Specifications

Table Of Contents
Chapter 2 Service
Troubleshooting the Counter
150 Assembly-Level Service Guide
Troubleshooting the Counter
This section provides a brief check list of common failures. Before
troubleshooting or repairing the instrument, make sure the failure is in
the instrument rather than any external connections. Also make sure that
the instrument has been accurately calibrated within the last year.
The instrument’s circuits allow troubleshooting and repair to an assembly
level with basic test equipment.
Unit is Inoperative
Verify that the AC power cord is connected to the instrument and to
an AC power source.
Verify that the front-panel On/Standby switch has been pressed.
Unit Fails Self-Test
Ensure that all terminal connections (both front panel and rear panel
terminals) are removed while the self-test is performed.
Power Supply Check
WARNING HAZARDOUS VOLTAGES ARE ON THE POWER SUPPLY
ASSEMBLY. ONLY SERVICE TRAINED AND QUALIFIED
PERSONNEL SHOULD PERFORM THE FOLLOWING
PROCEDURE.
1 Remove the power cord from the back of the instrument to
disconnect the counter from the power source.
2 Remove the cover as described in Chapter 3.
NOTE The AC Power Supply Assembly is internally fused for safety
reasons. It is assumed that if the internal fuses are blown, then
damage has occurred to the power supply which will make it
unreliable. Do not attempt to repair the power supply.