
121022 v1.02-RiA
Operating instructions SG-RS 309-2
Page 20/23
Troubleshooting and remedies
Fault indication
Possible cause
Remedy
Yellow “S1” LED and red
“F” LED are flashing
Sensor not connected (or not connect-
ed correctly) to terminals Y1 and Y2
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Connect sensor
Sensor 1 cable break
1. Measure resistance at sensor 1: target
value = 8k2 ±5% or 10k ±5%
2. Actual value > 1M: sensor is faulty
3. Replace sensor
4. Disconnect power supply for at least
500 ms
Yellow “S2” LED and red
“F” LED are flashing
Sensor not connected (or not connect-
ed correctly) to terminals Y3 and Y4
Ä
Connect sensor
Sensor 2 cable break
1. Measure resistance at sensor 2: target
value = 8k2 ±1% or 10k ±1%
2. Actual value > 1M: sensor is faulty
3. Replace sensor
4. Disconnect power supply for at least
500 ms
Green “P”, yellow “S1”
and/or yellow “S2” LEDs
are lit up
Automatic
reset: bridges missing
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Place bridges between S13 and S15 as
well as between S14 and S15
Controlled
reset: no reset signal from
higher-level control or pulse duration
is too short
Ä
Trigger a signal pulse from the control
system (≥ 70 ms)
Controlled reset: connection to control
interrupted
Ä
Check connection
Manual
reset: reset button not
pressed or not held down long
enough
Ä
Press reset button (≥ 70 ms)
Manual reset: connection to reset but-
ton interrupted
Ä
Check connection
Control unit is faulty
Ä
Replace control unit
Green “P”, yellow “S1”
and yellow “S2” LEDs
are lit up, red “F” LED
flashes
Controlled or manual reset: duration
of signal pulse from higher-level
control is too long or reset button is
jammed
1. Check the duration of the signal pulse
(≤ 19 s) from the higher-level control
or replace the reset button at S13 and
S14
2. Disconnect power supply for at least
500 ms
Control unit is faulty
Ä
Replace control unit
Still unable to resolve the fault?
Ä
Contact Mayser-Support: Tel. +49 731 2061-0.
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In the event of enquiries, have the information from the type plate to hand.
Type plate
There is a type plate on the side of the control unit for identification purposes.