S&C PMH-3 - 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

S&C PMH-3 Specifications

General

Continuous Current	600 A
Frequency	60 Hz
Interrupting Rating	12.5 kA
BIL	95 kV
Type	Pad-Mounted
Rated Voltage	15 kV
Rated Interrupting Current	12.5 kA
BIL Rating	95 kV
Operating Mechanism	Manual

Summary

Safety Information

Understanding Safety-Alert Messages

Explains signal words (DANGER, WARNING, CAUTION, NOTICE) and their associated hazard levels.

Safety Precautions

Personnel and Procedure Requirements

Access, procedures, PPE, and label adherence for safe operation.

Electrical Safety and Grounding

Warnings on energized parts, backfeed, testing, and grounding procedures.

Enclosure Doors

Opening and Closing Procedures

Step-by-step instructions for opening and closing the enclosure doors.

Switching with Mini-Rupter Switches

Operating the Mini-Rupter Switch

Instructions for operating the Mini-Rupter switch, including handle use and position checks.

Switching with Mini-Rupter Switches - Barriers

Front Barrier Installation and Handling

Guidance on inserting dual-purpose front barriers using a Grappler Handling Tool.

Fusing

Fuse Assembly and Installation

Instructions for assembling S&C Power Fuses and current-limiting fuses.

Switching with Uni-Rupter Interrupters

Installing and Closing the Fuse

Detailed steps for installing and closing fuses using specialized handling tools.

Switching with Uni-Rupter Interrupters - Fuse Installation

Fuse Installation Steps

Specific procedures for installing S&C Power Fuses and Fault Fiter Electronic Power Fuses.

Switching with Uni-Rupter Interrupters - Fuse Removal

Opening and Removing the Fuse

Step-by-step instructions for safely opening and removing fuses.

Re-Fusing

Detecting and Replacing Blown Fuses

Methods to identify blown fuses and procedures for replacement.

Maintenance

Gear Components and Inspections

Returning Equipment to Service

Appendix D

Current-Limiting Fuses and Holders