Checking The Uv Lamp Power Supply - Teledyne T700 Operation Manual

Troubleshooting and Service

9.5.3. CHECKING THE UV LAMP POWER SUPPLY

Note
268
A schematic and physical diagram of the Lamp Power Supply can be
found in Appendix D.
Hazardous voltage present - use caution.
It is not always possible to determine with certainty whether a problem is the result of
the UV Lamp or the Lamp Power Supply. However, the following steps will provide a
reasonable confidence test of the Lamp Power Supply.
1. Unplug the cable connector at P1 on the Lamp Power Supply and confirm that
+15VDC is present between Pins 1 and 2 on the cable connector.
2. If this voltage is incorrect, check the DC test points on the relay PCA as described
in Section 9.4.3.
3. Remove the cover of the photometer and check for the presence of the following
voltages on the UV lamp power supply PCA (see Figure 10-20):

+4500 mVDC ±10 mVDC between TP1 and TP4 (grnd)

If this voltage is incorrect, either the UV lamp power supply PCA is faulty or the
I2C bus is not communicating with the UV lamp power supply PCA.

+5VDC between TP3 and TP4 (grnd)

If this voltages is less than 4.8 or greater than 5.25 either the 5 VDC power
supply or the UV lamp power supply PCA are faulty.

If the above voltages check out, it is more likely that a problem is due to the UV
Lamp than due to the Lamp Power Supply.

Replace the Lamp and if the problem persists, replace the Lamp Power Supply.
Teledyne API – Model T700 Dynamic Dilution Calibrator
WARNING
06873B DCN6388