Transmitter for NH 3 CI 21 Operation Manual

Transcription

1 Transmitter for NH 3 CI 21 Operation Manual

2 Content Page For your Safety 3 General Description 3 Detection Principle 3 Operational Notes 4 Design 4 Mounting Position 5 Mounting 5 Installation of Electrical Connections 6 Putting into Operation 6 Check of Electrical Zero Point 7 Check of Sensitivity (Calibration) / bump test 7 Check of Zero Point (Dead Band) 7 Trouble Shooting 8 Service 8 Service Address 8 Maintenance and Inspection 9 Spare Parts 9 Accessories 9 Connection Diagram CI 21 Built-in Sensor 10 Connection Diagram CI 21 External Sensor 11 Technical Data 12 2

3 TYPELABEL I NS I D E M E N U C H A N N E L O N F A UL T % For your Safety As with any piece of complex equipment, the GfG transmitter CI21 will do the job designed to do, only, if it is used and serviced in accordance with the manufacturer's instructions. Please protect yourself and your employees by following them. All individuals who have or will have the responsibility for using and servicing this product must carefully read this manual. The warranties made by GfG with respect to the product are voided, if the adjustment of functions or parameters is changed without the permission of GfG. They are also voided, if the product is not used and serviced in accordance with the instructions in this manual. Failures or false alarms caused by interfering gases or electrical signals are not part of the warranty obligation. The above does not alter any statements by GfG regarding warranties, conditions of sale and or delivery. General Description A fixed gas monitoring system consists of the transmitter (MWG) and a controller (GMA), which are connected by means of cable. The transmitter converts the unit for the gas concentration into an electrical signal and transmits it over the cable to the controller. Fixed Gas Detection System AMMONIA ou N A3 nm A2 A1 U A 3 A 2 A 1 FA UL T U TEST MENU QU T MENU Detection Evaluation Warning Fig. 1 The CI21 is an "intelligent" transmitter. The comprehensive electronics allows easy operation and maintenance and also increases the operational safety and accuracy. The following features characterize the CI21: Easy calibration at site. Compensation of temperature effects. Long sensor life. Detection Principle The CI21 is operated with a Charge Carrier Injection sensor. As long as there is no gas in the ambient air, the internal resistance of the sensor is rather high. As soon as NH 3 (Ammonia) is adsorbed at the sensor surface, the internal resistance is reduced. The change in resistance is the measure for the gas concentration and is converted into a standardized current signal ( ma or ma) by the integrated electronics. The Charge Carrier Injection sensor has a proven long-term stability, and selectivity. 3

4 Operational Notes The CI21 passes function and performance tests before shipment and is calibrated with suitable test gases. This does not overrule the need to perform another function test after putting the transmitter in operation. Design The design of the CI21 is shown in fig. 2. The sensor is mounted in the sensor support (pos. 5). The gas enters the sensor chamber through the diffusion inlet (pos. 6). The electronics convert the measurement signal into the output of ma or ma that is supplied to the controller by means of cable. CI21 Design 1. Casing top 2. Casing bottom 3. Type label 4. EMC cable gland (PG 11) 5. Sensor support 6. Diffusion inlet Fig. 2 Poti A Poti 0 Poti C Test Contacts Jumper Epoxy Resin Fuse Terminals EMC - PG 11 Sensor Fig. 3 / Schematic 4

5 Mounting Position It is essential to know the ambient conditions, which have to be taken into consideration before deciding on the mounting position. To achieve representative measurement results, take care of: the room ventilation, the gas density, and the danger highlights. Install the CI21 at a place where the gases pass the sensor even in case of bad ventilation. If necessary, use a smoke cartridge to check. Furthermore, take the following into consideration as well: Ambient temperature, Rain water, hose water, dripping water, condensation and Dust in the atmosphere. The CI21 is to a great extent protected against the entering of water and dust (IP 54). Special accessories are available to provide additional protection for very difficult conditions. Please contact GfG for detailed information.! Warranty may be voided, if the transmitter is exposed to ambient conditions that were unknown to GfG during planning, production or delivery. When deciding on the position for the transmitter, make sure that it is always accessible for service and maintenance. It is recommended to mount the CI21 with the sensor facing down to the floor. A different mounting position, however, does not affect the sensor accuracy. Mounting For connecting the CI21 refer to the connection diagram (also refer to the terminal diagram of your GMA controller). For mounting the transmitter remove the four lock screws and lift the casing top off. Fix the casing by means of two screws through the relevant borings.! The CI21 is not certified for use in hazardous areas 5

6 Installation of Electrical Connections An electrician obeying the applicable regulations should do procurement of cable and electrical connections. A shielded 18/3 cable should be used (Belden #8770 or equivalent) for distances less the 500 yards. Note: Shielding is effected over the EMC cable screwing. Terminals Resin Terminals Resin red red green yellow Signall Ground Voltage Supply EMC-PG 11 green brown white blue Signall Ground Voltage Supply EMC-PG 11 Sensor Sensor Sensor Connecting Wire, max. 2 m External Sensor Fig. 4 The supply voltage for the transmitter (terminal 4) is V DC. Once the installation is completed, close the casing top and fix it with the screws. Putting into Operation Once the CI21 is installed, a skilled person can put it into operation. Before shipment, the CI21 has been calibrated and tested after a specific warm-up time for several days. When connecting to a controller (power supply) you should allow approx. 60 minutes to warm-up the Charge Carrier Injection sensor before checking the sensitivity. Should you notice that a re-calibration is required, allow an extended warm up period of about 4 hours. In case you replace the sensor, adjust the jumper of the transmitter according to the specification on the new sensor. (Sensor replacement requires adjusting the dead band for the new sensor) The CI21 is calibrated and tested before shipment. Certain deviations, however, are possible due to transport, mounting and ambient conditions. Inside the CI21 there are two test contacts to check the electrical output signal (fig. 3). The voltage at the test contacts can be measured with a voltmeter. Warm-up time is approx. 60 minutes. Poti A Poti 0 Poti C Jumper Test Contacts Epoxy Resin Fuse Terminals EMC - PG 11 Sensor Fig 3 6

7 Check of Electrical Zero Point 1) Use a multimeter to check the output signal by measuring the voltage at the test contacts. 2) The reading should be in the range of: V Pot 0 Test Contacts V 3) In case of deviation it is possible to re-adjust the value by turning potentiometer O Sensor Check of Sensitivity (Calibration) / bump test 1) Use a multimeter to check the output signal by measuring the voltage at the test contacts. 2) Attach the calibration adapter to the diffusion inlet of the transmitter. Then select a suitable test gas (200, 1000 or 10,000ppm NH3 depending on the detection range) Pot C Test Contacts 1.00 V 3) Allow a flow of 0.5LPM or 1CFH for 3-5 minutes before reading and adjustments. 4) The reading should be in the range of 1.00V +/- 10% Sensor 5) In case of deviation you can correct the value by turning potentiometer C. When using a GMA controller signal checks and adjustments may be done at the GMA (please reference GMA manual).! Do not use a test gas with a balance of nitrogen. Calibration gas must be GfG approved. Check of Zero Point (Dead Band) Adjustment to the zero point (Pot A) should not be done without direct instruction from GfG. 1) Use a multimeter to check the output signal by measuring the voltage at the test contacts. 2) Attach the calibration adapter to the diffusion inlet of the transmitter. Then select a suitable test gas (20 or 30 ppm NH 3 depending on the detection range). 3) Allow a flow of 0.5LPM or 1CFH for 3-5 minutes before reading and adjustments. 4) The signal should be approx V. Pot A Sensor Test Contacts V 5) In case of deviation it is possible to re-adjust the value by turning potentiometer A. Potentiometer A is factory set and should not be adjusted without direct instruction or training from GfG. 7

