Carrier 69NT40-541-001, Operation And Service

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T-316 7–38
e. Mark today's date, container number, and other required information on the new chart and install under hold
down tabs.
f. Replace the chart nut loosely, rotate the chart until the correct day is aligned with the “start arrow,” and hand
tighten the chart nut.
g. Gently lower the stylus arm until the pen tip (item 4) comes in contact with the chart.
CAUTION
!
Do not allow the recorder stylus to snap back down. The stylus arm base is spring loaded, and
damage may occur to the chart, or the stylus force may be altered.
DO NOT move the stylus arm up and down on the chart face. This will result in damage to the
stylus motor gear.
7.23.3 Adjusting the Recorder Stylus
Proper stylus force upon the chart paper is important. Factory adjustment is 113 to 127 grams (4 to 4.5 ounces). To
measure the force, use a spring type gage, and attach it under the stylus as close as possible to the pen tip (item
4). Exert pull on the gage perpendicular to the chart surface. The measured force should be noted just as the pen
tip leaves the surface.
NOTE
The two coil springs near the base of the stylus are NOT involved in establishing chart contact force.
They serve only to hold the stylus in its retracted position.
Correct adjustment is made by carefully bending the portion of the stylus arm between the bend near the pen tip,
and the first bend towards the stylus arm base. If the force is too low, the stylus trace will be light and difficult to
read. If the force is too great, wrinkling, or tearing of the paper chart may occur.
7.23.4 Re-zeroing the Recording Thermometer
For Electronic Partlow Recorder CTD P/N 12-00464-xx
Where xx= an odd number (example: 12-00464-03)
NOTE
Use chart CTD P/N 09-00128-00 (°F), P/N 09-00128-01 (°C).
a. Press the “Calibration” button (item 7, Figure 7.29 ) on the bottom of the recorder. The pen tip will drive fully
down scale, then move upscale to the chart ring at -29°C (-20°F), and stop.
b. If the tip of the pen (item 4) is on the -29°C (-20°F) chart ring the recorder is in calibration, proceed to step c.
If the tip of the pen is NOT on the -29°C (-20°F) chart ring, the operator must loosen the two screws on the
bottom of the stylus arm to adjust the pen tip manually to the -29°C (-20°F) chart ring. Tighten the screws
when adjustment is complete.
c. Press the calibration button and the pen will position itself to the correct temperature reading.
For Electronic Partlow Recorder CTD P/N 12-00464-xx
Where xx= an even number (example: 12-00464-06)
NOTE
Use chart CTD P/N 09-00128-00 (°F), P/N 09-00128-01 (°C).
a. Press the “Calibration” button (item 7, Figure 7.29 ) on the bottom of the recorder. The pen tip will drive fully
down scale, then move upscale to the chart ring at 0°C (32°F), and stop.
b. If the tip of the pen (item 4) is on the 0°C (32°F) chart ring the recorder is in calibration, proceed to step c. If
the tip of the pen is NOT on the 0°C (32°F) chart ring, the operator must loosen the two screws on the bot-
tom of the stylus arm to adjust the pen tip manually to the 0°C (32°F) chart ring. Tighten the screws when
adjustment is complete.
c. Press the calibration button and the pen will position itself to the correct temperature reading.