Reading Of One Register; Reading Of Two Registers - ABB Relion 620 Series Protocol Manual

Section 3
Vendor-specific implementation
3.5.3.1
3.5.3.2
66
The SPA data type and number define the value response format.

Reading of one register

The examples below are from reading the register 138. The SPA slave number is 25.
The actual value in register 138 is assumed to be 52342 (decimal). It does not matter
from SPA point of view if the register value is formed from one measurand or if it is
a register packed with indication bits. The SPA stack does not know the origin of the
register value. The system engineer selects the most appropriate read method.
(I1/16) Read the register as separate SPA bits:
>25R138I1/16:CC
<25D:1/0/0/1/1/1/1/0/0/0/1/1/0/0/1/1:CC
(I30) Read the register as one signed 16 bit decimal value:
>25R138I30:CC
<25D:-13193:CC
(I31) Read the register as one unsigned 16 bit decimal value:
>25R138I31:CC
<25D:52342:CC
(I32) Read the register as one 16 bit hexadecimal value:
>25R138I32:CC
<25D:CC76:CC
It is also possible to read several consecutive 16 bit registers in one SPA read message.
The register values are all in the same format. For example:
>25R138/140I32:CC
<25D:CC76/C845/C772:CC

Reading of two registers

Since some Modbus analog values can reside in two consecutive register pairs, it is
possible to read these values in one read message. For example, registers 146 and 147
could contain one 32 bit value (0xF025A476). The read message should always be
directed to the first register address of the register pair.
(I40) Reading the registers as one 32 bit signed decimal value:
>25R146I40:CC
<25D:-265968522:CC
(I41) Reading the registers as one 32 bit unsigned decimal value:
>25R146I41:CC
<25D:4028998774:CC
(I42) Reading the registers as one 32 bit hexadecimal value:
1MRS757645 B
620 series
Communication Protocol Manual