Silva NX2, Service Manual

Page: 44 / 77

91measurNX2.doc Page 4 Latest update: 8 Jan-03
If adjustment is required, press carefully the opto element (down end, not in top
end) in necessary direction to obtain smooth rotation of wind head. Check also
the four main directions to ensure stable and accurate readings. For calibration
see § 9.0.1.
9.1.5 REPLACING THE T-HOUSING, Art.No 18898
Dismantling
a) Unscrew the four screws and lift up the complete transducer head.
b) Unscrew the four screws fixing the nose cone. Lift off the nose cone.
c) Unscrew the four screws fixing the Vane and remove it.
d) Replace the T-housing and Re-assemble
9.1.6 REPLACING VERTICAL BEARINGS, Art.No 20402
Dismantling
a) Unscrew the four screws and lift up the complete
transducer head.
b) Unscrew the two screws holding amplifier PCB.
c) Lift up the PCB.
d) Ensure that the transducer unit is disconnected from
power supply.
e) Unsolder the four wires.
f) Use the socket wrench for removing the bolt with nut
and lift up the inner tube and replace defect bearings.
Re-assembly
In opposite order, but note the following:
−
Re-solder wires according to § 9.1.7g.
−
Be careful with the wires when they are put through the hole in the bottom of
inner tube. Bend them as illustrated before the amplifier PCB is pressed down
in place.
9.1.7 Replacing amplifier PCB
As the opto elements characteristics are adjusted and trimmed in the amplifier
during the production, the PCB should be replaced as a complete unit.
Dismantling
a) Unscrew and lift off the complete head.
b) Unscrew and lift up the amplifier board. Ensure that
transducer is disconnected from power supply.
Check/Replace PCB
c) Check the+12V supply on green: correct level? If no +12 V
on green wire check the plug connector, see § 9.6
d) Check Chanel A, white. Activate the opto element by
putting a finger to cover it, back and forth. The level, will
now shift between 0 V and 5 V
±
0,5 V. Replace the amplifier PCB if the output
is constant 0 V or 5 V.
e) Check signal in channel B, Yellow. Same procedure. Replace the amplifier
PCB if the output is constant 0 V or 5 V.
f) Un-solder the four wires.