22
Table 8.5: Relay Status Registers
Register 40030
The status of the Sigma relay’s output relay are bit mapped register 40030. The main trip relay
is mapped to Bit 0 which is 1 when the relay is tripped otherwise this bit is 0. The GND fault
relay is mapped to Bit 1 which is 1 when the relay is operated otherwise this bit is 0. The NGR
fault relay is mapped to Bit 2 which is 1 when the relay is operated otherwise this bit is 0
40030: 0000H or xxxx-xxxx-xxxx-0bbbB
X - don’t care
b - bit mapped relay status: 0 = all relays off
3 = main & gnd fault relays ON
5 = main & ngr fault relays ON
6 = main gnd fault & ngr fault relays ON
Register 40031
The status of each of the Sigma relay’s three red LEDs is mapped to individual hexadecimal digits in
MODBUS register 400031 as shown below.
40031: 0000H
0zng
hex. digit 0: g - gnd fault led status: 0 = OFF, 1 = ON, 2 = FLASHING
hex. digit 1: n - ngr fault led status: 0 = OFF, 1 = ON, 2 = FLASHING
hex. digit 2: z - zone led status: 0 = OFF, 1 = ON, 2 = FLASHING
hex. digit 3: always zero
nnnnH
four decimal digits
where n can b 0-9 or A-F
ddddB
four binary digits
where d can be 0 or 1
ddddddddB
eight binary digits
where d can be 0 or 1
Table 8.6: MODBUS Register Format Conventions
9. INSTALLATION
9.1 Sigma 3
9.9.1 Location
The Sigma monitor relay should be located as close as possible to the system’s isolating device, circuit breaker or
contactor.
9.1.2 Mounting
Mount the Sigma monitor relay horizontally using 35 mm DIN rail bolted or firmly fixed to flat surface. Allow at least 20
mm of rail to extend beyond each end of the relay.
