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How many points can I
monitor and how are they displayed? |
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Up to 255 points can be monitored
from a single PC. If any microprocessor in the communications loop
is removed for maintenance, that unit is automatically bypassed, maintaining
the integrity of the communications loop. The PC will simply display
a "No Response" message for that microprocessor. The total
cable length between each unit can stretch as far as 2 miles (3.2k). |
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What monitoring technique
does the unit employ? |
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The CPM 5000 series measures particle
flow with a beam of visible light through which the particles travel.
The movement of particles through this beam causes a rapid variation
in the received light intensity. This variation is expressed as a
percentage of the average light received. This measurement technique
allows for a direct calibration to particle concentration. Because
emissions are a percentage of the received light, they are virtually
unaffected by dirty or misaligned optics, or a failing light source
or detector. |
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How do you setup the analyzer? |
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When power is first applied to
the CPM 5000 series, the window value is automatically set to the
highest possible value. The window value is an indication of the average
light intensity received from the transmitter. The window value provides
an indication of dirty or misaligned optics, or an aging light source
or detector. Since the emissions reading is automatically compensated
for these faults, the actual window value number is not critical as
long as there is sufficient received light for reliable operation.
Trending of the window value, however, provides a convenient method
for predicting maintenance. |
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How is the system configured? |
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The window value setting is the
basic calibration of the CPM 5000 series and is performed automatically.
Setting the window value involves adjusting the gains of the microprocessor
so that the detection circuits have the highest possible signal. This
significantly reduces the signal to noise ratio. The window value
is automatically set at initial power-up. This may also occur if dirty
optics were cleaned, or the transmitter and receiver head were realigned.
In addition, the CPM 5000 series can be programmed to automatically
set the window value at any time using either the keypad or one of
the communications ports. |
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What effect does ambient
light create? |
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The presence of ambient light can
interfere with the light emitted from the transmitter head. Sunlight
shining into a stack is an example of ambient light. The CPM 5000
series can automatically compensate for the presence of ambient light
by programming the instrument to detect it. If the monitor is programmed
to detect ambient light, the transmitter light source (LED) will automatically
be modulated to measure the ambient light. All measured values will
then be compensated for the presence of ambient light. This is a software
option available in the profile setup. |
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Does the analyzer store
data? |
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In addition to the trending provided
by the remote PC (operator interface), the CPM 5000 series provides
one month of on-board trending. Readings are recorded every six minutes
of operation, and are averaged . The available data includes date,
time, emissions, window value, motherboard temperature, transmitter
temperature, and receiver temperature. The trended data can be viewed
on the LCD display, or can be retrieved at any time through the local
or remote communications port. This provides a backup for the remote
PC, therefore, no data is lost. |
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What duct width can the
system monitor? |
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For applications with ducts which
are 30 ft. (9.14 m) in diameter and less, a CPM 5000 series transmitter
with an LED light source will be provided. The LED light source is
collimated so there is minimal loss of light over long distances.
The LED light source has a wavelength of 660 nm, a mean time to failure
of 10,000 hours, and can be modulated in order to detect the presence
of ambient light. |
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Is alignment critical? |
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The diameter of the receiving optics
used in the CPM 5000 series is 50 mm. This is approximately twice
the diameter of the light beam emitted from the transmitter. This
provides a larger target for the transmitter, and therefore, greater
tolerance in the alignment of the transmitter and receiver heads.
The gain of the receiver head is factory adjusted to match the type
of light source being used at the transmitter. |
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Is purging of the heads
required? |
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The CPM 5000 series transmitter
and receiver heads are each equipped with a built-in continuous purge
air system. This system provides positive air pressure in front of
the viewing optics. This system aids in the prevention of material
accumulation on the transmitter and receiver optics, which significantly
reduces maintenance. In addition, the purge air system provides cooling
of the transmitter and receiver heads. |
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Is temperature of the
sensor heads critical? |
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The transmitter and receiver heads
are each equipped with a solid state temperature sensor. This provides
for the temperature of each head to be continuously monitored by the
microprocessor controller and in turn, by a remote PC. An alarm is
generated if either head becomes too hot. This is typically used to
indicate the loss of the purge air system. |
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Does the analyzer have
a local display? |
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The microprocessor controller has
an optional four-line, 40 character, back-lit LCD display. Since LCD
displays require light to be seen, back lighting provides for operation
even in low light conditions. This display provides for displaying
letters, numbers, and graphics. All CPM 5000 series status, alarm,
or operational messages are displayed in English; codes are not used.
For future expansion, or as features are added, display screens can
be modified or added. |
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Does the display have
graphic capabilities? |
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The real time analog values are
displayed both as a real time digital display and as an analog bar
graph, providing a very user friendly display which illustrates rapidly
changing data. This is most useful for observing emission spikes. |
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What about system security? |
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There are two levels of security
in the CPM 5000 series. To access each level, three digits of a six
digit security code are required. |
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Are there HELP screens
available for in-field questions? |
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The CPM 5000 series provides a
selection of help screens. These text screens provide the operator
an on-board manual for operating and troubleshooting. In addition,
all alarm conditions are explained with suggested remedies. Use of
the help screens does not interrupt operation of the microprocessor. |
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How do you communicate
with the analyzer? |
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Each unit of the CPM 5000 series
has a remote communications port for the connection of the remote
PC. This port is selected by a local/remote switch mounted on the
microprocessor controller PC board. Each monitor also has a local
communications port for the connection of a local PC. A notebook or
laptop computer is often used for this application. Both ports provide
the capability to control the CPM, read and save the present profile,
or download a new profile. |
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What if the system has
a problem, does a technician need to visit the site? |
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The remote PC provided with the
CPM 5000 series includes Windows®-based System Monitoring Software™
that allows you to monitor all points at the touch of a button. The
PC also includes an internal modem for Remote Diagnostics capability
by BHA personnel. Remote Diagnostics allows observation or service
of the CPM 5000 series without sending a field service engineer to
your plant. All information is available via modem and each setting
of the unit can be adjusted allowing for remote calibration. The real
time and historically trended data can be viewed and new software
can be uploaded. Also, this data can be used remotely to assist in
troubleshooting your entire air pollution control system. |
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What software alarms are
available? |
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The CPM 5000 series provides six software alarms and each will
be displayed on the LCD display. The six software alarms are as
follows:
- High Emissions Alarm: This alarm alerts an operator to an unacceptably
high level of emissions.
- Warning Alarm: This alarm provides an early warning of increasing
emissions.
- Low Window Value Alarm: This alarm indicates that there is
insufficient received light for reliable operation, indicating
the need to reset the window value, clean the optics, or align
the transmitter and receiver.
- Motherboard High Temp Alarm: This alarm indicates that the
temperature of the microprocessor circuitry is unacceptably high.
- Transmitter and Receiver High Temp Alarms: These alarms indicate
that the temperature of the transmitter or receiver head is unacceptably
high. This is most often an indication of a loss of the purge
air system.
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What hardware alarms are
available? |
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External indication of alarms such as a light, bell, or other signaling
devices are available for these four hardware alarms:
- High Emissions Alarm Relay: This relay closes to alert an operator
to an unacceptably high level of emissions.
- Warning Alarm Relay: This relay closes to provide an early warning
of increasing emissions.
- Maintenance Alarm Relay: This relay closes to indicate that
there is a pending low window value or high temperature alarm.
- Test Mode Relay: This relay closes to indicate that the window
value is being automatically set or the CPM 5000 is in the LED
Self Test mode.
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Can the CPM 5000 series
measure other dust collector parameters? |
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The CPM 5000 series has two analog
inputs available for the connection and monitoring of earlier model
Continuous Particulate Monitors, differential pressure and gas stream
temperature or any instrument with a 4-20 mA readout. These inputs
are not isolated from ground, and have a range of 0 to 5 volts. Analog
data series at these inputs are displayed by the CPM 5000, and are
trended and displayed by the remote PC. |
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What safety methods are
built-in to the system? |
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The power switch used on the CPM
5000 series provides for both sides of the power line to be disconnected
when the breaker switch is in the off (down) position. In addition,
the breaker switch provides overload protection and is rated at 6
amperes. |
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Can the CPM 5000 series
survive in my plant environment? |
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The CPM 5000 series is built using the IPC-A-610B, Class 3 specifications
for high performance electronic products. This specification is
intended for products that must offer continued performance, often
in uncommonly harsh environments. The sockets for the integrated
circuits used are of a machined pin design. This prevents the integrated
circuits from becoming loose in the socket and not making a connection,
due to vibration and temperature cycling. All components receive
a 100 hour burn-in and functional test before shipment. Each circuit
board is conformal coated with a clear coating. This coating dissolves
when touched with a soldering iron. This protects the circuit board
from attack by environmental hazards found in the industrial environment.
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