LumaSense Technologies M67 - Manual (Page 39)

M67, M67S Manual
38
10.5 M67 peak/valley picker
10.5.1 Description
The peak picker allows the M67 to react immediately to increasing target temperature and decay in a linear form until the
output equals the present target temperature. This is useful when the target is moving such as bottles on a conveyor belt.
Without the peak picker, the M67 output would be a series of pulses. The height of the pulse would represent the bottle
temperature and the bottom of the pulse, the background when a bottle is not present. This type of signal would, of course,
cause havoc with any recording or control device connected to the M67. When the peak picker is on, it will respond to the pulse
height and slowly decay at a rate set accordingly to the “DECAY RATE CONTROL” until the next pulse arrives. In summary,
the output will be smoothed and nearly represent the pulse the pulse heights (bottle temperature).
10.5.2 On-off control
To turn the peak picker on, use a small screwdriver to gently push in and turn clockwise approximately 45 degrees. To turn off,
push in slightly and turn counterclockwise 45 degrees and the switch will push itself out.
10.5.3 Decay rate
While the M67 is viewing your moving targets, adjust the control from fast to slow until the output is smoothed according to
your control or indication needs.
10.5.4 Reset
Peak pickers occasionally require resetting especially after power is first applied to the M67. Occasionally upon power up, the
peak picker will be set at full scale. Reset is accomplished by turning the decay rate control fully clockwise.
11. Maintenance
11.1 Lens cleaning
Since there are no moving parts in the M,.521 INFRADUCER, the only regular maintenance required is periodical inspection
of the lens and/or windows (if used) for build-up of foreign particles that, in time, can reduce the energy received by the sensor.
Lenses and windows used by /XPD6HQVH are not water soluble and can, therefore, be cleaned with standard lens tissue and solutions
available at camera stores. A soft blower/brush (also at camera stores) should be used to remove any grit on the lens before
rubbing with lens tissue and solution.
NEVER CLEAN A LENS WITH A DRY TISSUE OF ANY KIND!!!
Tissue is used only to dry a lens that has already been cleaned with wet lens tissue. Do not rub the lens excessively; let the
cleaning solution do the work, otherwise damage to the lens coating may result. Please refer to the special note for use with
closed loop control (Section 10.3, page 36).
11.2 Calibration maintenance
In very hot or dusty environments, the following procedure is recommended: Obtain a spare INFRADUCER. Replace the unit
in operation with the spare while cleaning the original. A complete exchange can be done in less than five minutes (low ranges
require approximately 1/2 hour warm-up to stabilize). Since the calibration and emissivity are repeatable within 1% between all
INFRADUCERS of the same range, no set-up time is required.
See trouble shooting chart (Section 12, page 40) before attempting to recalibrate. The instrument was calibrated at the factory to
±0.5% of span and should not need to be adjusted. Erroneous temperature readings are usually caused by installation problems
or other factors. The following items deserve special attention:
1. Emissivity factor. Follow instructions in Section 9, page 33 to determine the actual emissivity of target.
2. Low readings may be caused by the target being too small (not filling field of view). Refer to Field Of View (FOV)
diagrams at the beginning of this manual. Also, the instrument may not be aimed correctly.
3. High readings may be caused by reflections from another source, especially if the target emissivity is less than 0.8 (refer to
“Reflections” in Section 6.4, page 13).
4. Dirty lens (see “Lens Cleaning” in Section 11.1, page 38).
If all the above checks do not resolve the problem, special adjustments may be made on site as follows: