GE Multilin 565 Instruction Manual Download

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FEATURE INFORMATION

6-8

Message Format and Example (numbers are expressed in
HEX)

Request slave 11 to respond with 3 setpoints starting at
address 006B. For this example the setpoints data in these
addresses is:
Address

Data

006B

022B

006C

0000

006D

0064

Master Transmission:

HI LO

00 6B

00 03

?? ??

ADDRESS FUNCTION

START

SETPOINT

CRC

CODE

ADDRESS

COUNT

Slave Response:

HI LO

02 2B

00 00

00 64

?? ??

ADDRESS FUNCTION

BYTE

DATA

CRC

CODE

COUNT

FUNCTION CODE 04
Modbus Implementation: Read Input Registers
565 Feeder Management Relay Implementation: Read Ac-
tual Values
This function code allows the master to read a group of
actual values from a slave device. The maximum number of
input registers that can be read in one transmission is 125.
Number of input registers should match the total length of
required actual values. In other words, reading half of an
actual value is not recommended. For the 565 Feeder Man-
agement Relay implementation of Modbus, “input registers”
are equivalent to 565 Feeder Management Relay actual
values. Input registers are 16 bit (two byte) values transmit-
ted high order byte first. But all 565 Feeder Management
Relay actual values are not made of two bytes. Some of them
are four bytes long and in that case two consecutive input
register addresses are used to transmit data of one actual
value. Input register with lower address number carries two
more significant bytes.

The slave response to this function code is the slave ad-
dress, function code, a count of the number of data bytes to
follow, the data itself, and the CRC. Each data item (actual
value) is sent as a two byte number with the high order byte
sent first.

Note: Broadcast mode is not allowed with this function code.
The master transmission will be ignored by all slaves if
broadcast mode is used with this function code.

Message Format and Example

Request slave 11 to respond with 1 actual value starting at
address 0008. For this example the actual value in this
address (0008) is 0000.

Master Transmission:

HI LO

00 08

00 01

?? ??

ADDRESS FUNCTION

START

ACT. VAL.

CRC

CODE

ADDRESS

COUNT

Slave Response:

HI LO

00 00

?? ??

ADDRESS FUNCTION

BYTE

DATA

CRC

CODE

COUNT

FUNCTION CODE 05
Modbus Implementation: Force Single Coil
565 Feeder Management Relay Implementation: Execute
Operation
This function code allows the master to request the 565
Feeder Management Relay to perform specific operations.
The operations that can be performed by the 565 Feeder
Management Relay are as follows:
Operation Code Function
00

Reset (keypad)

End of Relay Test

End of LED Test

End of Analog Output Test

Test LCD Display

Test LEDs

0FH

Clear Maintenance Data

10H

Clear Operations Data

11H

Clear Amp Demand Data

12H

Clear KW Demand Data

13H

Clear KVAR Demand Data

14H

Clear Events

Note: Broadcast mode is allowed with this function code.
When a broadcast transmission is sent by the master (ie.
SLAVE ADDRESS = 0) the selected operation will be ex-
ecuted by all slave devices on the communication link. No
response will be sent from any of the slaves.

Message Format and Example

Request slave 11 to execute operation code 1.

Master Transmission:

HI LO

00 01

FF 00

?? ??

ADDRESS FUNCTION OPERATION CODE

CRC

CODE

VALUE

(Perform Function)