Emerson Rosemount Analytical OPM 4000, Инструкция по эксплуатации

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Instruction Manual
IM-105-4000, Rev 1.3
October 2008
1-5
OPM 4000
OPM 4000 System
Features
Transmissometer/Retro Reflector
The OPM 4000 is a precision, double-pass, dual beam transmissometer that
consists of a transceiver (transmitter/receiver) mounted on one side of a stack
or duct and a passive reflector mounted on the opposite side. The light
source, photo detectors and all measurement/reference optics used in opacity
measurement are housed in the transceiver.
The function of the reflector is to return the measurement beam to the
detector in the transceiver, creating a double pass across the process stream.
The standard reflector is used for measurement path lengths up to 15 feet
(4,6 m). For longer path lengths, maximum 60 feet (18,3 m), reflectors, optical
parts and electronics will vary.
Control Unit
Mounted in a control room environment, the OPM 4000 control unit provides
instrument control functions, opacity readings, alarms and fault indicators,
analog outputs, and diagnostics with contact closures.
Service Module
The service module is used to pass signals to and from the transceiver and
control unit, display opacity via digital meter, initiate maintenance zero and
span cycles and insertion of external current meter in the transceiver to
control unit 4-20 mA loop.
Optional Air Purge Weather Cover System
The transceiver and reflector may be mounted in weather covers. The
weather covers are fairly compact to allow movement around them even on a
three-foot walkway or platform. They protect the stack-mounted components
from dirt, moisture, stack temperatures within the specified ambient
temperature limits, and errant air currents around the stack.
The air purge system constantly circulates air past the optical window. The
airflow is directed through the hose to an air plenum on the stack side of the
optical window. The airflow in the air plenum area results in reduced pressure
and increased velocity. This venturi effect tends to continually draw the air
around the optical window into the purge air stream, thereby keeping the lens
clean for long periods.
Alignment System
The OPM 4000 includes a built-in through-the-lens alignment system. The
alignment target can be viewed through a window on the transceiver.
Adjustments to changes in alignment are provided by a 3-point alignment
system, which is integral to the air plenum.
Cabling
The standard cabling used between the stack-mounted units and the control
unit is at a minimum 6-pair, #20 AWG, twisted, shielded cable. More pairs or
larger than 20 AWG is acceptable.