Checkline CTM User Manual
Checkline Sensors

Table of Contents
1.0 Introduction ......................................................................................................................... 3
1.1
Unpacking
................................................................................................................... 3
1.2
Description
.................................................................................................................. 3
1.3 Important features ....................................................................................................... 4
2.0 Operation
5
2.1
Typical
Operation
........................................................................................................ 5
2.2
Measurement
Practices
.............................................................................................. 6
2.3 Softkey Functions ....................................................................................................... 7
3.0 Confi guration Mode ............................................................................................................ 11
3.1 Accessing the Confi guration Mode ........................................................................... 11
4.0 Changing Sheaves ............................................................................................................. 14
5.0 Achieving Best Accuracy .................................................................................................... 15
5.1
Accuracy
................................................................................................................... 15
5.2 Calibration to Specifi c Wire Type ............................................................................... 15
5.3 Loading Error ............................................................................................................ 15
5.4
Non-repeatability
....................................................................................................... 15
5.5
Non-linearity
.............................................................................................................. 16
5.6
Wire
Characteristics
.................................................................................................. 16
6.0 Troubleshooting .................................................................................................................. 16
1
Most three-point tension meters employ only linear characterization and
have large errors at the midpoints (up to 15%). The CTM uses multi-point
segmenting to correct for non-linearity, reducing it to less than 0.2%.
Creep
Every material including steel exhibits creep under load. It will
neck down over time, quite quickly over the fi rst few seconds
and much slower as time progresses. A wire cable also sees
creep from the wire spacing and wind. This effect is seen as a
display that drifts lower after it has been clamped in line.
Variations
Material that varies in diameter or shape will have different
output at the same tension
Strands
The best cable assembly is one that is perfectly round, as
it will not change contact geometry with the wire twist. The
closer the wire cable cross section appears to be round, the
better the measurement performance will be.
5.5 Non-linearity
5.6 Wire Characteristics
16
Problem
Possible Cause
Solution
Powers on momen-
tarily and turns off
Low battery
Replace with high quality alka-
line batteries
Does not power on
Low battery
Replace with high quality alka-
line batteries
Batteries installed
backwards or no
spring contact
Insure that positive terminals
of both batteries (nub) face in-
ward – towards the black cap.
Check that spring is attached
to the battery cap.
Software reset
Remove battery cap & reinstall
after one minute. Attempt to
turn power on again.
Display contrast too
light
Hold the Right Arrow key down
while pressing the F2 key
several times to increase the
display contrast. If nothing oc-
curs, release both keys. Press
the power button and try again.
Display is
completely dark
Display contrast too
dark
Hold the Arrow key down while
pressing the F1 key several
times to decrease the display
contrast.
Display drifts down-
ward once installed
Wire material is
creeping and inter-
nal friction between
wires is relieved.
This is normal behavior of
wire. Lower display resolution
to mask this effect.
Temperature not
accurate
Instrument changed
temperature envi-
ronments
Allow instrument to remain in
environment until temp stabi-
lizes or enter temp manually
Instrument exposed
to sun
Enter temp manually
6.0 Troubleshooting