Introduction. Refrigerant Leak Detecting System. Feature and Benefits

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1 PSC European Refrigeration Controls Catalogue Catalog Section 9 Product Bulletin PD-GAS-E Refrigerant Leak Detecting System Introduction This range of refrigerant leak detecting systems is designed for permanent installation. They monitor refrigerant leakage on a continuous basis. It provides a valuable warning before refrigerant leaks impair system efficiency and running costs and, over time, prevents major refrigerant loss. Refrigerant wastage and replenishment are both economical and environmentally unacceptable. The refrigerant leak detecting system consists of: A refrigerant detector. This detector senses refrigerant leakage and can be used as a stand-alone device or can be connected to a monitoring unit. Various detectors for different refrigerants are available. Refrigerant Leak Detecting System A monitoring unit. The monitoring unit shows the status of one or more remote detectors. A wall mount or a DIN rail mount model is available. Feature and Benefits! Two alarm thresholds Pre-alarm signalling before an alarm is activated! No on-site calibration necessary Easy installation.! Semi-conductive sensing element Long lifetime and long-time stability! Alarm memory on detector Possibility to memorise too high refrigerant concentration! Selectable auto reset or Auto reset or manual reset is field selectable manual reset mode on monitoring unit! Up to 10 detectors can be connected to one monitoring unit Multiple detectors can be monitored by one unit. Makes future expansion very easy Johnson Controls Inc. Catalogue Section 9

2 2 Leak Detecting System Refrigerant detector Description Each detector can work as a stand-alone unit, or can be connected to a monitoring unit for remote monitoring. (See page 4 and 5) The detector has 2 relay outputs. The prealarm relay contact is closed when the refrigerant concentration exceeds the prealarm level, giving a pre-alarm signalling. When the concentration exceeds the alarm level, the alarm relay is activated. LED s indicate the status of the detector, such as: Power-on, Detector active, Alarm, and Alarm memory. Each detector is refrigerant specific. (See selection table on next page and the application table on page 9). Three different detector enclosures are available: Room version (GD2.0 type); Splashproof version (GS2.0 type) and Safety valve version (GR2.0 type). The detectors are delivered for a specific refrigerant. Field calibrations are normally not necessary. (See factory adjusted detection levels at page 9). Functioning (See layout drawing and drawing relay functioning ) If the power supply is switched on the green LED will light up to indicate power on. After 4 minutes a yellow LED will light to indicate detector active. The detector is now ready to sense refrigerant leakage. If the detected concentration of refrigerant, exceeds the pre-alarm level, the pre-alarm relay is activated (terminals 5 and 6) and the LED Alarm is lighted up. If the refrigerant concentration increases further and exceeds the alarm level, than the alarm relay is activated (terminals 7 and 8). If the concentration decreases, the relays will switch off, first the alarm relay, then the prealarm relay. The pre-alarm or alarm condition will be memorised by LED Alarm memory. This LED can be reset by pressing the reset button under the cover. Note: It is only possible to reset the alarm memory if the refrigerant concentration is below the pre-alarm level. Skip the alarm memory function by removing Jumper BY2. Fig. 1 Detectors GS2.0/GD2.0/GR2.0! Note The detector has a limited range to detect different types of refrigerants. It is important to check the presence of other gases that may cause an alarm. Such as: Gasoline, cigarette smoke, liquid cleanings, solvents, hydrogen from loading batteries, etc. It is recommended to test the system twice a year. See page 8 for check and calibration instructions.! Note The relay contacts should be powered by max. 24 V ac/dc. Fig. 2 Relay Function Catalogue Section Johnson Controls Inc.

3 Leak Detecting System 3 Layout Fig. 3 Wiring Diagram Fig. 4 Selection table Item code Refrigerant Enclosure type GD2.0-CFC CFC/HCFC universal Room, fig 12a GD2.0-HFC HFC universal Room, fig 12a GD2.0-NH3 Ammonia Room, fig 12a GS2.0-CFC CFC/HCFC universal Splash proof, fig 12b GS2.0-HFC HFC universal Splash proof, fig 12b GS2.0-NH3 Ammonia Splash proof, fig 12b GR2.0-CFC CFC/HCFC universal Safety valves, fig 12c GR2.0-HFC HFC universal Safety valves, fig 12c GR2.0-NH3 Ammonia Safety valves, fig 12c Note: See application table on page 9 and dimension drawings on page 10, Johnson Controls Inc. Catalogue Section 9

