Piper Navajo PA-31 Service Manual page 252

PIPER NAVAJO SERVICE MANUAL
VC VL
VR
DOWN Position
X.XX
X.XX X.XX
UP Position
X.X X.X
X.XX
22. The values at the DOWN position have already been established for VC. VL. and VR in step 17
preceding. At this time enter the reading for VC. VL and VR at the UP position. The work sheet might now
resemble the following example (voltage values used in this example are for illustrative purposes only. They
are NOT system requirements):
VC
VL
VR
DOWN
9.15
8.95
8.95
UP
4.06
4.38 (See
4.36 (See
step c & d)
step c & d)
CAUTION
No adjustments are to be made at the wing rheostats (RL and RR)
until the flap motor circuit breaker is pulled.
c.
If VL and VR differ by more than .50 volts, an out of sync, shutdown has occurred due to an
actuator arm being loose on the rheostat shaft. If this has happened. place a jumper wire between RL and R R
at the amplifier and select flaps full DOWN. Pull flap motor circuit breaker and readjust voltages at RR and
RL as per step 17 and begin again.
d.
If VL is within .04 volts of VC the System has shut down because amplifier sees that the position
selected (VC) and the position sensor (VL) have been satisfied. If this has happened, reselect flaps to
full DOWN, readjust voltages at RL and RR per step 17 with greater spread between VL. VR and VC. than
the initial adjustment.
e.
If the system has completed a full stroke (up limit switch has been engaged) and the flap position
indicator reads correctly,m no further adjustment is necessary. (It is considered acceptable if the indicator
pointer center line is tangent to the upper or lower edge of the indicator graduation mark.) This is provided
that VLand VR are within the limits of step 17. Proceed to step h. If position and or indicator criteria are not
satisfied proceed as follows: Calculate VC by the formula VCI = VC + (10 + 10 -.05).
1.
Calculate the voltage difference between VC1 and VL, VC1 and VR as measured in the UP
position. Multiply the voltage difference by 2 as shown in the following example:
Voltage Difference
Voltage Difference
between VC1 and VL between VC1 and VR
Flap
VC VC1
VL VR Higher
Lower Higher
Lower
UP 4.06 4.16
4.38 4.36
VCL
VCR
= .22v = .20v
x
2
DOWN
9.15 N/A
8.95 8.95
Adj. = .44
Adj. = .40
CAUTION
Make no adjustments until the flap motor circuit breaker is pulled
OFF.
Revised: 10/12/83
SURFACE CONTROLS
Effectivity
CALCO
1K12