MKS 109030111, Инструкция по эксплуатации

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6 Service & Maintenance
31
Series 903 Cold Cathode Vacuum Sensor
Instruction Manual - #109030026
6.4 Troubleshooting
6.5 Inspect and Clean the Sensor
If pressure readings appear to be erratic, the sensor tube may be contaminated. Inspect it visually. If
contamination is visible, replace the internal components with an Internal Rebuild Kit or a Rebuilt
Sensor. (see 6.6, Accessories and Spare Parts).
Depending on the degree of contamination and application of the IMT AP, The internal parts may
be cleaned - either ultrasonically, with mild abrasives, or chemically.
6.5.1 Disassembly
Tools required: clean tweezers and smooth-jaw, needle-nose pliers. Wear cleanroom gloves during
all handling and cleaning procedure.
See Figure 6-1 for disassembly and cleaning, and Figure 6-2 for final reassembly.
Table 6-1 General Symptoms/Possible Causes
Symptom Possible Causes Remedy
Pressure readings are too
erratic 1. Contaminated sensor 1. Inspect and clean if
necessary. See Section 6.?
No analog output voltage 1. D-sub is disconnected
2. Power supply turned OFF
3. Defective PC board 1. Connect D-sub
2. Turn power ON
3. Return to MKS for repair
Analog output voltage higher
than 7.7 V 1. High voltage is turned OFF See Section 4.3.1
Analog output voltage less
than 0.5 V 1. Discharge has not started
2. Pressure is less than 3 x10-
10
Torr
1. Wait for discharge to start or
increase pressure to speed up
starting time. Consider
purchasing an IgniTorr™.
2. Beyond range. Increase
pressure if desired
Analog output voltage
less
than 0.5 V and green LED OFF
1. No supply voltage.
2. Power supply turned OFF 1. Check cable connection.
2. Turn power ON.
Analog output voltage
less
than 0.5 V and green LED ON
1. Supply voltage too low. 1. Increase supply voltage to
provide 14 to 30 V at the
sensor.
Delicate Internal Components
Do not bend the anode (8) or the leaf spring (9) on the ion
current feed through pin (13) when disassembling or
assembling the Sensor; they are very fragile and could break.