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MGS Installation and Operation Manual WARRANTY POLICY MURCO WARRANTS THIS INSTRUMENT, EXCLUDING SENSORS, TO BE FREE FROM DEFECTS IN MATERIALS AND WORKMANSHIP FOR A PERIOD OF TWO YEARS FROM THE DATE OF PURCHASE BY THE ORIGINAL OWNER. THE SENSORS HAVE A WARRANTY PERIOD OF ONE YEAR FROM THE DATE OF PURCHASE. IF THE PRODUCT SHOULD BECOME DEFECTIVE WITHIN THIS WARRANTY PERIOD, WE WILL REPAIR OR REPLACE IT AT OUR DISCRETION.
MGS Installation and Operation Manual ALWAYS INCLUDE YOUR RMA #, ADDRESS, TELEPHONE NUMBER, CONTACT NAME, SHIPPING/BILLING INFORMATION AND A DESCRIPTION OF THE DEFECT AS YOU PERCEIVE IT. YOU WILL BE CONTACTED WITH A COST ESTIMATE FOR EXPECTED REPAIRS PRIOR TO THE PERFORMANCE OF ANY SERVICE WORK. FOR LIABILITY REASONS, MURCO HAS A POLICY OF PERFORMING ALL NEEDED REPAIRS TO RESTORE THE INSTRUMENT TO FULL OPERATING CONDITION.
MGS Installation and Operation Manual Table of Contents Section 1. Overview ....................................................................................... 5 1.1. General Information .................................................................................. 5 1.2. Technical Specifications............................................................................ 6 Section 2. Installation and Wiring ................................................................ 8 2.1. 2.2. 2.3. 2.4. 2.5.
MGS Installation and Operation Manual Section 1. Overview 1.1. General Information The MGS is a state-of-the-art fixed gas detector which can detect a wide range of different gases. The gas sensors can be used on a stand-alone basis or integrated into Controls or Building Management Systems (BMS). The MGS can be used: • in new buildings/areas that require continuous monitoring with high tech gas sensor transmitters. • to add gas detection solutions to an existing system.
MGS Installation and Operation Manual 1.2. Technical Specifications Specification Power Supply Power Monitoring Visual Alarm Audible Alarm Fault Monitoring Analogue Outputs Relay (Digital) Outputs IP Rating Temperature Rating Humidity Rating Dimensions/Weights per Enclosure Type (see Note below) Standard Compliance Description 12-24 VDC, 12-24 VAC 50/60 Hz, 2 W max.
MGS Installation and Operation Manual Supported CFM/Duct Sizes for the Duct Mount Housing Units Duct Size Inches 12 x 12 12 x 24 18 x 18 24 x 24 24 round Feet 1x1 1x2 1.5 x 1.5 2x2 Pi x 1 x 1 1 2 2.25 4 3.
MGS Installation and Operation Manual Section 2. Installation and Wiring WARNING: Explosion hazard! Do not mount the MGS in an area that may contain flammable liquids, vapors, or aerosols. Operation of any electrical equipment in such an environment constitutes a safety hazard. CAUTION: The MGS contains sensitive electronic components that can be easily damaged. Do not touch nor disturb any of these components.
MGS Installation and Operation Manual 2.1. General Placement Guidelines NOTE: The MGS should be installed plumb and level and securely fastened to a rigid mounting surface. Sensors must be located within the appropriate wire lengths from the central control unit (if used). In all cases the sensor supplied is designed for maximum sensitivity to a particular gas.
MGS Installation and Operation Manual Figure 2.
MGS Installation and Operation Manual Figure 3.
MGS Installation and Operation Manual Item Description Enclosure Access To open the standard sensor enclosure (IP41 model), turn the cable clamp 1/2 turn counter-clockwise to loosen the internal gland nut, depress the clip on top of the enclosure and open. Reverse to close. (Note: For the IP66 enclosure, use the four bolts on the front cover.) Power 12-24V AC/DC, connect at positions 0V and +V at connector block CN1. • For AC: Jumper A is on, D is off. (See Figure 2 and Figure 3.
MGS Installation and Operation Manual plant room would be around compressors, pressurised storage vessels, refrigerant cylinders or storage rooms or pipelines. The most common leak sources are valves, gauges, flanges, joints (brazed or mechanical), filling or draining connections, etc. • • • • When mechanical or natural ventilation is present, mount a sensor in the airflow.
MGS Installation and Operation Manual 2.4. Refrigerated Spaces In refrigerated spaces, sensors should be located in the return airflow to the evaporators on a sidewall (below head-high is preferred), or on the ceiling, not directly in front of an evaporator. In large rooms with multiple evaporators, sensors should be mounted on the central line between 2 adjacent evaporators, as turbulence will result in airflows mixing. 2.5.
MGS Installation and Operation Manual 2.6. Air Conditioning (Direct Systems VRF/VRV) For compliance with EN378, at least one detector shall be installed in each occupied space being considered and the location of detectors shall be chosen in relation to the refrigerant and they shall be located where the refrigerant from the leak will collect. In this case refrigerants are heavier than air and detectors should have their sensors mounted low, e.g.
MGS Installation and Operation Manual Section 3. Housing Dimensions Figure 4.
MGS Installation and Operation Manual Figure 5.
MGS Installation and Operation Manual Figure 6. IP66Airflow Duct Mount Housing Units = mm Figure 7.
