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1–4
345 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
DESCRIPTION OF THE 345 TRANSFORMER PROTECTION SYSTEM
CHAPTER 1: INTRODUCTION
Figure 2: Single line diagram
897743.CDR
345
REL
A
Y
50G/
51G
50G/
51G
Metering
Calculate
Restraint Current
Calculate
Differential Currents
Calculate
Harmonics
2nd and 5th
BLOCK
50P
50P
50G
50G
51P
51P
51G
51G
50BF
50BF
51_2
51_2
50
N
50
N
51
N
51
N
87G
87G
87T
50/87
Winding 2
Winding 1
49P