Sel 751A - Table E.22 60 H Read Parameter Conversion Field Definition; Table E.23 Responses to 60 H Read Parameter Information Query Errors

E.16
SEL-751A Relay Instruction Manual Date Code 20100129
Modbus RTU Communications
Communications Protocol
The Parameter Conversion field is defined in Tabl e E.22.
Use Equation E.1 to calculate the actual (not scaled) value of the parameter
(setting):
Equation E.1
Use Equation E.2 to calculate the scaled setting value:
Equation E.2
The relay response to errors in the query are shown Table E.23.
4 RR: Read-only
if running
1 when the setting is read-only if in running/operational state
5 P: Power Cycle
or Reset
1 when the setting change requires a power cycle or reset
60 Reserved
7 Extend Reserved to extend the descriptor table
Table E.22 60h Read Parameter Conversion Field Definition
Conversion
Value
Type Multiplier Divisor Offset Base
0 Boolean 1 1 0 1
1 Unsigned Integer 1 1 0 1
2 Unsigned Integer 1 10 0 1
3 Unsigned Integer 1 100 0 1
4 Unsigned Integer 1 1000 0 1
5 Hexidecimal 1 1 0 1
6Integer 1101
7 Integer 1 10 0 1
8 Integer 1 100 0 1
9 Integer 1 1000 0 1
10 Enumeration 1 1 0 1
11 Bit Enumeration 1 1 0 1
Table E.23 Responses to 60h Read Parameter Information Query Errors
Error Error Code Returned
Communication
Counter Increments
Illegal parameter to read Illegal Address (02h) Invalid Address
Table E.21 60h Read Parameter Descriptor Field Definition (Sheet 2 of 2)
Bit Name Description
value
ParameterValue Offset+()Multiplier Base• •
Divisor
----------------------------------------------------------------------------------------------------------------------------=
value
value Divisor•
Multiplier Base•
---------------------------------------------- O f f s e t–=