COMPTROL 36 - Page 7

MODEL 36, TYPE B & C
SINGLE RANGE TENSIONCELLS
INSTRUCTION MANUAL A-279
7
Copyright 2023 - Revised Comptrol All Rights Reserved
3. With a voltmeter connected to Pins C and D of the
connector, an output voltage will be observed.
4. Repeat Step 3 for the Tensioncell mounted on the
opposite end of the measuring roll.
Comptrol loadcells instrumentation provides the required
signal conditioning and a reliable high level output signal
for use as feedback control of a tension drive system.
The feedback signal is directly proportional to the strip
tension applied. If a Comptrol control is used, refer to the
control manual for further calibration.
Although the electrical output of Comptrol Tensioncells
are sufficient to drive most electrical indicators,
substantial signal conditioning is normally required for
effective tension instrumentation system control. Refer to
the documentation available from the instrumentation
supplier for more information.
PART Ill – TROUBLE SHOOTING
When properly installed in accordance with the original
design specifications, Comptrol Tensioncells should
require little or no regular maintenance or service.
Certain conditions, however, can impair their inherently
accurate and reliable performance. Therefore, if trouble
should arise, the following conditions should be checked.
III-A MECHANICAL
1. Has the tension measuring system been changed?
a. An increase or decrease in web tension. (Refer to A
on the calibration sheet for specified web tension)
b. An increase or decrease in the wrap angle. (Refer to
B on the calibration sheet for the specified wrap angle)
If the above parameters have been changed enough to
prevent the unit from operating within the limits of the
fixed Mechanical Stops, replacement of the Flexure will
be required. For this modification, the Tensioncell should
be returned to the factory with complete specifications.
2. Are the loadcells mounted securely?
3. Is tension measuring roll in proper alignment and does
it turn freely?
4. Are bearings and seals free of all binding and
stickiness? Are they worn?
III-B ELECTRICAL
1. Are LVDTs receiving correct input voltage?
Check line voltage, fuses or circuit breakers, and power
switches. Check power supply output and voltage to
LVDTs.
2. Are all connections secure?
Check for continuity. Retighten all connections. Recheck
operation.
3. Are LVDTs open or shorted.
To check, turn off power and disconnect the input and
output leads. Check coil continuity and resistance.
(Refer to Figure 4)
a. Pin A to Pin B (Primary Coil) should be in excess of 2
megohms.
b. Pin A or Pin B to LVDT shell should be in excess of 5
megohms.
c. Pin C to Pin D (Secondary Coil) should be
approximately 20,000 ohms.
d. Pin C or Pin D to LVDT shell should be in excess of 5
megohms.
If LVDT circuits are open or shorted, replace LVDT.
Contact Comptrol with Tensioncell model number and
serial number.