Taylor TW-357 - Manual (Page 43)

TW-357 REV E
43
Defog Feature Will Not Operate
See LID OPEN ALARM.
To activate or adjust times: Select MENU, USER OPTIONS, CONTROL OPTIONS, LID/DEFOG
SETTINGS, AUTO DE-FOG.
Push Buttons Will Not Respond
1. Check all ribbon cable connectors on back of display panel.
2. Moisture may have migrated into the sealed faceplate. Call Taylor-Wharton for a
Return Authorization.
Liquid Level Readout is Incorrect
Liquid level is determined by a seven-thermistor assembly inside a protective sensor tube. The user may adjust
the desired START FILL elevations and STOP FILL elevations for the pool of nitrogen with the confines of
the four inches. The EX-LOW LEVEL ALARM is automatically assigned to the thermistor below the
START FILL assignment, and the EX-HIGH LEVEL ALARM automatically reserves the thermistor above
the STOP FILL thermistor assignment. For this reason START FILL cannot be assigned to thermistor number
1. Similarly, STOP FILL cannot be assigned to thermistor number 7. The factory installs this seven thermistor
assembly all the way to the floor of the sensor tube, which positions thermistor number 1 one inch above the
floor (i.e.; the first thermistor is offset from the floor zero inches).
If you would like to stop the fill at a depth greater than seven inches from the floor, the sensor
assembly must physically be raised inside the sensor tube. The distance that it has been raised
becomes the new OFFSET and the controller must be notified of this offset from the floor. The
factory settings are START FILL at 3 inches and STOP FILL at 5 inches, with an OFFSET of zero. If
you want to establish a START at 15 and STOP at 17, raise the sensor assembly 12 inches
(17 minus 5) and set the controller OFFSET to 12 by: Selecting MENU, LEVEL SENSING, SET
SENSOR OFFSET. The unit should begin filling. The EX-LOW LEVEL sensor has been subjected
to the gaseous condition and should sound an alarm (O.K. to MUTE). Note that in this scenario, you
have directed your LN2 supply to accomplish a 15 inch fill level. It may be necessary to stop the fill
manually and allow the supply vessel time to regain enough pressure to complete
this exceptionally long initial fill.
Power Failure Alarm
If power is interrupted, a note of the time and duration will be recorded in the log. No local alarm will be
sounded unless a high temperature is detected after power resumes. The Remote Alarm will be triggered
anytime the power is interrupted.