Modbus User Map - GE 350 Communications Manual

GE
Digital Energy
SR350 Feeder Protection System
Chapter 10: Using the MODBUS User
Map

MODBUS User Map

350 FEEDER PROTECTION SYSTEM – COMMUNICATIONS GUIDE
Using the MODBUS User Map
350 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).
Table 10-1: User Map Settings
MODBUS Hex Description
Address Addres
s
40524 20B User Map Address 1
40525 20C User Map Address 2
40526 20D User Map Address 3
40527 20E User Map Address 4
40528 20F User Map Address 5
40529 210 User Map Address 6
40530 211 User Map Address 7
Min Max Step
30001 43763 1
30001 43763 1
30001 43763 1
30001 43763 1
30001 43763 1
30001 43763 1
30001 43763 1
Format Factory
Code Default
F1 30305
F1 30505
F1 30506
F1 30960
F1 30961
F1 30958
F1 30959
10–1