Det-Tronics Eagle Quantum 95-8470-05, Инструкция по эксплуатации

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VII-22
EQ2200DCU DIGITAL COMMUNICATION UNIT USED
WITH DET-TRONICS H
2
S/O
2
SENSORS OR OTHER
TWO-WIRE 4 TO 20 MA DEVICES
Determine the best mounting locations for the detectors.
Whenever practical, detectors should be placed where
they are easily accessible for calibration.
WARNING
Do not apply power to the system with the cover
removed unless the area has been verified to be
free of combustible gases or vapors.
The DCU utilizes the following:
1. A terminal wiring board mounted at the bottom of
the junction box.
2. A communication module mounted above the
terminal wiring board using the standoffs provided.
See Figure VII-33.
Assembly and Wiring Procedure
Attach the sensor to the DCU enclosure. Do not over-
tighten. If a sensor separation kit is being used, attach
the sensor to the separation kit junction box and wire
the device as described in the “Sensor Separation”
section.
CAUTION
The sensor threads can be coated with an
appropriate grease to ease installation. Also
lubricate the cover threads. (See “Ordering
Information” for part number).
Connect the external wiring to the appropriate terminals
on the DCU terminal wiring board. Refer to Figure VII-
34 for terminal identification. See Figure VII-35 for an
example of a Det-Tronics electrochemical sensor
connected to a DCU.
Attach the communication module to the standoffs as
shown in Figure VII-33. Connect the ribbon cable from
the terminal wiring board to the communication module.
Set the address for the device. Refer to “Device
Address Switch Setting” in the “Switch Setting” section
of this manual for complete information regarding the
switch setting procedure.
Check the wiring to ensure proper connections, then
pour the conduit seals and allow them to dry (if conduit
is being used).
NOTE
Before placing the cover back on the enclosure
following completion of assembly and wiring,
inspect the enclosure O-ring to be sure that it is in
good condition and properly installed. Lubricate
the O-ring and the threads of the cover with a thin
coat of an appropriate grease to ease installation.
Refer to the “Ordering Information” section for the
part number of the recommended grease
(available from Detector Electronics). If the
installation uses catalytic type combustible gas
sensors, it is imperative that lubricants containing
silicone NOT be used, since they will cause
irreversible damage to the sensor. Place the cover
on the enclosure. Tighten only until snug. Do not
over tighten.
SENSOR SEPARATION FOR DCU WITH H
2
S AND O
2
SENSORS
Since the transmitter for the electrochemical sensor is
already mounted within the sensor housing, simply
mount the entire sensor assembly to the sensor
separation kit junction box and wire it to terminals 2 and
4 inside the DCU, the same as a regular (without sensor
separation) installation. Connect the shield to the
ground terminal in the DCU junction box.
Refer to Table VII-8 for separation distance limitations
for H
2
S and O
2
sensors.
A1571
COMMUNICATION MODULE
STANDOFFS (4)
TERMINAL WIRING BOARD
Figure VII–33—Printed Circuit Boards in Universal DCU