Basic Interfacing
Our propeller de-icing system composes of a single propeller de-ice controller unit, the PDC.
The diagram below illustrates the basic interfacing to the operator and the propeller heating boots.
Operator Interface
The pilot has one switch to control and two annunciation lights to monitor:
-
The PROP-HEAT switch will turn de-icing ON or turn it OFF. A three position switch may alternatively be employed to
provide two levels of heating, either HIGH or LOW when not turned OFF.
-
The HEAT-ON light will light-up when de-icing is turned ON.
In case of de-icing failure while turned ON, this light will blink continuously.
Otherwise, when PROP-HEAT is turned OFF, the HEAT-ON light will go out.
-
The HEAT-FAIL light will light-up when a failure has been detected while de-icing is turned ON.
Failure results when the electrical current flowing to the heating boots falls out of the configured bounds.
Propeller Heating Boots
The PDC is normally installed within the engine compartment (in front of the firewall) and receives its power locally.
This minimizes the wire-count through the firewall and increases efficiency by reducing the distance the de-icing current
have to flow to get to the propeller blade heating boots.
The PDC applies power to the boots directly (without the need for extra power relays)
via the slip-ring assembly at the back of the propeller hub.
We combine pins in parallel on the PDC connector to facilitate the switching of relatively high electrical currents through the unit.
Operational Scenario
You switch the aircraft MASTER switch ON and both HEAT-ON and HEAT-FAIL lights up for about 2 seconds while
the PDC performs a system self-check. The lights go out to show it is ready for use.
As part of your pre-flight or during flight you decide to turn PROP-HEAT ON and notice that the HEAT-ON light lights up
while the HEAT-FAIL stays dark.
As the heating cycle continues the system moves from energizing phase A to energizing phase B and you notice the HEAT-ON
light blink once or twice to mark this transition. These blinks continues every so often informing you of the
phase transitions and correct operation, giving you added peace of mind.
Suddenly there is a problem with either the heating boots, the slip-rings or the electrical wiring and the HEAT-FAIL
light immediately lights up while the HEAT-ON light starts flashing continuously. You realize that the system is still
cycling through the phases, but that propeller de-icing is not working properly and you start taking appropriate action.
Maintenance Operations
From time to time a Laptop PC and USB-to-Serial Converter may be connected to the PDC,
as depicted below, in order to perform maintenance operations on an installed system.
Maintenance operations allow you to confirm (troubleshoot) your installation, make adjustments,
view operational information and record a certain operation. All these tasks are done through the
VR System Link software running on the laptop.
System Link enables making adjustments to set-points, calibration values and
other configuration settings, such as setting the working current minimum and maximum limits.
More Information
Additional information is contained in our PDC manual, wiring diagrams, etc. listed in the colum
on the right side of the web page. You'll also find PDC firmware updates here that we provide free of charge to all customers.
This firmware will be updated from time to time to provide additional features and improvements.
Also, please feel free to contact us with any query you may have regarding any of our products.
|