Associated Hardware
Emergency Transfer Units
General
The emergency transfer units used with the 66-type/110-type hardware
are the Z1A emergency transfer unit and the 574-5 power transfer unit.
The units mount on the plywood backboard to the left of the
trunk/auxiliary field.
Z1A Emergency Transfer Unit
The Z1A emergency transfer unit provides emergency transfer
connections for six telephones. If the central office (CO) trunks require
ground start, a ground start key must be installed on each emergency
transfer telephone.
574-5 Power Transfer Unit
The 574-5 power transfer unit (Figure 2-19) provides power transfer
connections for five telephones. This unit provides automatic ground
start.
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Summary of Contents for System 75
Page 1: ...AT T AT T System 75 and System 75 XE Wiring...
Page 2: ...AT T AT T System 75 and System 75 XE Wiring 555 200 111 Issue 2 August 1989...
Page 16: ...System Wiring Figure 1 2 System Uniform Wiring Plan 1 7...
Page 17: ...CHAPTER 1 INTRODUCTION Figure 1 3 Sample Uniform Wiring Installation 1 8...
Page 29: ...CHAPTER 2 HARDWARE 66 110 Type Figure 2 1 Block Diagram of System 75 or 75 XE Installation 2 2...
Page 35: ...CHAPTER 2 HARDWARE 66 110 Type Figure 2 4 110A Type 100 Pair Terminal Block 2 8...
Page 36: ...110 Type Hardware Description Figure 2 5 110A Type 300 Pair Terminal Block 2 9...
Page 98: ...Typical System Equipment Room Floor Plans 3 15...
Page 143: ...CHAPTER 3 EQUIPMENT ROOM DESIGN 3 60...
Page 144: ...Equipment Room Hardware And Cabling Installation 3 61...
Page 162: ...Equipment Room Hardware And Cabling Installation 3 79...
Page 163: ...Equipment Room Hardware And Cabling Installation 3 80...
Page 197: ...Tables Table 4 A Recommended Protectors 4 42 v...
Page 212: ...Adjunct Powering 4 15...
Page 214: ...Adjunct Powering 4 17...
Page 216: ...Patch Cord Jumper Installation And Administration 4 19...
Page 241: ...CHAPTER 4 STATION WIRING 4 44...
Page 244: ...Miscellaneous Wiring Installation 4 47...
Page 246: ...Miscellaneous Wiring Installation 4 49...
Page 252: ...Miscellaneous Wiring Installation 4 55...
Page 254: ...Miscellaneous Wiring Installation 4 57...
Page 314: ...CHAPTER 5 AUXILIARY EQUIPMENT INSTALLATION 5 41...
Page 324: ...CHAPTER 5 AUXILIARY EQUIPMENT INSTALLATION 5 51...