Gas Alarm GX-HS
GX-HS DIN rail gas detector detects LNG, CO, and CO₂ early, activates relays, and provides audible and visual warnings.
€108.40
The Schabus GX-HS: the gas control unit for DIN rail, compatible with various gas sensors, with dual alarm and two potential-free relays
The Schabus GX-HS is a professional gas warning control panel for monitoring a wide range of gases in technical installations. It is mounted on a 35 mm DIN rail (top-hat rail) in distribution boards or control cabinets and serves as an evaluation unit for an external gas sensor. Depending on the connected sensor, it detects and controls LNG, town gas, natural gas and liquefied gases (methane, butane, propane), ethanol, fluorinated refrigerants as well as carbon monoxide (CO) and carbon dioxide (CO₂).
The GX-HS warns already at a gas concentration far below the life-threatening level and is deliberately set to be highly sensitive for this purpose. In the event of an alarm, it signals optically via an LED and acoustically via the built-in piezo buzzer, switches the alarm relay and can, for example, lock a solenoid shut-off valve in the gas supply line. A second relay reports faults, for example to the building management system.
Important note: Installation and connection must be carried out by a qualified specialist; please observe the five safety rules. The GX-HS is a warning device and not a measuring instrument. Without additional redundant sensors, it is not a safety element. It must not be used in potentially explosive atmospheres.
Good to know: The control unit only evaluates what the connected sensor detects. A suitable sensor must therefore be used for each gas type; it is not included in the scope of delivery. Trigger thresholds and minimum concentrations can be found in the operating instructions of the respective sensor.
Detect gas, report and react automatically
For various gases
Depending on the connected sensor, the GX-HS monitors natural gas, liquefied gas, refrigerants, hydrogen, CO or CO₂.
Dual alarm
LED indicator and built-in piezo buzzer report the alarm optically and acoustically at the same time.
Two potential-free changeover relays
One relay for the alarm, one relay for faults, for example cable break at the sensor.
Shut off the gas supply
The alarm relay can switch a solenoid shut-off valve so that no further gas escapes in the event of a leak.
Connection to building management system
The fault relay can operate a switching input of the building management system; connection to a BUS system (EIB) is also possible.
Connect additional devices
The alarm output supplies, for example, an external piezo sounder, an LED or a further relay, e.g. for a warning horn.
Alarm memory
Optionally, the alarm memory retains an alarm even if the gas has already dissipated.
External acknowledgement
A push-button in the control cabinet door or a contact of a GSM dialler resets the detector.
Mains and battery backup
Operation on the mains or on DC voltage, also combined; in the event of a power failure, uninterrupted supply from the battery.
Compact DIN-rail design
DIN-rail housing for distribution boards and control cabinets, all connections as screw terminals.
What is included in the box
The GX-HS has no options and no additional variants. The sensor is not included and is ordered separately.
- Gas control unit GX-HS for DIN rail
- Connection terminals (screw terminals on the device)
- Operating instructions
How the GX-HS is designed
The GX-HS consists of the DIN-rail housing with two terminal rows and a front panel with indicators and buttons. The terminals are numbered consecutively from 1 to 24. All connections are screw terminals: open the screw, insert the wire or stranded conductor, close the screw again. Screw terminals do not serve as strain relief.
Front panel with LEDs and buttons
The red sensor LED indicates the alarm (continuous light) or a fault (flashing). The green power LED lights up during operation and flashes during the warm-up time. With the TEST button you trigger an alarm for testing; with the RESET button you acknowledge the alarm and switch off the alarm tone.
Operating voltage (terminals 1, 2, 3)
Here you connect L, N and PE for mains operation. The device is ready for operation after 8 to 10 minutes.
DC voltage for rechargeable battery or battery (terminals 13, 14)
Alternatively or in addition to the mains, the device can be supplied from a rechargeable battery, a battery or a battery-backed on-board power supply. A 12 V backup supply can be present at the same time as the mains voltage; in the event of a power failure, energy is taken automatically and without interruption from the battery. A simultaneously applied 24 V battery voltage takes priority over the mains voltage.
