General Troubleshooting & Service Teledyne API T703/T703U Calibrator Operation Manual
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8.5.2. CHECKING MEASURE / REFERENCE VALVE

To check the function of the photometer’s measure / reference valve:
1. Set the calibrator’s front panel display to show the PHOTO REFERENCE test
function (see Section 4.1).
2. Follow the instructions in Sections 6.1.1 and 6.1.3.1 for performing a zero point
calibration of the photometer.
Press XZRO and allow the calibrator to stabilize.
3. Before completing the calibration by pressing the ZERO button, note of the displayed
value.
4. Press the final Zero button, then press “NO” when asked, “ARE YOU SURE”.
5. Follow the instructions in Section 6.1.3.2 for performing a span point calibration of the
photometer.
Press XSPN and allow the calibrator to stabilize.
6. Before completing the calibration by pressing the SPAN button, note of the displayed
value of PHOTO REF.
If the O3 REF value has decreased by more than 2 mV from its value with Zero-
gas, then there is a "cross-port" leak in the m/r valve.
7. Press the final Zero button then press “NO” when asked, “ARE YOU SURE”.

8.6. TROUBLE SHOOTING THE O3 GENERATOR

Troubleshooting the O3 generator differs between the T703 (Section 8.6.1) and the
T703U (Section 8.6.2).

WARNING

Hazardous voltage present - use caution.

8.6.1. TROUBLESHOOTING THE O3 GENERATOR IN THE T703

(See Section 8.6.1 for troubleshooting the T703U O3 generator).
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 8.4.3.
3. Begin generating O3.
4. Scroll to the Test Function O3GENDRV and note the reading in mVDC [XXXX.X].
5. Remove the cover of the O3 generator and check for the presence of the following
voltages on the UV lamp power supply PCA:
Reading between TP1 and TP4 (grnd) should match the O3GENDRV test
function reading [XXXX.X] mVDC ± 10 mVDC
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.
Reading of +5VDC should be seen 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.
07223C DCN6572