Thermo 4862, Руководство по эксплуатации и техническому обслуживанию

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SECTION 11 - SPECIFICATIONS OF
ROTATION ALARM SYSTEM (SEE FIG. F)
1. Rotation Failure Detection Method:
Magnetic Reed Switch
Four magnetic reed switches are located at the farthest
end of the main drive belt train, two for each half of the
roller rack. Magnets embedded into plastic pulleys close
the magnetic reed switches as they pass during normal
rotation.
2. Time between rotation failure and user notification:
3 minutes
The Rotation Alarm System will notify the user of a
rotation failure within three minutes of the occurrence.
3. Rotation Alarm indicators:
a. Front Panel light indicators:
Three LED indicators located on the front panel
will flash at approximately a 1-second rate during
an alarm condition. LED indicators are ON in nor-
mal operation.
b. +12V DC output:
A +12V DC signal is available at the front panel
interface jack on pins 2 (+12V) and 4 (GND).
During alarm condition, the +12V signal switches
ON/OFF at a rate of approximately 1 second.
During normal operation, the +12V signal is steady
ON. The +12V DC output can source 25ma of cur-
rent.
c. Dry contacts:
A set of dry contacts are available at the front panel
interface jack on pins 1 and 3. Contacts are
CLOSED constant in alarm condition and OPEN
constant in normal condition. Contact ratings are
0.5 amp at 24VDC and 0.25 amps at 11 5VAC.
d. Audible Alarm:
An Audible alarm tone of 2700Hz, ±500Hz will
cycle on/off at approximately a 1 second rate dur-
ing an alarm condition.
4. User interface:
4 pin MIC jack.
A 4 pin male MIC jack socket is located on the front
panel of the roller apparatus for user interface of the
Rotation Alarm System.
SECTION 12 - INTRODUCTION TO
ROTATION ALARM SYSTEM
The Wheaton Rotation Alarm System is a factory or retro-
fitable option to monitor a roller apparatus for operation.
Magnetic sensors located in the main drive train detect the
passing of magnets embedded into the plastic pulleys of the
drive system. If a magnet fails to pass a sensor within 3 min-
utes, the Rotation Alarm System will activate and flash the
front panel LED indicators with an audible alarm. The system
sends a p12VDC signal and closes a set of dry contacts.
12.1 CIRCUIT OPERATION PRINCIPLE
The Rotation Alarm System uses four magnetic reed
switches located in the main drive train on the last deck (fur-
thest deck from the drive motor) to monitor rotation. In this
way, any belt breakage between the drive motor and the last
deck will be detected. Magnets embedded in the plastic pulleys
beneath the reed switches pass by the reed switch sensors dur-
ing normal operation. As the magnets pass by, the reed switch
closes, sending a signal back to the Rotation Alarm circuit
board located in the roller apparatus control housing.
Four independent timer circuits on the Rotation Alarm cir-
cuit board monitor each magnetic reed switch. As the embedded
magnet passes each magnetic reed switch, each of the four
timer circuits are reset to begin a new three minute timing peri-
od.
If any of the magnetic reed switches fails to reset its
respective timer circuit within the 3 minute timing period, that
timer circuit will send a signal to put the Rotation Alarm circuit
board into Alarm mode.
In Alarm mode, the circuit board will begin flashing the
front panel LED indicators with an audible alarm. The system
closes a set of dry contacts and sends a pul12VDC sig-
nal from the front panel remote annunciation jack.
Model 4862 Cell Roller____________________________________________________Rotation System Alarms / Introduction
12-1