LEYBOLD IONIVAC ITR 90, Руководство по эксплуатации

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Maintenance, Repair
40
GA09420_002_C0 – (2016-10) – 
Leybold
Problem Possible cause Correction
Output signal
permanently
≈
0V
Sensor cable defective or
not correctly connected Check the sensor cable
No supply voltage Turn on the power supply
transmitter in an unde-
fined status Turn the transmitter off
and on again (reset)
Output signal
≈
0.3 V
Display: "FAIL 8"
Hot cathode error
(sensor faulty) Replace the sensor
(
→  41)
Output signal ≈ 0.5 V
Display: "FAIL 9"
Pirani error
(sensor defective) Replace the sensor
(
→
 41)
Electronics unit not
mounted correctly on
sensor Check the connection the
electronics unit - sensor
Display: Internal data connection
not working
Turn the transmitter off
and on again after 5 s
Replace the electronics
unit
transmitter does not
switch over to BA at low
pressures Pirani zero point out of
tolerance Carry out a zero point
adjustment (
→
 39)
Troubleshooting (sensor)
If the cause of a fault is suspected to be in the sensor, the following checks can be
made with an ohmmeter (the vacuum system need not be vented for this purpose).
Separate the sensor from the electronics unit (
→
 14). Using an ohmmeter, make
the following measurements.
Ohmmeter measure-
ment between pins Possible cause
2 + 4
≈ 37 Ω >>37 Ω Pirani element 1 broken
4 + 5
≈ 37 Ω >>37 Ω Pirani element 2 broken
6 + 7
≈ 0.15 Ω >>0.15 Ω
Filament of hot cathode broken
4 + 1 ∞
<<
∞ Electrode - short circuit to ground
6 + 1 ∞
<<
∞ Electrode - short circuit to ground
3 + 1 ∞
<<
∞ Electrode - short circuit to ground
9 + 1 ∞
<<
∞ Electrode - short circuit to ground
6 + 3 ∞
<<
∞ Short circuit between electrodes
9 + 3 ∞
<<
∞ Short circuit between electrodes