2–30
745 TRANSFORMER PROTECTION SYSTEM – COMMUNICATIONS GUIDE
MODBUS PROTOCOL
CHAPTER 2: MODBUS PROTOCOL
Harmonic derating
0430
Winding 1 harmonic derating factor
0.00 to 1.00
0.01
---
F3
---
0431
Winding 2 harmonic derating factor
0.00 to 1.00
0.01
---
F3
---
0432
Winding 3 harmonic derating factor
0.00 to 1.00
0.01
---
F3
---
0433
Reserved
0434
Reserved
↓
↓
↓
↓
↓
↓
↓
043F
Reserved
Frequency
0440
System Frequency
0.00 to 99.99
0.01
Hz
F3
---
0441
Frequency Decay Rate
–9.99 to 9.99
0.01
Hz/s
F6
---
0442
Reserved
0443
Reserved
0444
Reserved
Tap changer
0445
Tap changer position
1 to 50
1
---
F1
---
0446
Reserved
0447
Reserved
0448
Reserved
Voltage
0449
System line-to-line voltage
0.00 to 600.00
0.01
kV
F3
---
044A
Volts-per-hertz
0.00 to 4.00
0.01
V/Hz
F3
---
044B
Line-to-neutral voltage magnitude
0.00 to 600.00
0.01
kV
F3
---
044C
Line-to-neutral voltage angle
0 to 359
1
° Lag
F1
044D
Reserved
044E
Reserved
044F
Reserved
Current demand
0450
Demand data last clear date (2 registers)
---
---
---
F23
---
0452
Demand data last clear time (2 registers)
---
---
---
F22
---
0454
Winding 1 phase A current demand
---
---
A
F78
---
0455
Winding 1 phase B current demand
---
---
A
F78
---
0456
Winding 1 phase C current demand
---
---
A
F78
---
0457
Winding 1 maximum current demand
---
---
A
F78
0 A
0458
Winding 1 maximum current demand phase
---
---
---
F18
0 = phase A
0459
Winding 1 maximum current demand date (2 registers)
---
---
---
F23
Jan 01 1996
045B
Winding 1 maximum current demand time (2 registers)
---
---
---
F22
00:00:00.000
045D
Winding 2 phase A current demand
---
---
A
F79
---
045E
Winding 2 phase B current demand
---
---
A
F79
---
045F
Winding 2 phase C current demand
---
---
A
F79
---
0460
Winding 2 maximum current demand
---
---
A
F79
0 A
0461
Winding 2 maximum current demand phase
---
---
---
F18
0 = phase A
0462
Winding 2 maximum current demand date (2 registers)
---
---
---
F23
Jan 01 1996
0464
Winding 2 maximum current demand time (2 registers)
---
---
---
F22
00:00:00.000
0466
Winding 3 phase A current demand
---
---
A
F80
---
0467
Winding 3 phase B current demand
---
---
A
F80
---
0468
Winding 3 phase C current demand
---
---
A
F80
---
Table 2–4: 745 memory map (Sheet 18 of 56)
Addr
Description
Range
Step
Units
Format
Default