LEYBOLD THERMOVAC TTR 101 N, Operating Manual, Page: 35 / 42

35 300544655_002_C1 - 11/2016 - © Leybold
Trouble shooting
Symptom Possible Cause/Remedy
No digital communication - Check electrical connections (3 wires from transmitter to
communication equipment)
- Transmitter and communication equipment baud rates have
to match
- Use of incorrect transmitter address. Try address 254
- Attention characters missing (@)
- Termination characters missing (;FF)
NAK180 is received when
transmitting setpoint commands
- The transmitter setup is locked. Refer to disable lock
procedure in the communication protocol.
Incorrect pressure value - Other gas present than transmitter gas setting or trace of
gas.
- Contaminated sensor. Transmitter repair required.
- Corroded sensor. Transmitter repair required.
- Perform a zero adjustment/FS adjustment.
- Check Setting of Controller or display.
Incorrect pressure value at low
pressure - Contaminated sensor. Transmitter repair required.
- Corroded sensor. Transmitter repair required.
- Incorrect zero adjustment has been executed.
- Transmitter exposed to heat or cooling air stream.
- Perform a zero adjustment.
Incorrect pressure value at high
pressure. - Contaminated sensor. Transmitter repair required.
- Corroded sensor. Transmitter repair required.
- Incorrect FS adjustment has been executed.
- Other gas or gas trace present than transmitter gas setting.
- Perform a FS adjustment.
Set point relay does not trip - Setpoint not enabled.
- Setpoint value not set to proper value.
- Setpoint direction is different than the user expects.
- Check electrical connection.
- Check part number to see if transmitter has setpoint relays.
No analog output - Power supply turned off.
- Check electrical connections.
Status light ring illuminating red - Sensor element defect.