Valve Driver Pca; Valve Driver Pca Watchdog Indicator; Figure 10-8: Status Led Locations - Valve Driver Pca - Teledyne T700 Operation Manual

Teledyne API – Model T700 Dynamic Dilution Calibrator

10.3.4. VALVE DRIVER PCA

10.3.4.1. Valve Driver PCA Watchdog Indicator

06873B DCN6388
The valves that operate the T700 calibrator's main source gas and diluent gas inputs are
controlled by a PCA that is attached directly to the input valve manifold (see Figure 3-5
or Figure 3-6). Like the relay PCA, the valve driver PCA communicates with T700's
CPU through the motherboard over the I
Figure 10-8: Status LED Locations – Valve Driver PCA
The most important of the status LEDs on the relay PCA is the red I
LED. It is controlled directly by the calibrator's CPU over the I
watchdog LED on the relay PCA, should this LED ever stay ON or OFF for 30 seconds
2
if the CPU or I C bus has stopped functioning, this Watchdog Circuit automatically
shuts all valves and turns off all heaters and lamps.
2
C bus.
Principles of Operation
2
C Bus watchdog
2
C bus. Like the
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