Description of the individual safety relays
3.6 3TK28 safety relays with relay enabling circuits
3TK28 safety relays
74
Manual, 07/2016, NEB926157502000/RS-AB/003
3.6.6.6
Display of the operating state
The operating state and functioning of the device are indicated by three LEDs:
●
POWER
●
CHANNEL 1
●
CHANNEL 2
Operating states of 3TK2825
= off
= on
LED
Operation
POWER
CHANNEL 1
CHANNEL 2
Line supply
EMERGENCY
STOP
ON
Enabling circuit
On
Not pressed
Pressed
Closed
Pressed
Not pressed
Open
Not pressed
Not pressed
Open
Fault
•
Relay welded
•
Motor contactor welded
•
Fault in electronics
•
Short-circuit in ON circuit
Open
Cross-circuit in EMERGENCY STOP circuit
(minimum fault current I
Kmin
= 0.5 A; PTC fuse
responds)