Teledyne MODEL T703 Manual Do Utilizador

The Relay PCA can be most easily checked by observing the condition of the status LEDs located along its 
upper edge (see Section 11.3.2 and Figure 11-3: Relay PCA Status LEDS Used for Troubleshooting), and using 
the SIGNAL I/O submenu under the DIAG menu (see Section 11.1.3) to toggle each LED ON or OFF.  

If D1 on the Relay PCA is flashing and the status indicator for the output in question (Pump power, Heater 
power, Valve Drive, etc.) toggles properly using the Signal I/O function, then the associated control device on the 
Relay PCA is bad.  Several of the control devices are in sockets and can be easily replaced.  The table below 
lists the control device associated with a particular function. 

UV Lamp Heater 

Q2 

No 

O

3

 Gen Heater 

Q3 

No 

All Valves 

U5 

Yes 

AC Dry air Pump 

K1 

No 

DC Photometer Pump 

U1 

No 

 

 

 

This assembly is only present in calibrators with O

3

 generator and/or photometer options installed.  The 

pressure/flow sensor PCA, located at the rear of the instrument between the O

3

 generator and the photometer 

pump (see Figure 3-5) can be checked with a Voltmeter.  The following procedure assumes that the wiring is 
intact and that the motherboard as well as the power supplies are operating properly: 

  Measure the voltage across C1 it should be 5 VDC ± 0.25 VDC.  If not then the board is bad 
  Measure the voltage between TP2 and TP1 C1 it should be 1o VDC ± 0.25 VDC.  If not then the board is 

bad. 

07223B DCN6378