Nortel DMS-100 Series User manual

Applies to all BCS and PCL levels Standard 02.02 August 1997
297-1001–350
DMS-100 Family
Digital Switching Systems
Power and Grounding Routine Maintenance
Manual

DMS-100 Family Power and Grounding Routine Maintenance Manual Applies to all BCS/PCL levels
Digital Switching Systems
DMS-100 Family
Power and Grounding Routine Maintenance Manual
1988, 1989, 19941997 Northern Telecom
All rights reserved.
Printed in Canada and printed in the United States of America.
NORTHERN TELECOM CONFIDENTIAL: The information contained in this document is the property of Northern
Telecom. Except as specifically authorized in writing by Northern Telecom, the holder of this document shall keep the
information contained herein confidential and shall protect same in whole or in part from disclosure and dissemination to third
parties and use same for evaluation, operation, and maintenance purposes only.
Information is subject to change without notice. Northern Telecom reserves the right to make changes in design or components
as progress in engineering and manufacturing may warrant.
DMS
, DMS-100, NT, are trademarks of Northern Telecom. DIGISNAP is a trademark of the A. W. Sperry Instruments, Inc. HP
is a trademark of the Hewlett-Packard Co.
Publication number: 297-1001-350
Product release: Applies to all BCS/PCL levels
Document release: Standard 02.02
Date: August 1997

DMS-100 Family Power and Grounding Routine Maintenance Manual Applies to all BCS/PCL levels
iii
Publication history
August 1997 Standard 02.02 was issued to incorporate editiorial markup and customer
feedback.
June 1994 Standard 02.01 was issued for the following reasons:
•to compose NTP 297-1001-350 in a new typographical style
(restructured format).
•to comply with the generic design intent, terminology, and definitions
of applicable Northern Telecom Corporate Standards and NTP
297-1001-156, DMS-100 Family Power Distribution and Grounding
Guide
•to improve the composition, arrangement, and structure of the content
•to simplify and improve the text, figures, and tables.
March 1989 Standard 01.04 was issued for technical corrections and replaced all
previous releases.

DMS-100 Family Power and Grounding Routine Maintenance Manual Applies to all BCS/PCL levels
Draft: June 2, 1993
v
Contents
About this document ix
Application of this document ix
References ix
Prerequisite references x
Informative references x
1 Introduction 1–1
1.1 Definitions 1–1
battery return (BR): 1–1
battery return reference (BRR): 1–1
bonding: 1–1
bonding network (BN): 1–1
building principal ground (BPG): 1–1
common bonding network (CBN): 1–1
DMS-100 Family: 1–2
DMS single point ground (DMS SPG): 1–2
floor ground bar (FGB): 1–2
framework bonding bar (FBB): 1–2
framework bonding equalizer (FBE) bar: 1–2
framework ground bus: 1–2
ground: 1–3
incidental ground: 1–3
isolated bonding network (IBN): 1–3
isolated system grounding (ISG): 1–3
isolation: 1–3
logic return bar (LRB): 1–3
logic return equalizer (LRE) bar: 1–3
single point ground (SPG): 1–4
vertical ground riser (VGR): 1–4
vertical logic return bar: 1–4
1.2 Abbreviations and acronyms 1–4
1.3 Cross reference of terms 1–6
2 Overview 2–1
2.1 DC power 2–1
2.2 AC power 2–1
2.3 Grounding 2–1
3 Power system maintenance 3–1
3.1 Preparations 3–1

vi Contents
297-1001-350 Standard 02.02 August 1997
Draft: June 2, 1993
3.1.1 Maintenance records 3–1
3.1.2 Maintenance action record 3–17
3.1.3 Tools 3–17
3.2 Power plant critical limits 3–18
3.3 Power plant maintenance schedule 3–19
3.4 Power plant checks 3–20
3.5 Power plant safety checks 3–21
3.6 Power plant fuse checks 3–22
3.7 Charging equipment checks 3–22
3.8 Battery equipment checks 3–24
3.8.1 Maintenance intervals 3–24
3.8.2 Trouble conditions 3–26
3.8.3 Post connections 3–26
3.8.4 Positive plate growth 3–26
3.8.5 Post corrosion 3–27
3.8.6 Electrolyte level and temperature 3–32
3.8.7 Water analysis report 3–32
3.8.8 Avoiding battery trouble 3–33
3.9 Standby power system checks 3–34
3.10 Standby engine-alternator checks 3–35
3.11 Standby power system exercise 3–36
3.11.1 Precautions 3–36
3.11.2 Preparations 3–37
3.11.3 Procedure 3–38
3.12 Miscellaneous power plant checks 3–41
3.13 Submitting the maintenance report 3–42
4 Grounding system maintenance 4–1
4.1 Grounding system diagrams 4–1
4.2 Tools required 4–1
4.3 Building principal ground (BPG) checks 4–2
4.4 Ground resistance test 4–3
4.5 Floor ground bar (FGB) checks 4–3
4.6 Power plant grounding checks 4–4
4.7 AC grounding checks 4–4
4.7.1 AC-free DMS switch 4–4
4.7.2 Other DMS switch versions 4–5
4.8 DMS SPG checks 4–5
4.9 Framework bonding equalizer (FBE) checks 4–6
4.10 Framework ground bus checks 4–7
4.11 Logic return equalizer (LRE) checks 4–8
4.12 Logic return bar (LRB) checks 4–9
4.13 Bonding within DMS cabinets/frames 4–9
4.14 Cable entrance ground bar (CEGB) checks 4–9
4.15 Main distribution frame/protector frame checks 4–10
4.16 Cleaning corroded grounding connections 4–11
4.17 Grounding audit 4–12
List of figures
Figure 3–1 Sample pilot cell voltage and specific gravity test record 3–3

Contents vii
DMS-100 Family Power and Grounding Routine Maintenance Manual Applies to all BCS/PCL levels
Draft: June 2, 1993
Figure 3–2 Sample battery electrical and specific gravity measurements
record 3–4
Figure 3–3 Sample charging plant capacity and reserves data record 3–5
Figure 3–4 Sample telephone number record 3–6
Figure 3–5 Standby engines—office loads and battery reserves record 3–7
Figure 3–6 Sample power plant alarm check record 3–8
Figure 3–7 Sample log sheet for stationary alternator routine engine runs
3–9
Figure 3–8 Sample log sheet for mobile alternator routine engine runs
3–10
Figure 3–9 Sample standby power system exercise evaluation report 3–11
Figure 3–10 Standby power system exercise control log 3–12
Figure 3–11 Standby power system exercise—stationary engine-alternator
log 3–13
Figure 3–12 Standby power system exercise—mobile engine-alternator log
3–14
Figure 3–13 Battery load test record 3–15
Figure 3–14 Power plant maintenance action required 3–16
Figure 3–15 Typical internal parts of a battery 3–29
Figure 3–16 Positive plate growth 3–30
Figure 3–17 Battery post and intercell connector corrosion 3–31
List of tables
Table 1–1 Cross reference of terms 1–6
Table 3–1 Power plant maintenance schedule 3–19
Table 3–2 Power plant data, monitored conditions 3–23
Table 3–3 Schedule of battery readings and work intervals 3–25
Table 3–4 Maximum allowable impurities in battery water 3–33
Table 3–5 Recommended battery load test duration 3–40