Fault relay 1 (terminals 4, 5, 6)
Potential-free changeover contact with the connections co, no and nc. In normal operation the relay is energised; in the event of a fault, for example a cable break at the sensor, it drops out. This can be used to operate a switching input of the building management system.
Alarm relay 2 (terminals 7, 8, 9)
Potential-free changeover contact with the connections co, no and nc. It switches when the limit value is exceeded, i.e. in the event of an alarm. Accessories such as a solenoid shut-off valve or a warning horn are connected here. The permissible switching capacity of the relay must not be exceeded.
External acknowledgement (terminals 10, 11)
A potential-free normally open contact with momentary function assumes the function of the RESET button. This allows you to install a push-button in the control cabinet door or to reset the detector by SMS using a contact of the GSM dialler GD-04K (Art. No. 200279). Several push-buttons or contacts can be connected in parallel; the RESET button on the device continues to function.
Alarm output (terminals 11, 12)
A DC voltage is always present at terminal 11; the negative pole at terminal 12 is switched via a transistor (“open collector”) in the event of an alarm. LEDs, piezo buzzers or a further relay can be connected, also in parallel, as long as the permissible load of the output is not exceeded. If terminals 11 and 12 are simply bridged with a wire, the internal piezo is permanently muted.
Alarm memory (terminals 17, 18)
With a wire bridge between terminals 17 and 18 you activate the alarm memory for the alarm relay. It retains an alarm even if the event has subsided again: the relay remains energised, the sensor LED continues to light, the alarm output remains active. Only pressing RESET or closing the acknowledgement contact resets it.
Sensor connection (terminals 21 to 24)
The gas sensor is connected here: terminals 21 and 22 supply the sensor power, terminal 23 is the sensor signal, terminal 24 is ground. Please refer to the operating instructions of the sensor you are using for the exact assignment. Basically only one GX sensor can be operated on one GX-HS.
Free terminals (15, 16 and 19, 20)
These terminals are not assigned.
The matching sensor depending on the gas type
The GX-HS is combined with different external sensors. Trigger thresholds can be found in the respective sensor operating instructions. A list of suitable sensors is available on the manufacturer’s website or from technical support.
GX-LNG, Art. No. 300897
Town gas and natural gas, methane, butane, propane, LNG liquefied gas, camping gas. Use, for example, on gas boilers and gas cookers.
GX-CFC, Art. No. 200901
Chlorofluorocarbons (refrigerants). Use in air-conditioning systems, cold stores and heat pumps.
GX-H2, Art. No. 200616
Hydrogen (H₂). Use, for example, in air-conditioning systems and heat pumps.
GX-CO2-30, Art. No. 300315
Carbon dioxide in technical installations: dispensing systems, breweries, water carbonators, cold rooms, dry-ice storage.
GX-CO2-25, Art. No. 200989
Carbon dioxide in indoor air: indoor rooms, workshops, open-plan offices, waiting rooms, event rooms, classrooms, gymnasiums.
Correct installation and connection
Device and sensor may only be installed in dry indoor rooms and must be correctly positioned depending on the gas type to ensure proper function.
Installation
- Commission a specialist: Installation must be carried out by a qualified specialist. Please observe the five safety rules.
- Place the device on the DIN rail: The GX-HS is installed in distribution boards and control cabinets on a standard 35 mm DIN rail.
- Position the sensor: A prescribed mounting height is required for each sensor type, as gases have different properties and distribute accordingly in the room. Light gases such as methane and hydrogen are detected in the ceiling area, heavy gases such as propane, butane and CO₂ near the floor.
- Read the sensor operating instructions: Mounting height and mounting method must be taken from the sensor’s user manual. For cable extensions, the sensor operating instructions must be strictly observed.
