CEMB USA T-NC_30-D User Manual
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TRANSDUCER POSITIONING
Refer to drawing Nr. 21566
1)
Drill holes on the machinery for the sensors support and for any cable protection
devices (sheaths, ducts etc.).
2) Drill a hole to fasten the converter box at a distance from the machinery shorter
than that of the connecting cable (5m).
3) Separate the sensors from the converter by disconnecting the cable from the terminal
board inside the converter (carefully note the polarity of the two leads making up
the cable), then mount the sensors on the support prepared in point 1
4) After checking that the machinery lies in position K (ZERO position with the
machine stationary), perform a preliminary mechanical adjustment of the sensors GAP
by acting on the nut-lock nut device of the sensor. The GAPS indicated in the
application drawing refers to the mid point of the measuring range of the
transducer. In the case of frontal measurement of the displacement, the mid point of
the measurement range of the sensors corresponds also to the mid point of the
measurement to be made. If the measurement is longitudinal (sliding of an inclined
block) instead of frontal, proceed to calculate the GAPS corresponding to the
position K of the machinery, taking due consideration of the measuring range and
angle of inclination of the block.
5) Fasten the converter box using the holes drilled in point 2 and attach any
protective sheaths if necessary. Reconnect the sensors cable to the converter
terminal board making sure of the exact polarity of the leads making up the cable.
6) Proceed to the electrical connection of the converter with the measuring
instrument.
7)
The following instructions refer to the machinery under the supply, with the machine
in position K and with the measuring instrument operating, use the nut-lock nut
device of the every sensor to search for the exact coincidence between the
mechanical GAP and the electrical calibration of the converter in the following
way:
- reading on a voltmeter connected across pins A and D of the converter connector
(or else across the terminals corresponding to the transducer signal input on
the terminal board of the instrument) on the scale 0 to 10 Vdc of the range of
measurement (0Vdc= scale start, 10Vdc=full scale) of the volts corresponding
to the Gap; as the Gap indicated in the application drawing of the transducers
refers to the mid point of the range of measurement, under this condition there
should be a corresponding reading of 5 Vdc.
Hence the sensor position should be adjusted through small displacements along its
longitudinal axis until the value of 5 Vdc on the voltmeter.
8) Then lock the sensors in position using the nut-lock nut device.
9) Close the converter making sure that it is spray- and dust-proof.
REMARKS REGARDING CORRECT POSITIONING OF TRANSDUCERS T-NC/S
1) Never, under any circumstances, modify the sensor / converter cable length: this
would cause a measuring error.
2) The end part of the sensor must lie at a distance from metal materials different
from the one involved in measuring the distance: at least twice the max. amplitude
of measurement (see application drawing).
3) When mounting the sensor, a reference cone should be prepared at 90° vertex from
the sensor tip. No metallic material must be introduced in the cone apart from the
surface to be measured.
UTS060208
ASTD60120