Alarm Relay
Original instructions
Description
The alarm relay located in each power supply module has a potential free contact accessible on a 2-pin removable terminal block:
Relay Alarm Operation
DANGER
LOSS OF ABILITY TO PERFORM SAFETY FUNCTIONS
Always use a redundant device when using the alarm relay in a functional safety application.
Failure to follow these instructions will result in death or serious injury.
Relay Status
Conditions
closed: The alarm relay is closed when all of these conditions are met.
24V_BAC is OK.
3V3_BAC is OK.
ALARM_CPU_N is high(1) or there is no CPU.
The RESET button is not activated.
open: The alarm relay is open when any of these conditions is met:
24V_BAC is not OK.
3V3_BAC is not OK.
ALARM_CPU_N is low.(2)
The RESET button is activated.
(1) No CPU blocking errors are detected and the PLC is in RUN mode. (2) A CPU blocking error is detected or the PLC is in STOP mode.
Alarm Relay Characteristics
Characteristic
Description
rated switching voltage/current
24 Vdc 2 A (resistive load)
240 Vac 2 A (cos Φ = 1) point
minimum switching load
5 Vdc 1 mA
maximum switching voltage
62.4 Vdc
264 Vac
contact type
normally open
contact time
OFF → ON: 10 ms or less
ON → OFF: 12 ms or less
built-in protection against overload or short circuits:
none
NOTE: Fit a fast-blow fuse.
built-in protection against inductive overvoltage in alternating current:
none
NOTE: Fit an RC circuit or a MOV [ZNO] suppressor that is appropriate to the voltage in parallel to the terminals of each pre-actuator.
built-in protection against inductive overvoltage in direct current:
none
NOTE: Fit a discharge diode to the terminals of each pre-actuator.
dielectric strength
contact vs. ground: 3000 Vrms, 50 Hz, 1 min.(altitude = 0…2000 m)
insulation resistance
100 ΜΩ or more under 500 Vdc
Alarm Relay Service Life
Electrical
Alternating current
200 Vac / 1.5 A
240 Vac / 1 A
cos Φ = 0.7
≥ 100,000 cycles
200 Vac / 0.4 A
240 Vac / 0.3 A
cos Φ = 0.7
≥ 300,000 cycles
200 Vac / 1 A
240 Vac / 0.5 A
cos Φ = 0.35
≥ 100,000 cycles
200 Vac / 0.3 A
240 Vac / 0.15 A
cos Φ = 0.35
≥ 300,000 cycles
Direct current
24 Vdc / 1 A
48 Vdc / 0.3 A
L/R = 7 ms
≥ 100,000 cycles
24 Vdc / 0.3 A
48 Vdc / 0.1 A
L/R = 7 ms
≥ 300,000 cycles
Mechanical
20 million cycles