Connection
- Operating voltage: Mains to terminals 1, 2 and 3 or rechargeable battery, battery or on-board power supply to terminals 13 and 14; both together is also possible
- Sensor: To terminals 21 to 24, assignment according to the sensor operating instructions
- Accessories: To the potential-free relays; the permissible switching capacity must not be exceeded
- Alarm memory: Insert a wire bridge between terminals 17 and 18 if the alarm is to be retained
- Internal piezo: If it is to remain silent, bridge terminals 11 and 12 with a wire
- External acknowledgement: Normally open contact with momentary function to terminals 10 and 11
What indicators and relays mean during operation
Monitoring mode
The fault relay is energised, the sensor LED is off, the power LED lights green and the buzzer is silent.
Alarm
The alarm relay switches, the sensor LED lights red and the internal piezo beeps continuously. With alarm memory a manual RESET is required.
Fault or sensor error
The fault relay drops out, the sensor LED flashes red and the piezo alarm beeps.
Warm-up time
The power LED flashes green. If no sensor is yet connected, the power and sensor LEDs flash simultaneously.
Start, test, clean
Commissioning
- Apply voltage: When the mains voltage is applied, the power LED flashes green.
- Wait for the warm-up time: The sensor requires a maximum of 5 minutes to reach operational readiness. Afterwards only the power LED lights green and the GX-HS is ready for operation. After a power failure the warm-up time also starts again.
- Alarm after the warm-up time? After prolonged storage or in the presence of moisture, an alarm may be triggered immediately after the warm-up time (sensor LED lights red). Then briefly disconnect the device from the mains and restart the warm-up time. This may have to be repeated up to three times.
- Perform a functional test: After installation of the GX-HS and sensor, a functional test is required. Testing of the sensor is described in the sensor’s user manual.
Alarm delay
To avoid unnecessary false alarms, an alarm delay of approximately 10 to 30 seconds is set. Only when the sensor detects an elevated gas concentration for longer than 30 seconds does the device trigger the alarm. As soon as the gas has dissipated, the device switches back to monitoring mode. With active alarm memory you clear the alarm with the RESET button; only then does the device enter monitoring mode. As long as an elevated gas concentration is stimulating the sensor, the alarm cannot be cleared with RESET. Without alarm memory only the internal piezo alarm needs to be switched off manually with RESET.
Regular test
- Test every 6 months: For your safety the manufacturer recommends checking the function every 6 months.
- Press the TEST button: This triggers an alarm. It remains as long as you hold the button pressed; with alarm memory until RESET is pressed.
- Check the result: The test only checks the warning device, i.e. LEDs, both relays and the buzzer output. It does not replace the sensor test.
- Replace the sensor: For continuously reliable function the sensor should be replaced after approx. 5 years.
Cleaning and care
- Avoid moisture (splash or rain water), dust and direct sunlight
- Clean the device only with a dry linen cloth; in case of heavy soiling it may be slightly moistened
- Do not use solvent-containing cleaning agents
- Carry out maintenance on the sensor at the intervals specified in the sensor operating instructions
Behaviour in the event of an alarm
How you must react in the event of an alarm or gas odour depends on the type and behaviour of the gas. Please refer to the user manual of the sensor you are using.
False alarms
The sensitive GX sensors also partially respond to other gaseous media. Aerosols (propellant in hair or disinfectant sprays), strong tobacco smoke and cooking vapours can trigger false alarms. Stay calm; there is no reason for an unconsidered reaction.
