METRON QA-1290 - Testing and Maintenance; Required Equipment; Testing Procedures

6. Testing and Maintenance
This chapter covers QA-1290 testing, as well as maintenance and
troubleshooting procedures.
6.1 Required Equipment
• Digital voltmeter, e.g. Fluke 87
• Pressure instrument, e.g. Drück DPI-601
6.2 Testing Procedures
1. Power Supply
• Connect +5.0 v and +24.0 v on P300.
• Measure the following voltages are referenced to ground on
T307.
Reference Nominal value
T300 - T307
+24.0 V ± 7%
T306 - T307
+5.0 V ± 5%
T301 - T307
+15.0 V ± 5%
T302 - T307
+12.0 V ± 5%
T303 - T307
-12.0 V ± 5%
T304 - T307
+5.0 V ± 5%
T305 - T307
-5.0 V ± 5%
2. Analog Ground. Verify that the analog and digital grounds on
T307 – T150are tied together. The nominal value is 0 Ω + 0.1 Ω.
3. Reference Voltages. Inspect the following voltages referenced
to ground on T150. Nominal values are as follows:
Reference Nominal value
T153 - T150
+5.0v ± 5%
T154 - T150
+12.1v ± 5%
T155 - T150
-1.2v ± 5%
4. A/D converter
• Measure the frequency of the oscillator on the A/D con-
verter on T156. The nominal value is 4 MHz ± 20 kHz.
• Check the amplitude on the oscillator on T156. The nominal
value is 5.0V ± 0.5V.
5. Functional QA-1290 System Test
• Connect signal- and power cables to front board, step motor,
compressor and valve. Turn on the power.
• Verify in display that system runs and that SW starts.
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