Description of the individual safety relays
3.6 3TK28 safety relays with relay enabling circuits
3TK28 safety relays
Manual, 07/2016, NEB926157502000/RS-AB/003
105
3.6.9.5
Display of the operating state
The operating state and functioning of the device are indicated by five LEDs:
●
POWER
●
S 1 ON
●
S 2 ON
●
CHANNEL 1
●
CHANNEL 2
Operating states of 3TK2834
= off
= on
LED
Operation
POWER
S 1 ON
S 2 ON
Channel 1
Channel 2
Button
Not pressed
Only S1 pressed
Only S2 pressed
S1 and S2 pressed
The device cannot start with the following faults:
●
Short-circuit, e.g. between the buttons
●
Defective relay coils
●
Wire break
●
Jammed contacts
The output relays do not pick up if
●
simultaneity (< 0.5 s) is not achieved
●
only one button is pressed
●
feedback circuit Y11, Y12 is open.