Teledyne 401 Model Vehicle User Manual


 
Teledyne API Model 401 O
3
Photometric Calibrator Instruction Manual, 01124, Rev. J2
9.2.2 Checking The CPU And Display
When the analyzer is turned on, the front panel display should energize and the green "Sample"
LED should light. If proper DC power is present (see Section 9.2.1), the absence of these actions
will usually indicate either a CPU or Display failure. To determine which module is defective,
perform the following procedure:
1. Turn off power.
2. Remove the ribbon cable from the CPU board to the Display;
3. Turn Power on.
4. A cursor character should appear in the upper left corner of the display. If it does not, the
display is defective and should be replaced. If the cursor does appear, it is probable that the
CPU is faulty.
9.2.3 Checking The Keyboard
During normal Calibrator operation, depressing the right most key of the keyboard should cause
a change of display modes. If it does not, check:
1. Cable connections.
2. CPU and Display operation (see Section 9.2.2).
If these checks are satisfactory, it is probable that the keyboard is defective and should be
replaced.
9.3 Troubleshooting Using Warning Messages
The most common and/or serious instrument failures will result in a warning message (or
messages) being displayed on the front panel. Table 9-1 lists the warning messages which the
Calibrator may display, along with their meaning and the recommended corrective action. It
should be noted that if multiple (more than 2 or 3) warning messages occur at the same time, it is
often an indication that some fundamental analyzer sub-system (power supply, V/F board, CPU)
has failed rather than an indication of the multiple failures referenced by the warnings. In this
situation, it is recommended that proper operation of power supplies (see Section 9.6.4) and the
V/F Board (see Section 9.6.3) be confirmed before addressing the specific warning messages.
9-3