8 Trouble Shooting CI 21 Troubleshooting Symptom Reason/s Solution 0 ma output current incorrect wiring verify wiring to CI 21 diagram defective fuse replace fuse cut cable/wire reconnect wiring dc voltage too high correct voltage to vdc defective electronics contact GFG MFG. for instructions no reaction to test gas improper gas use GFG approved test gas faulty sensor replace sensor Controller shows incorrect reading with test gas applied. controller not calibrated calibrate controller CI 21 out of calibration calibrate CI 21 High output current with no gas present. open ground wire reconnect ground wire possible interfering background gas identify background gas and eliminate Slow sensor response incorrect test gas use GFG approved test gas humidifier sponge too wet wring out sponge humidifier sponge too dry moisten sponge sensor defective replace sensor Service Service includes maintenance, inspection and repair of gas warning equipment and function checks. A function check includes: Check with alarm gas concentration Check of zero point and sensitivity (calibration) Check of response time Check of gas sampling and gas processing system (if any) Check of alarm signal activation Check of failure alarm The function check should be done before putting the system into operation, and it should be repeated at least once a year. Service Address For additional questions on the product or in case of failure and problems please contact: GfG Instrumentation, Inc Oak Valley Drive Suite 20 Ann Arbor, Mi Phone: Fax: info@gfg-inc.com Web: 8

9 Maintenance and Inspection With maintenance and inspection the proper and planned status of the gas detection system is controlled. The CI 21 does not require special maintenance. Depending on the ambient conditions, gas detection systems may show a different behavior. Therefore, it is important to perform a visual check every day, particularly during the first few days after putting into operation. Check of pump assembly and gas processing system (if any). Check of gas supply for soiling (for correct measurement the gas supply to the sensor must not be blocked). Sensors are subject to ageing and exhausting processes. Depending on their type and on their exposure to gas they are more or less used. A sensitivity check can only be done with a suitable test gas after certain periods of time. The sensitivity calibration is an expert calibration and is usually performed by GfG service or by authorized persons. Spare Parts Part No. Spare Sensor/built-in Spare Sensor/external In case you replace the sensor, adjust the jumper inside the transmitter according to the specification on the new sensor. (Sensor replacement requires adjusting the dead band for the new sensor) Accessories Part No. Calibration Adapter Calibration Kit w/o Gas (fixed flow regulator, tubing, inline humidifier & adapter) Calibration gas (200ppm NH3 balance air) Calibration gas (1000ppm NH3 balance air) Calibration gas (10,000ppm NH3 balance air) Calibration Kit with gas (10,000 ppm) Calibration Kit with gas (1,000 ppm) Calibration Kit with gas (200 ppm)

10 Connection Diagram CI 21 Built-in Sensor Built-in Sensor MK red red green yellow white green brown Connect shield to Cable Gland Signal ma GND 20V / 24V GMA GMA motherboard post 1997 (blue) GMA motherboard pre 1996 (no color) GMA GMA GMA81 (A)

11 Connection Diagram CI 21 External Sensor MK External Sensor green brown white blue white green brown Connect shield to Cable Gland Signal ma GND 20V / 24V GMA GMA motherboard post 1997 (blue) GMA motherboard pre 1996 (no color) GMA GMA GMA81 (A)

12 Technical Data Transmitter CI21 Type: Sensor Type: CI21 MK (external) or MK (built-in) Gas: Ammonia, NH 3 Standard range: 200ppm, 1,000ppm or 10,000ppm Gas Supply: Diffusion Detection Principle: Charge Carrier Injection (CI) Supply Voltage: V DC Output Current: mA (4kΩ) or mA (200Ω) Response Time t A : < 8 s Typical Sensor Life: > 2 years Climate Conditions Casing Temperature: C ( F) Humidity: 0 99 % r. h., non condensing Pressure: hpa Material: Aluminum Protection: IP 54 Cable Gland: ½ in. conduit Transmitter Cable: 3 core shielded cable AWG 18 for runs less than 500 yards Belden #8770 or equivalent Dimensions: 100 x 100 x 57 mm (WxHxD) Weight: approx. 370 g 12

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16 1194 Oak Valley Drive, Suite 20 Ann Arbor, Michigan United States of America Phone: (800) or (734) Fax (734) Website: GfG reserves the right of modification JA 7004-C21