RS COMPACT FREEZE TUNNEL, Руководство по эксплуатации и обслуживанию

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OPERATION & MAINTENANCE MANUAL
CompactFreezer
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When a freezer is installed, the LN2 lines are blown out to clear out debris. There is a strainer on each
LN2 drop line that should be cleaned about one time per year.
To clean the orifices, remove the nozzle. Probe the orifice in the nozzle with a fine pin and tap the
nozzle lightly to remove the foreign material from inside. Replace the nozzle, making sure to point the
orifices the same as they were.
9.9. TEMPERATURE CONTROLLER
FDC ‐ 4300 Fuzzy Logic plus PID microprocessor ‐ based controller, incorporates a bright, easy to read 4 ‐
digit LED display, indicating process value. The Fuzzy Logic technology enables a process to reach a
predetermined set point in the shortest time, with the minimum of overshoot during power
‐ up or
external load disturbance. The units feature three touch keys to select the various control and input
parameters. Our unit is powered by 11
‐ 28 or 90 ‐ 264 VDC/AC supply, incorporating a 2 amp control
relay output and dual 2 amp alarm relays output as standard. The unit is set up to digitally display
temperature in degrees F. There are LED status indicators to show activation of Outputs 1 and alarm 1
and the set point and ambient is displayed. The outputs are on/Off signals. Alarm 1 signal controls the
constant (throttled) low flow injection, and Out 1 signals the make
‐ up (full flow) injection. The lower
limit set point is programmed to not exceed ‐ 125°F ( ‐ 130°C), but can be reprogrammed for warmer
or colder limits if the situation warrants it.
Control functions, alarm settings, and other parameters are easily entered through the front keypad.
Programmed data is protected from unauthorized changes with its
“ENABLE MOD” security system.
Battery back ‐ up protects against data loss during AC power outages.
The instrument is removable from its housing. External wiring for the controller is connected to the panel
board at the back of the housing.
To remove the instrument from its housing, pull the instrument straight out.
When reinstalling, be sure that the vertically mounted circuit boards are inserted in the correct grooves
in the top and bottom of the housing.
The controller has a default circuit and is checked out at the time of freezer assembly. Should a
temperature control problem develop first check for loose connections to the controller and the
temperature sensor and the sensor connection in the module apparatus box.
9.10. TEMPERATURE SENSOR (RTD TYPE)
To replace the temperature sensor, disconnect leads inside the apparatus box, loosen compression nut,
fittings and remove fitting and sensor from within the apparatus box. Install new sensor by sliding it
through the same opening in the apparatus box;
the sensor should protrude 1” to 1‐1/2” down from the
ceiling of the module and be free from being hit by the fan blade. Connect new leads to proper wires of
shielded cable. A fitting is part of the new sensor.
To Replace Fan Shaft Bearing Only