Teledyne 4060 manual Electronic Stability, Printed Circuit Board Replacement

Series 4060 Maintenance

2.If no reading is obtained, disconnect the anode-igniter cable and check for the voltage on pin “J4-1” of the connector located at PC board part number B74671. If the proper voltage is still not present, replace the flame guard and anode power supply PC board. If it is, check the wiring in the anode-igniter cable plug. If necessary, the circuit board can be replaced by first turning off the power, then removing 4 screws holding the board.

WARNING: DO NOT TOUCH CAPACITOR C1 OR C2 OR THEIR RELATED CIRCUIT FOILS. A SHOCK HAZARD MAY EXIST.

3.Carefully remove the circuit board without touching any connections which might lead to C1 or C2. After removal, discharge the two capacitors by placing a jumper wire across each.

4.The anode voltage may also disappear or be greatly diminished when condensation inside the sensor has occurred, shorting the igniter to the sensor body across the wet insulator. This usually occurs when the flame is turned on, if the sensor has not been preheated for at least 1 hour.

5.1.2Electronic Stability

If the checks outlined above indicate that conditions are normal, allow the analyzer to run electronically with the collector cable disconnected for several hours in the lowest range, and with the zero offset value adjusted so that the recorder is reading midscale. If all is normal electronically, a noise-free (pen width) recording, showing absolutely no instability, should be obtained for as long as the analyzer is allowed to run in this configuration. If the recording obtained is noisy or erratic, replace the electrometer-amplifier PC board.

5.1.3 Printed Circuit Board Replacement

If performance is not adequate, then the analyzer must be recalibrated as described in Section 4.6.5: Span before being placed back in service.

Teledyne Analytical Instruments 67