ARPLAST PV-50, Руководство пользователя

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Page 2 of 8 © Lyndhurst Touchdown Services Limited updated February 2007
Explanation
The system works using an electric motor supply voltage of -7.2 or +12 volts ( normally + ve on the
central core of the propeller to increase blade pitch). The rechargeable batteries are delivered charged
and their voltage may be checked by applying a voltmeter to the contacts on the battery pack ( 7.2 v). The
control box should be sited carefully - AVOID the possibility of short circuit as the rechargeable batteries
are capable of discharging high current which would be undesirable and could even lead to fire. The
batteries are recharged automatically during flight (in fact after the master switch has been switched on).
The micro switches that limit movement of the lead screw are protected by an aluminium tube which is
secured with a metal spring. Do not use mastic or glue as this may inhibit the release of condensation.
In most cases pitch variation between take off and fast cruise will not exceed 8 degrees. The propeller can
be configured to provide reverse or feathering. If you wish to use the full range of settings please contact
sarl HELICE or Lyndhurst Touchdown Services Limited for further advice.
Control Mechanism ( for engines without Vac Pump )
Fit the control mechanism behind the reduction drive using locktite on the screws provided. The control
rod must be kept straight. The control rod may be insulated with heat shrink sleaving but the end must not
be allowed to earth out on the casing or on the hollow shaft. The control rod must be placed directly in the
centre of the hollow shaft. Cables and other parts of the system should be kept clear of the control rod.
DO NOT route potentiometer cables near other electrical cables especially the Rotax alternator & ignition
cables.
Control Mechanism ( for engines with Vac Pump )
Fit the control mechanism on the engine block behind the reduction drive using the tapped holes in the top
of the engine block. Use locktite or wire lock (screws not provided). The control rod must be kept straight.
The control rod is normally insulated with heat shrink sleaving but the end must not be allowed to earth out
on the casing or on the hollow shaft. The control rod must be placed directly in the centre of the hollow
shaft. Cables and other parts of the system should be kept clear of the control rod. DO NOT route
potentiometer cables near other electrical cables especially the Rotax alternator & ignition cables.
Calibrating On 912 series engines fitted with a Vac Pump calibrate before reinstalling water distributor !!!
The digital display shows three digits for example 182. This would correspond to 18.2 degrees normally
measured at ¾ diameter. We suggest that the digital display is calibrated at your minimum pitch setting
determined after flight testing (around 17 degrees for a 80 hp 912 powered Europa ). The pitch
information is collected by the potentiometer on the control mechanism. The nylon arm is a push fit of the
potentiometer shaft and can be rotated to calibrate the display. Set the propeller to the minimum pitch for
example 17°’ then adjust the arm position on the potentiometer shaft to give 17° or 170 on the display.
Maximum and minimum pitches should be placarded on the panel.
Preparation
Place the hub motor down-most on a table (one with a hole drilled in it is easiest or on suitable packs).
Undo the short hub bolts and carefully remove the back of the hub half. Remove the swash plate notice
held with tape on the swash plate. Whilst holding the swash plate preventing it from rotating apply 6v or
12v to the motor. Drive the swash plate away from the motor until the lower half of the swash plate is flush
with the hub face. WARNING operating the hub with power applied directly to the motor disables the limit
switches and could result in damage to the hub. Power can be applied via the hub casting and the pickup
in the end of the swash plate shaft.
Remove the blades from their packing. Some counter weights are fitted with several additional washers
which may be temporarily removed at this stage. Loosen counter weights so that they can be turned on
the blade foot and apply a little grease to the nylon blocks. The blades and hub are marked and blades
must be placed in the correct slot in the hub.
Correct Nylon Bush Alignment
Necessary because the blades are angled
in the hub at 2.5 degrees. The bush is
drilled at an angle and must be rotated to
give the correct orientation in the swash
plate.
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