4 4 Leak Detecting System Monitoring units Description The Monitoring unit shows the status of one or more refrigerant detectors (See page 3 and 4). When the refrigerant concentration as measured by the detector exceeds the prealarm level, the Pre-alarm relay on the unit is activated, giving a pre-alarm. When the measured concentration exceeds the alarm level, the Alarm relay on the unit is activated. The Fault relay is energised when there is a detector or power supply failure. LED s indicate the status of the unit, such as: Power-on, Detector active, Pre-alarm, Alarm, and Fault. Two models are available, a 35 mm DIN rail version (G27C) and a wall mount version (G230C). Fig. 5 Monitoring Units, G27C/G230C Functioning If the power supply is switched on the green LED will light up to indicate power on. After 4 minutes a yellow LED will light up to indicate the unit is active. The unit is ready now to monitor the refrigerant detector(s). If the concentration of refrigerant, measured by the detector, exceeds the pre-alarm level, the pre-alarm relay is activated and the LED Pre-alarm is lighted up. If the refrigerant concentration increases further and exceeds the Alarm level, than the Alarm relay is activated. When the refrigeration concentration decreases the relays can be reset by pushing the Reset button in front of the cover. Note: It is only possible to reset the relays when the refrigerant concentration is low enough. Both models have the possibility to set the operation mode from manual to automatic reset. Model G230C has an additional buzzer build in which gives an audible alarm. This buzzer is automatic reset when the refrigerant concentration decreases. The proper functioning can be verified by pushing the test button. Note When monitoring more than 1 detector, the position of jumper BY1, on the detector, should be taken into account. This jumper should be removed for all detectors except the last one. (See also wiring examples on page 6) Fig. 6 Relay function Catalogue Section Johnson Controls Inc.

5 Leak Detecting System 5 Fig. 7 Wiring G27C Fig. 8 Wiring G230C Selection table Item code G27C G230C Enclosure type DIN Rail Mount Wall mount 1997 Johnson Controls Inc. Catalogue Section 9

6 6 Leak detecting system Wiring and mounting information. Detector location Correct placing of the detector is very important. The detector has to be mounted high (under the ceiling, not in the ceiling) for refrigerants lighter than air (Ammonia), and low (20 cm above the floor) for refrigerants heavier than air (CFC, HCFC, HFC). The detector must be mounted at a location where air streams cannot influence the detector.! Warning When wiring or servicing make sure that power supply is switched off. Fig. 9 Catalogue Section Johnson Controls Inc.

7 Leak Detecting System 7 Feature list Detector Monitoring unit GD/GS/GR2.0 G27C G230C Enclosure Wall mount DIN rail mount Power supply 230Vac 12Vdc 12Vac LED indication Power on Device Active Pre-alarm Alarm Fault Alarm memory Output relays Selectable auto reset/ man reset mode Build in Buzzer Alarm test Test Connector Pre-alarm Alarm Fault 24V 24V 24V 24V 24V 230V 230V 230V Optional accessories Item code SA 100 Description Service adapter 1997 Johnson Controls Inc. Catalogue Section 9

8 8 Leak detecting system Check and Calibration of refrigerant detectors To check and calibrate the detector you need a SA 100 service adapter, connected to a multimeter. Working of the detector. The GV value is a voltage proportional to the measured refrigerant concentration. This GVvoltage will increase with an increase in refrigerant concentration. The offset value (no refrigerant measured) need to be checked twice a year. The pre-alarm level and alarm level are set at a particular GV-voltage. A (pre-)alarm signal is activated when the GV-voltage exceeds the (pre-)alarm level.! Note In some cases the detector can give an alarm at start up of the system. This is no fault, it indicates that the detector has to be on for some minutes to stabilise after storing and transportation. The alarm will go off after a couple of minutes. Check and calibrating instructions The first action is to check the power supply to the detector at terminal 1 and 2. This should be 12V ac/dc ±15%. Connect the SA 100 service adapter to the test terminal and do the check /calibration as mentioned in the table bellow. Connect a multimeter to the service module and set the selector to the DC range Fig. 11. Fig. 10 Selector position Correct value Corrective action if value is not correct 5V DC 5V ± 0,15V Replace detector if value is not correct Offset GV-value See table page 9 Adjust the GV offset value using the GV potentiometer. Important: The detector has to be powered for at least 1 hour before checking. Avoid any airflow influence during the test. Zero setting of the GV offset value has to be done in clean air! Alarm level See table page 9 Adjust the Alarm level using the Alarm pot meter. Pre-alarm level See table page 9 Adjust the Pre-alarm level using the pre-alarm pot meter Note: The pre-alarm level is set at a percentage of the Alarm level. When the alarm level is re-adjusted than the Pre-alarm level will follow automatically. Catalogue Section Johnson Controls Inc.

