Koehler K18854, Operation And Instruction Manual

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Low Temperature Torque Apparatus
Operation and Instruction Manual
K18854,55,64,65-Manual
- 16-
4. Turn on the power to the unit and permit the
display to stabilize. Check the panel reading
against the reading in the load cell manual.
Adjust as necessary using the setscrew on the
lower left side of the panel meter. Confirm that
the serial number of the load cell corresponds
with the one in the manual.
Calibration for the left-side (ASTM D1478)
Test Rig:
NOTE: Resistor value and load cell
constants are pre-programmed in the display
meters. Only need to calibrate with standard
weights provided.
With no rod attached and no load applied on
the left side the display should read “0”.
Screw in rod and place load #1 onto the rod.
The display should now read a negative value
of 11 lbs. Each additional weight should
register an additional 11 lbs. Continue adding
loads until reaching desired calibration range.
Adjust span screw on display accordingly to
calibrate to equivalent negative weight.
Calibration Procedure “B” ASTM D4693 only:
Included with the Low Temperature Torque
Apparatus is a set of 5 kg calibration weights.
Three of these weights are 5 kg. The fourth,
marked #1, totals 5 kg when used with the
threaded support rod. These weights are to be
used to measure calibrate the ASTM D4693 load
cell only.
1. Turn the power on and let the unit run for
several minutes.
2. Remove the threaded rod from the load cell
and zero the strain gauge indicator.
3. Insert the weight support rod and slip on the
weight marked #1. The strain gauge should
display 11 lbs. Each additional weight should
register an additional 11 lbs. Adjust the span
screw to make any correction.
NOTE: Handle weights very carefully
when placing them on the load cells as they
are delicate instruments. Rough handling of
the weights may change their 5 kg value.
Load Spring Calibration
Check the calibration of the load spring on the
ASTM D4693 test rig four times per year. A
calibrated spring tester is recommended for this
purpose.
6 Safety Features
The Koehler Low Temperature Torque
Apparatus is equipped with several safety and
protection features, which are described in the
following sections.
6.1 Over-Temperature Protection
The
Koehler Low Temperature Torque
Apparatus is equipped with Over-temperature
Protection (OTP) circuitry, which prevents the unit
from exceeding unsafe operating temperatures. If
the unit cannot maintain the set point temperature
and begins to decline, the OTP circuitry may have
been activated. Please follow these steps.
1. Turn off the unit power switch and disconnect
the line cord.
2. Determine the source of the problem and
correct the situation.
3. Restart the unit. Monitor the operations to
ensure that the unit is operating properly. If
you are still experiencing trouble, please
contact
Koehler technical service for
assistance.
6.2 Over-Power Protection
The Koehler Low Temperature Torque
Apparatus is equipped with Over-power Protection
circuitry, which prevents the unit from unsafe
electrical conditions. If power to the unit is lost,
then turn off the main power and turn it back on
again. The main power switch also functions as a
circuit breaker.