6300 Rev H User’s Manual
125-9106A Page 34
Figure 3.20 : Static Control mode
‘Control’ will be blinking in the Static mode field. Also, ‘Control’ will be blinking in the Pitot mode field.
This is because when either Pitot mode or Static mode is changed to Control, both Pitot and Static modes
are automatically setup for Control. (Caution: Do NOT press GO at this moment). Pressing GO will
activate both Pitot Control mode and Static Control mode. Pressing CANC will revert both Pitot and
Static modes back to Measure. For now, press CANC and return Pitot and Static to Measure mode.
Note: When Pitot mode is changed to Control, Static mode is automatically changed to Control.
Similarly, when Static mode is changed to Control, Pitot mode is automatically changed to Control.
Note: Leak and Measure modes can be selected independently for Pitot and Static.
3.6.1 MEASURE TO CONTROL TRANSITION
When either a Pitot or Static output is changed from Measure or Leak to Control mode, a sequence of events
takes place that needs explaining. Since the controlling portion of the 6300 is isolated from the output during
Measure or Leak modes, it will usually be at a pressure quite different from that at the output. Simply
introducing the controlling section into the pneumatic system connected to the output will cause a surge in
pressure at the output. To prevent such a surge, the 6300 measures the pressure at the output, shuts-off the
output from the internal 6300 pneumatics, and then controls the pressure within the internal control
mechanism to match the pressure at the output. Once this is done, the 6300 controlling section is connected
to the output. This process is termed as Equalization.
While the 6300 is undergoing this process, the term 'EQZN' is displayed on the screen in place of the
“Actual” values. When the outputs are close to “Ground”, the EQZN process usually takes about 15 seconds
or less to complete. When the outputs are not close to “Ground”, usually the process is completed almost
instantly and ‘EQZN’ may or may not appear on the screen.
When the outputs are close to “Ground”, following the Equalization process, the 6300 will automatically
inject a small vacuum on the Static output and a small pressure on the Pitot output. This is done to
determine the volume of the Pitot and Static system on the aircraft, so that the 6300 can automatically adjust
the gain of its control mechanism. Due to this, the actual value will always increase in both altitude and in
knots for about 5 seconds, regardless of the target value. Once this process is complete, the actual values will
move towards the target values.
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