31
‡
8. Failure signal
If necessary, the failure signal (terminals K1.1 and
K1.2) can be used to analyze valve function. The fai-
lure signal is activated if the positioner is not able to
comply the actual value (stroke) with the set
value (control signal); for example if there is no or
too low supply air pressure. In this case, the LED on
the connector board lights up.
Direct circuit:
Us = signal voltage
No failure function: low signal
Failure function: 0.5 Hz impulse
max. working voltage: U
B,max
=24 V DC
external load R:
e.g. 470
Ω
max. signal current:
I
s,max
= 50 mA
Relay (recovery diode for inductive loads!)
9. Troubleshooting
Problem
Possible causes
Controller fails/
– Connected incorrectly
does not work
(electr. and pneum.)
– Operating error
– Control pressure too
high
– Electronics defective
– Sensor defective
– Transport damage
!