MGS Installation and Operation Manual 9.8 feet (3 meters) Typical For Dimensions and Mounting Locations , See Figure 5. Figure 8. IP66 Housing with Remote Sensor Head NOTE: For the Exd Remote Sensor Head and 16.4 ft (5 m) cable, the thread varies based on the model.
MGS Installation and Operation Manual Section 4. Operation and Stabilisation On powering up, the MGS will sense for the presence of gas after an initial warm-up delay of 5 minutes. The green LED will flash at 1 second intervals during the warm-up. In an alarm condition: • green LED stays on and the red LED is on • audible alarm operates (if not disabled and after delay, if set). • relay output activates (after a delay, if set) • V and I output changes proportionally with gas concentration.
MGS Installation and Operation Manual Section 5. Configurations 5.1. Overview Function Description Time Delay Available on the audible alarm and relay to avoid false alarms. This is set with jumpers. The default delay is 0 minutes. You may wish to set to 15 minutes during start up. See Figure 2 and Figure 3 for setting the jumpers. Audible Alarm The units have an internal audible alarm. You can disable this by jumper, but the default setting is “enabled” in compliance with EN378.
MGS Installation and Operation Manual Section 6. Functional Tests and Calibration 6.1. Introduction To comply with the requirements of EN378 and the European F-GAS regulation, sensors must be tested annually. However, local regulations may specify the nature and frequency of this test. CAUTION: Check local regulations on calibration or testing requirements. CAUTION: The MGS contains sensitive electronic components that can be easily damaged.
MGS Installation and Operation Manual IMPORTANT: Failure to test or calibrate the unit in accordance with applicable instructions and with industry guidelines may result in serious injury or death. The manufacturer is not liable for any loss, injury, or damage arising from improper testing, incorrect calibration, or inappropriate use of the unit. IMPORTANT: Before testing the sensors on-site, the MGS must have been powered up and allowed to stabilise.
MGS Installation and Operation Manual Bump Test Calibration Exposing the sensor to a gas and observing its response to the gas. The objective is to establish if the sensor is reacting to the gas and all the sensor outputs are working correctly. There are two types of bump test. Quantified: A known concentration of gas is used. Non-Quantified: A gas of unknown concentration is used.
MGS Installation and Operation Manual NOTE: Prior to carrying out a bump test, check and adjust the zero setting as described in the Calibration section. NOTE: Procedures for bump test and calibration vary depending on the sensor technology used and the gas in question. The MGS is available in three sensor versions: Semiconductor (SC), Electrochemical (EC) and Infrared (IR). NOTE: Do not pressurize the sensor. NOTE: For semiconductor sensors, you MUST use calibration gas in a balance of air (not N2).
MGS Installation and Operation Manual Figure 9. Gas Cylinder and Test Hardware Gas ampoules are convenient and inexpensive alternatives to using gas cylinders for bump testing. Step 26 Bump Testing Using Gas Ampoules 1 Make sure that both the ampoules and the calibration beaker are clean and dry. 2 Unscrew the beaker hold screw and place the ampoule so that it sits in the base of the beaker (see Figure 10). 3 Tighten the wing-nut screw onto the ampoule without breaking it.
MGS Installation and Operation Manual Step Bump Testing Using Gas Ampoules 6 Place the beaker over the sensor head using the multi sensor adaptor to fit the sensor, or, if an Exd, IP66 or Remote sensor head version, screw the beaker on the remote sensor head M42 thread or M35 thread adaptor. It should be as tight fitting as possible to allow maximum gas exposure. 7 Tighten the wing-nut screw onto the ampoule until it shatters allowing the gas to diffuse in the beaker.
MGS Installation and Operation Manual • • • Gas cylinder with the appropriate gas and concentration A voltmeter (crocodile clips recommended) Screwdriver (depending on housing). The MGS has three sensor PCB electrochemical (EC), and infrared (IR). versions: semiconductor (SC), 6.4. Calculating Calibration Voltage Sensor outputs are linear. As long as you have a gas cylinder of known concentration you can calibrate to any desired range.
MGS Installation and Operation Manual 6.6. Calibrating Electrochemical (EC) Sensors There are two adjustments required: zero and span. They are monitored at 0V and VS using a 0-5V scale. If the sensor range is 0-1000 ppm, then 5V=1000 ppm. Step Calibrating Electrochemical (EC) Sensors 1 Locate Pot VR201 which is used to adjust the zero point. 2 Monitor the output between 0V (negative) and VS (positive). 3 Adjust Pot VR201 to 0V or slightly positive (0.01 V is acceptable).
MGS Installation and Operation Manual Section 7. Troubleshooting Symptom Green and Red light off Red light on, green led off (indicates a fault) Alarms in the absence of a leak Possible Cause(s) • Check power supply. Check wiring. • MGS was possibly damaged in transit. Check by installing another MGS to confirm the fault. • Sensor may be disconnected from printed circuit board. Check to see sensor is properly inserted into board.
MGS Installation and Operation Manual DECLARATION OF CONFORMITY The manufacturer of the products covered by this declaration: Murco Ltd. 114a George’s Street Lower Dun Laoghaire Ireland Year conformity is declared: 2012 (IEC/EN61010), 2012 (EN 50270) Product(s): MGS Model(s): MGS and MGS Modbus The undersigned hereby declares that the above referenced products are in conformity with the provisions of the following standard(s) and is in accordance with the following directive(s).
