THRUSH AIRCRAFT, INC – MODEL S2R-R1340
AIRCRAFT MAINTENANCE MANUAL
Effective: 01/01/08
8-11
*NOTE*
A scale is provided to show
the relationship of the remote
gauge, % scale on analog
control unit type FA-A, and
number of inches the bottom
of the floating ball is away
from the top of the lower stop
collar. The column labeled
ground shows how many
gallons are in the hopper with
the aircraft in the ground
attitude in relationship to the
remote gauge reading.
Calibration of Hopper Quantity Gauge
A. The remote hopper level gauge
markings are an indication of hopper
load in level flight.
B. A screw type adjuster located on the
face of the gauge at the six o’clock
position adjusts the remote gauge 0
mark. Adjustment of the screw CW
or CCW will move pointer left or
right.
C. With floating ball against lower stop
collar, adjust screw adjuster until
pointer is aligned with 0 marks on
gauge.
D. The 360-gallon mark is adjusted by
turning a screw head located on a
20K ohm potentiometer on a circuit
board attached to rear of gauge.
E. With floating ball against the top stop
of the sending unit; adjust the
potentiometer until pointer is aligned
with 360 marks on gauge.
*NOTE*
Unit must be on to adjust 360
side of gauge.
*NOTE*
The small % scale on analog
control unit Type FA-A will
move in direct relationship
with the remote gauge.
F. Once steps C and E are completed,
the unit is in calibration.
*NOTE*
Hopper loads above 360
gallons are un-gaugeable.
Also provided with the system are two
hopper-level warning lights: one amber
and one red. They both have a push-to-
test feature and a dimming capability.
The lights are adjusted to come on at
any position (hopper level) that you may
desire by potentiometers located under
pop-off caps on the face of the analog
control unit Type FA-A. The amber light
is adjusted to come on by adjusting Pot
1 labeled set point 1, and the red light is
adjusted to come on by adjusting Pot 2
labeled set point 2.
The amber and red lights can be set at
any position you may desire. Thrush
Aircraft Inc recommends setting the
amber light to come on at 25 gallons, or
8 3/8" from top of lower stop collar to
bottom of floating ball, and the red light
to come on at 6 1/2 gallons, or 2 1/2"
from top of lower stop collar to bottom of
floating ball.
INSTRUMENT
TROUBLESHOOTING
Table 8-1, starting on the next page,
gives helpful information to track down
the cause of instrument problems.