What the GX-HS is not
- It is a warning device and not a measuring instrument. Without additional redundant sensors it is not a safety element
- It must not be used in potentially explosive atmospheres
- It is intended only for dry indoor rooms; device and sensor do not belong in places with moisture
- It only works with a suitable sensor; without a sensor it detects no gas
- Basically only one GX sensor can be operated on one GX-HS; individual special solutions are possible via technical support
- The self-test via the TEST button does not replace the sensor test
- The device is not approved for any use other than that described
- The manufacturer is not liable for damage resulting from the fact that no alarm signal is given despite an elevated gas concentration
Manufacturer’s notes
- Read the operating instructions thoroughly before installation and first commissioning, especially follow the safety instructions, and keep them for future reference
- Installation must be carried out by a qualified specialist; the five safety rules must be observed
- Be sure to observe the prescribed mounting height and method of the sensor according to its user manual
- For cable extensions on the sensor, the sensor operating instructions must be strictly observed
- The standards according to which the product was assessed provide for use in residential, commercial and industrial areas as well as in small businesses, each connected to the public low-voltage network and in dry indoor rooms
- Packaging material is not a toy and does not belong in children’s hands
- Always carry out the functional test after installation and connection and repeat the test every 6 months
- The declaration of conformity is available for download on the manufacturer’s website
Warranty, guarantee, return and disposal
The GX-HS is subject to the statutory warranty of at least 2 years in the EU for material and quality defects. In addition, the manufacturer Elektrotechnik Schabus offers a 5-year guarantee that can be registered online. Repair and spare parts are available directly from the manufacturer, also beyond the statutory warranty. The prerequisite is that the device has been used in accordance with the user manual. No liability is assumed for damage caused by accident, misuse, modification or negligence.
The GX-HS does not belong in household waste. The crossed-out wheeled bin symbol on the product reminds you to use the take-back systems with which the materials can be reused in an environmentally friendly manner at the end of their service life (WEEE Reg. No. DE91394868). Further information is available from your local waste advice centre or from the manufacturer.
Why the GX-HS is suitable
One control unit, many gases
With the matching sensor for natural gas, liquefied gas, refrigerants, hydrogen, CO or CO₂.
Early warning
Alarm already at gas concentrations far below the life-threatening level, as a preventive safety warning system.
React automatically
Potential-free relays lock the gas supply or inform the building management system.
Dual alarm
LED indicator and piezo buzzer, optionally an external buzzer.
Fits in the control cabinet
Compact DIN-rail housing with screw terminals.
Safe even in the event of a power failure
Battery backup supplies the device without interruption.
From the manufacturer
Made in Germany, German manufacturer since 1992, personal expert advice without call centre, ISO 9001:2015 certified.
Service included
5-year guarantee can be registered, repair and spare parts directly from the manufacturer.
Areas of application
- Heating systems
- Technical rooms
- Commerce and industry
- Control cabinets with connection to the building management system
- Cooling and refrigeration systems
- Breweries and dispensing systems
- Hydrogen applications
- Residential buildings and living spaces such as houses, apartments and rooms
- Sales areas such as shops and hypermarkets
- Rooms of small businesses such as workshops and service centres
- Gas boilers and gas cookers, for example with a solenoid shut-off valve in the gas supply line
- All dry indoor rooms with residential-like use
The Schabus GX-HS: because gas is invisible.
Frequently asked questions
What is the GX-HS suitable for?
The GX-HS is a gas warning control panel for DIN rail. It evaluates an external gas sensor, warns optically and acoustically and switches two potential-free relays, for example for a solenoid shut-off valve or the building management system.
Which gases can the GX-HS monitor?
This depends on the connected sensor: LNG, town gas, natural gas and liquefied gases (methane, butane, propane), ethanol, fluorinated refrigerants, carbon monoxide and carbon dioxide. Hydrogen is detected with the GX-H2 sensor. A suitable sensor must be used for each gas type.
Is the sensor included in the scope of delivery?
No. The sensor is available separately. The scope of delivery includes the control unit, the connection terminals and the operating instructions. A list of suitable sensors can be found on the manufacturer’s website; technical support will also help you with the selection.
How many sensors can I connect?
Basically only one GX sensor can be operated on one GX-HS. For individual special solutions, please contact the manufacturer’s technical support.
Can the GX-HS automatically shut off the gas supply?
Yes. The potential-free alarm relay can switch a solenoid shut-off valve and thereby lock the gas supply line so that no further gas escapes from a leak in the gas line or in the gas boiler. The permissible switching capacity of the relay must not be exceeded.
What is the second relay for?
Relay 1 is the fault relay. It is energised in normal operation and drops out in the event of a fault, for example a cable break at the sensor. This can be used to operate a switching input of the building management system. Relay 2 is the alarm relay.
