GE 345 Communications Manual

CHAPTER 1: COMMUNICATIONS GUIDE USING THE MODBUS USER MAP
345 TRANSFORMER PROTECTION SYSTEM – COMMUNICATIONS GUIDE 1–179
Using the MODBUS User Map
345 relay units incorporate a powerful feature called Modbus User Map, that allows the
user to read 125 non-consecutive data records.
A master computer will often have to interrogate continuously several connected slave
relays. If the values being read are "randomly" positioned along the memory map, reading
them may require several transmissions, and this may cause a communications overload.
Data records that are positioned in this manner in the memory map, can be remapped to
the address of an adjacent record in the User Map area, so that they can be accessible to
the master computer with only a single read operation.
To program the map this way, addresses for the required records must be written in the
index area, which is located at the addresses from 40524 (0x020B) to 40648 (0x287).
Only single data from the Actual Values subset can be set in the map. The ranges of
addresses that can be configured in that index area are:
Range1 : 30001 to 30523 (Product Device Code to Internal Fault Cause)
[The address 30302 (Current Security Access Level) cannot be configured.]
Range2 : 30946 to 32036 (Alarm Status 4 to Last Actual Values Register)
The values that correspond to the points provisioned in the User Map index (40524
(0x020B) to 40648 (0x287)) may be read from the Actual Values map area located at the
addresses from 30524 (0x020B) to 30648 (0x0287).
MODBUS User Map
Table 42: User Map Settings
MODBUS
Address
Hex
Address
Description Min Max Step Format
Code
Factory
Default
40524 20B User Map Address 1 30001 43763 1 F1 30305
40525 20C User Map Address 2 30001 43763 1 F1 30505
40526 20D User Map Address 3 30001 43763 1 F1 30506
40527 20E User Map Address 4 30001 43763 1 F1 30960
40528 20F User Map Address 5 30001 43763 1 F1 30961
40529 210 User Map Address 6 30001 43763 1 F1 30958
40530 211 User Map Address 7 30001 43763 1 F1 30959
40531 212 User Map Address 8 30001 43763 1 F1 30956
40532 213 User Map Address 9 30001 43763 1 F1 30957
40533 214 User Map Address 10 30001 43763 1 F1 30954
40534 215 User Map Address 11 30001 43763 1 F1 30955
40535 216 User Map Address 12 30001 43763 1 F1 30952
40536 217 User Map Address 13 30001 43763 1 F1 30953
40537 218 User Map Address 14 30001 43763 1 F1 30950
40538 219 User Map Address 15 30001 43763 1 F1 30951
40539 21A User Map Address 16 30001 43763 1 F1 30948
40540 21B User Map Address 17 30001 43763 1 F1 30949
40541 21C User Map Address 18 30001 43763 1 F1 30946
40542 21D User Map Address 19 30001 43763 1 F1 30947
40543 21E User Map Address 20 30001 43763 1 F1 30976
40544 21F User Map Address 21 30001 43763 1 F1 30977
40545 220 User Map Address 22 30001 43763 1 F1 30974

GE 345 Specifications

General

Brand	GE
Model	345
Category	Relays
Language	English