9 Leak Detecting System 9 Trouble shooting Use the SA 100 service adapter, connected to a multimeter Problem Check point Remark Detector gives no alarm at gas influence Constant alarm from detector Constant alarm on monitoring unit Check that the GV-value will increase at gas influence Check the GV-value offset (See calibration instructions) Check that no other gases can cause a false alarm Check for EMC problems. Check if Jumper BY1 is mounted at last detector Check voltage on each detector (between terminal 3 and 4) When voltage is higher than alarm levels the alarm relays should be activated If GV value is higher than alarm level, move the detector to another area with clean air and calibrate If all BY1 jumpers are mounted, a wrong signal is sent to the monitoring unit If detector cable is close to high voltage wiring, electromagnetic induction can affect the detector signal Refrigerant application table and alarm levels Sensor type Refrigerant Pre-Alarm level Alarm level Offset GV Location Gx2.0- CFC CFC s, e.g.: R11, R12, R13, R113, R114, R500, R502, R503 HCFC s, e.g.: R22, R123, R124, R142, R401A/B, R402A/B, R403A/B, R408A, R409A ppm depending on gastype GV = 1,0V ppm depending on gastype GV = 1,0V ppm depending on gastype GV = 1,4V ppm depending on gastype GV = 1,4V 0,35V 0,35V Low Low Gx2.0- HFC HFC s, e.g.: R23, R32, R125, R134, R134a, R143a, R152a, R404A, R407A/B/C, R410A, R ppm depending on gastype GV = 1,0V Gx2.0- NH3 Ammonia, R ppm GV = 2,5V ppm depending on gastype GV = 1,5V 300 ppm GV = 3,5V 0,3V Low 0,2V High Note: The indicated values are typical for ambient temperatures at +20 C. To have an exact value you need to use calibration gas and calibrate at 20 C Johnson Controls Inc. Catalogue Section 9

10 10 Leak detecting system Dimensions (mm) Fig. 12a GD2.0 Detector Fig. 12b GS2.0 Detector Fig. 12c GR2.0 Detector Fig. 12d Mounting dimensions A. Connector CFC/HCFC/HFC: Male 1/2 Flare NH3: Male R1/2 Catalogue Section Johnson Controls Inc.

11 Leak Detecting System 11 Dimensions (mm) Fig. 13 G27C Monitoring Unit Fig. 14 G230C Monitoring Unit 1997 Johnson Controls Inc. Catalogue Section 9

12 12 Leak detecting system Power supply G230 G27C GD/GS/GR2.0 Frequency 50/60 Hz Power consumption GD/GS/GR 2.0 G27C G230 Ambient operating conditions Storage temperature Operating (storage) humidity Detector cable G230C/G27C GR2.0 GD/GS2.0 S pecifications 230Vac/12Vdc +10%/-15% 12Vac/dc ± 15% 12Vac/dc ± 15% 3W 2W 12W 0 to +50 C 0 to +50 C -20 to +50 C -40 to +70 C 10 to 90%RH (non condensing) 4 x 0,75mm 2, Max. 50 m, Screened cable 4 x 1,5mm 2, Max. 150m, Screened cable Terminals Screw type max. wire thickness 2,5 mm 2 Dimensions See drawings on page 10,11 Relay ratings GD/GR/GS G27C G230C Pre-Alarm relay SPST: 24Vac/dc, 1A SPST: 24Vac/dc, 1A Alarm relay SPST: SPST: 24Vac/dc, 1A 24Vac/dc, 1A Fault relay SPST: 24Vac/dc, 1A Directives Low voltage: 73/23/EEC EMC: 89/336/EEC Accuracy ± 15% of adjusted (pre-) alarm level. See page 9 Alarm level See application table at page 9 for factory setting Pre-alarm level See application table at page 9 for factory setting Material G27C G230C GD2.0/GS 2.0 GR2.0 Protection class Weight (g) Max number of connected detectors G27C G230C GD2.0 GS/GR 2.0 G27C G230C GD2.0 GS2.0 GR2.0 SA SPDT: 230Vac, 2 (0,5)A SPDT: 230Vac, 2 (0,5)A SPDT: 230Vac, 2 (0,5)A ABS/PC mixture Polycarbonate Polycarbonate PC, Brass (CFC,HCFC,HFC models)/ Steel (NH3 models). IP 30 IP 65 IP 21 IP The performance specifications are nominal and conform to acceptable industry standards. For applications at conditions beyond these specifications, consult the local Johnson Controls office or representative. Johnson Controls shall not be liable for damages resulting from misapplication or misuse of its products. Johnson Controls International, Inc. Headquarters: Milwaukee, WI, USA European Headquarters: Westendhof 8, Essen, Germany European Factories: Lomagna (Italy), Leeuwarden (The Netherlands) and Essen (Germany) Branch Offices: Principal European Cities. This document is subject to change Printed in Europe Catalogue Section Johnson Controls Inc.