What happens in the event of a power failure?
A backup power supply from a rechargeable battery or battery can be present at the same time as the mains; energy is then taken automatically and without interruption from the battery in the event of a power failure. Without backup, the sensor warm-up time starts again after a power failure.
What does the alarm memory do?
The alarm memory retains an alarm even if the event has subsided again. The alarm relay remains energised, the sensor LED continues to light and the alarm output remains active until you press RESET or close the acknowledgement contact. It is activated with a wire bridge between terminals 17 and 18.
Can I acknowledge the alarm externally?
Yes. A potential-free normally open contact with momentary function at terminals 10 and 11 has the same effect as the RESET button. This can be a push-button in the control cabinet door or a contact of the GSM dialler GD-04K (Art. No. 200279). The RESET button on the device remains always active.
How do I mute the internal buzzer?
Bridge terminals 11 and 12 with a wire; the internal piezo is then permanently deactivated. Alternatively, connect an external piezo sounder or an LED to these terminals.
Why does the alarm not trigger immediately?
An alarm delay of approximately 10 to 30 seconds is set to avoid unnecessary false alarms. Only when the sensor detects an elevated gas concentration for longer than 30 seconds does the device switch to alarm.
Why are there false alarms?
The sensitive GX sensors also partially react to other gaseous media. Aerosols such as hair or disinfectant sprays, strong tobacco smoke and cooking vapours can trigger false alarms. Ventilate, stay calm and observe the instructions of your sensor.
How often should I test the GX-HS?
The manufacturer recommends testing every 6 months. To do this, press the TEST button; the alarm remains as long as you hold it pressed. The test checks LEDs, both relays and the buzzer output; it does not replace the sensor test. You should replace the sensor itself after approx. 5 years.
May the GX-HS be used in potentially explosive atmospheres?
No. The device must not be used in potentially explosive atmospheres. It is intended for dry indoor rooms.
Is the GX-HS a measuring instrument?
No, it is a warning device. Without additional redundant sensors it is not a safety element. The manufacturer is not liable for damage resulting from the fact that no alarm signal is given despite an elevated gas concentration.
Are there options or additional variants?
No. The GX-HS has no options. It is always supplied with connection terminals and operating instructions. The matching sensor is ordered separately.
How long is the warranty valid?
The statutory warranty of at least 2 years in the EU applies. In addition, the manufacturer Schabus offers a 5-year guarantee that can be registered online.
Questions about the gas control unit GX-HS?
Our support team in Germany will advise you free of charge on selection, installation and configuration.
Gas and Environmental Sensor Control Unit
The control unit is designed for the reliable evaluation of connected gas or environmental sensors. It can be operated with both 12–24 V DC and 100–240 V AC and features potential-free relay outputs for controlling external devices or alarm systems. Thanks to its compact design, the device is ideal for use in technical installations, control cabinets, or monitoring systems.
Technical Data
- Operating voltage: 12–24 V DC or 100–240 V AC (±10 %) / 50–60 Hz
- Power consumption: approx. 1 W (standby)
- Relay contact: 2 changeover switches (potential-free)
- Relay switching capacity: max. 5 A / 230 V
- Sensor connection: 1×5 V DC (max. 200 mA) / 1×24 V DC (max. 150 mA)
- Alarm output: 9–15 V / 30 mA
- Operating temperature range: -10 °C to +60 °C
- Protection rating: IP20 (for dry indoor use), optional IP54
- External dimensions (H x W x D): 57 × 72 × 90 mm (4 height units)
Manufacturer information:
Electrical engineering Schabus GmbH & Co. KG
Baierbacher Straße 150
83071 Stephanskirchen
Germany
Telephone: +49 80 36 / 674 979 – 0
Email: info@elektrotechnik-schabus.de
Responsible person:
Didactum® Security GmbH
Im Mühlenfeld 4
48163 Münster
Deutschland
Fon:
(+49) 250 19 71 63 54 / (+49) 171 33 11 577
Email: info@didactum-security.de
