Teledyne T100 Manuale Utente

The relay board circuit can most easily be checked by observing the condition of its 
status LEDs as described in Section 12.2, and the associated output when toggled on and 
off through the SIGNAL I/O function in the DIAG menu, refer to Section 5.9.1. 

  If the front panel display responds to button presses and D1 on the relay board is not 

flashing, then either the I

2

C connection between the motherboard and the relay 

board is bad, or the relay board itself is bad. 

  If D1 on the relay board is flashing, but toggling an output in the Signal I/O 

function menu does not toggle the output’s status LED, the there is a circuit 
problem, or possibly a blown driver chip, on the relay board. 

  If D1 on the Relay board is flashing and the status indicator for the output in 

question (heater, valve, etc.) toggles properly using the Signal I/O function, but the 
output device does not turn on/off, then the associated device (valve or heater) or its 
control device (valve driver, heater relay) is malfunctioning.  

Several of the control devices are in sockets and can easily be replaced. The table below 
lists the control device associated with a particular function: 

Valve0 – Valve3 

U5 

Yes 

Valve4 – Valve7 

U6 

Yes 

All heaters 

K1-K5 

Yes 

12.6.7.1. A/D FUNCTIONS 

A basic check of the analog to digital (A/D) converter operation on the motherboard is 
to use the Signal I/O function under the DIAG  menu. Check the following two A/D 
reference voltages and input signals that can be easily measured with a voltmeter. Using 
the  Signal I/O function (refer to Section 5.9.1 and Appendix D), view the value of 
REF_4096_MV and REF_GND. 

  The nominal value for REF_4096_MV is 4096 mV   10 mV.   
  The nominal value for REF_GND  is 0 mV  3 mV, respectively, of their nominal 

values (4096 and 0) and are  

  If these signals are stable to within ±0.5 mV, the basic A/D converter is functioning 

properly.  

  If these values fluctuate largely or are off by more than specified above, one or more 

of the analog circuits may be overloaded or the motherboard may be faulty. 

  Choose one parameter in the Signal I/O function such as SAMPLE_PRESSURE 

(refer to previous section on how to measure it). Compare its actual voltage with the 
voltage displayed through the SIGNAL I/O function. If the wiring is intact but there 
is a difference of more than ±10 mV between the measured and displayed voltage, 
the motherboard may be faulty. 

06807C DCN6650