
Read this Instruction Sheet ................... 2
Retain this Instruction Sheet. . . . . . . . . . . . . . . . . . . 2
Proper Application .......................... 2
Warranty .................................. 2
Warranty Qualifications ...................... 3
Safety Information
Understanding Safety-Alert Messages ........... 4
Following Safety Instructions .................. 4
Replacement Instructions and Labels ........... 4
Location of Safety Labels ..................... 5
Safety Precautions ......................... 7
Overview ................................... 8
Enclosure Doors
Opening and Closing the Doors ................10
Switching with Mini-Rupter® Switches
Operating the Mini-Rupter Switch ..............12
Front Barriers ..............................13
Fusing
Assembling the Fuse ........................15
Installing the Fuse in the Mounting ..............15
Switching with Uni-Rupter® Interrupters
Installing and Closing the Fuse ................16
A Note on Single-Pole Switching ...............19
Opening and Removing the Fuse .............. 20
Re-Fusing
How to Detect and Replace a Blown Fuse ....... 23
Installing the Fuse in the Mounting ............. 23
Maintenance
Components .............................. 24
Returning Equipment to Service ............... 24
Enclosure Finish ........................... 25
Appendix A
Dielectric Testing .......................... 26
Appendix B
Ratings for S&C Mini-Rupter Switches .......... 27
Ratings for S&C Power Fuses with
Uni-Rupter Interrupters ................... 27
Appendix C
Optional Features .......................... 28
Appendix D
Current-Limiting Fuses for Use in
S&C PMH Pad-Mounted Gear .............. 31
Recommended Voltage Ratings ............... 32

Summary

Introduction

Qualified Persons

Only qualified persons knowledgeable in installation, operation, and maintenance of electrical distribution equipment may install or operate.

Safety Information

Understanding Safety-Alert Messages

Familiarize yourself with safety-alert messages and the importance of signal words like DANGER, WARNING, CAUTION, and NOTICE.

Following Safety Instructions

Contact S&C Sales Office or Authorized Distributor if any portion of this instruction sheet is not understood.

Location of Safety Labels

Safety Precautions

Switching with Mini-Rupter Switches

Operating the Mini-Rupter Switch

Detailed steps for safely operating the Mini-Rupter Switch, including handle use and position verification.

Fusing

Assembling the Fuse

Switching with Uni-Rupter Interrupters

Installing and Closing the Fuse

Step-by-step guide for safely installing and closing fuses using a Grappler Handling Tool and universal pole.

Opening and Removing the Fuse

Detailed steps for safely opening and removing fuses from Uni-Rupter Interrupters using specific tools.

Re-Fusing

How to Detect and Replace a Blown Fuse

Methods to visually check for blown fuses using targets on SML-4Z and SML-20/Fault Fiter fuses.

Installing the Fuse in the Mounting

S&C PMH-12 Specifications