Videotec PHT355P, Operating Instructions Manual

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Pag. 5 MNPTH3553803
Adjustment of the potentiometer for PTH355P preset pan & tilt motor
This operation is very important for the correct working of the preset.
PTH355P Pan & Tilt motor is still set in our works, therefore this procedure is to be made only in case of real
necessity.
The following procedure has to be followed both for the potentiometer connected with the horizontal movement and for
the one connected with the vertical movement.
1. Disconnect the pan & tilt motor supply
2. Adjust the cams by means of a screwdriver
until their position is symmetric compared to
the end of stroke
3. Loosen the fixing screw “ A ” and the nut “ B ”
of the potentiometer holder bar of the
horizontal movement
4. Release the pinion from the gear
5. Place an Ohmmeter between the Vcc and
Pan clamps of the terminal strip J4 and turn
the potentiometer shaft, which is connected
to the horizontal movement, till reading the
value of about 3750 Ohm.
6. Replace the potentiometer gear
7. Lock the fixing screws “
A ” and the nut “ B ” of
the potentiometer holder bar of the horizontal
movement
8. Repeat the same operation for the vertical
movement till reading the potentiometer
value between Vcc and Tilt clamps of the
terminal strip J4.
A B