If The Red Led Of The A15 Is On - Agilent Technologies 8753ES Option 011 Service Manual

Power Supply Troubleshooting

If the Red LED of the A15 Is ON

If the Red LED of the A15 Is ON
If the red LED is on or flashing, the power supply is shutting down. Use the following
procedures to determine which assembly is causing the problem.
Check the A8 Post Regulator
1. Switch off the analyzer.
2. Disconnect the cable A15W1 from the A8 post regulator. (See
3. Switch on the analyzer and observe the red LED on A15.
• If the red LED goes out, the problem is probably the A8 post regulator. Continue to
"Verify the A15 Preregulator" on page 5-10
correct.
• If the red LED is still on, fuse F4 in the preregulator A15 may need to be replaced if
the line voltage selector switch was set to 120 V, and the instrument was connected
to a 220 V supply.
• If the red LED is still on, the problem is probably the A15 preregulator, or one of the
assemblies obtaining power from it. Continue with
page 5-11.
5-8
Figure
to first verify that the inputs to A8 are
"Check for a Faulty Assembly" on
5-5.)
Chapter 5