Smoke Opacity Monitor

The Preferred Instruments JC-30D Smoke Opacity Monitoring System assures an accurate measurement of the smoke emissions from boilers, incinerators, kilns, and similar sources of intermittent, visible emissions. The system provides a continuous opacity readout, alarm indication and shutdown capability.

Automatic Calibration when Burner Cycles off

• The JC-30D includes a 120 Vac input that monitors the burner fan starter coil and initiates an Automatic Calibration cycle whenever the burner fan stops running (ensuring a clear stack condition).  This prevents nuisance burner trips due to dust build-up
• “WARNING: CLEAN LENSES NOW” is displayed when the dust level is high
• At the completion of the Calibration Cycle, the JC-30D turns off the light source until the fan re-starts, extending the life of the bulb
• A Calibration Cycle can be manually initiated from the JC-30D Menu

Early Warning Message and Relay Contact

• Deteriorating combustion conditions can be detected early before developing into major problems

Burner Safety Shutdown Message and Relay Contact

• Dangerously high opacity is an indication of an unstable flame condition

Optical Sensing Assembly

• The Optical Sensing Assembly consists of a Light Source and Light Sensor
• These units are mounted on opposite sides of the smoke duct with the light beam focused from the source side to the sensor side
• This reliable single pass design requires no moving parts or complicated optical devices
• Lenses are specially designed for easy cleaning without dismantling the installed assembly

Three Alarm Sequences (field selectable)

• Standard – This is the most used sequence with a 20 seconds “smoke-puff” delay and a 120 seconds (adjustable) shutdown relay.
• NYC BAR – This sequence is similar to the Standard Sequence, but conforms to the New York City D.E.P. Bureau of Air Resources requirements.
• Wood / Coal Overfire Air Fan – This sequence is used with stoker fired boilers

Flexible Communications for Data Logging

• 4-20 mAdc Opacity Re-transmission
• RS485 Modbus Interface

The Optical Sensing Assembly consists of a Light Source and Light Sensor. This reliable single pass design requires no moving parts or complicated optical devices. The following are the sensor's operationg sequence:

• Units are mounted on opposite sides of the smoke duct with the light beam focused from the source side to the sensor side
• Smoke passing through the light beam reduces the intensity being received by the sensor
• A signal is transmitted to the indicating instrument which continuously displays the percent smoke opacity and provides the alarm and control function

Panel
Power Supply: Case Size: Enclosure Type: Ambient Temp.: Digital: Status Messages: Alarm Setpoints:	120Vac 50/60Hz, 15VA 8"H x 3.5"W x 7.5"D NEMA 4 faceplate, Flush Mounting +32° to +122° F ambient High Contrast LCD Display, 4" high, 0.5% Resolution Bargraph ALARM, SHUTDOWN, WARNING: CLEAN LENSES NOW, EXCESS LIGHT Adjustable 5-50%
Light Source and Light Sensor
Calibration: Spectral Response: Angle of Projection: Operational Error: Span Drift: Zero Drift: Calibration Error: Response Time: Sighting Distance: Wiring Distance: Sensor Housing:	Automatic, Off-Line Photopic Peak and mean within 500-600nm <5° <5% <2% <2% <1% (Linearity) <10 seconds for 95% change in opacity 1 to 8 foot smoke duct, 3 to 10 foot optical path length 500 ft. max (16 ga. wire), 250 ft. max (20 ga. wire) ¾" pipe mount
Outputs
Relay Outputs: Output: Network Output:	Two SPDT Relays, 10 A resistive, 8 FLA, ½ HP, 120 Vac Retransmission 4-20 mAdc, 650 ohm load max 1200-38400 baud, RS485 Modbus, ASCII or RTU

Ordering Information

1. JC-30D includes Monitor, 190711 Light Source and 190712 Light Sensor

Optional Accessories

1. Pressure cap set with purge and non-purge fittings (107226P)
2. Pressure cap set with integral blower (2 blowers) (190275A)
3. Light Sensor shield (for installations with high ambient light levels) (190713)
4. Remote audible / visual alarm (SDA-VB)
5. Alarm  bell, 6" dia., 85 dB (SDA-B6)
6. Recorder-31 day, 2 ¼" strip chart (R88-E5)