Gas Alarm Set GX-A1+CO Sensor

The professional CO detector with external sensor: Detect CO before entering the hazard area, display ppm accurately and shut off the hazard source

The Schabus CO detector GX-A1+CO is a professional CO warning system consisting of a control unit with plain-text display and an external, TÜV-tested CO sensor in accordance with DIN EN 50291 (CO in living spaces). The key advantage: the sensor is installed in the hazard area while the control unit is mounted outside. This allows the hazard situation to be assessed before entering the room. The name says it all: CO detected, danger averted.

The external sensor GX-5042 uses an electrochemical measuring cell and has its own alarm with LEDs, test button and buzzer. The control unit continuously displays the operating status and the CO concentration in ppm. In the event of an alarm, the system warns acoustically and optically both at the control unit and at the sensor itself, and simultaneously switches a potential-free 230 V changeover relay. This allows the hazard source to be shut off: the relay can start forced ventilation, close a solenoid shut-off valve or switch off the heating. A second potential-free changeover relay for faults up to 60 V DC reports technical faults to building management systems, home automation or monitoring systems.

The GX-A1+CO monitors carbon monoxide from incomplete combustion, for example from open fireplaces, Swedish stoves, gas boilers, barbecue systems and pellet bunkers. A cable break detection system immediately identifies damage to the sensor cable. The control unit and sensor are matched to each other and are supplied together.

Safety at a distance

The GX-A1+CO combines a TÜV-tested external CO sensor with a control unit, two relay outputs and a plain-text display.

What is included in the box

The set is ready for immediate use. Control unit and sensor are matched to each other.

• GX-A1+CO warning device with external CO sensor GX-5042 and sensor cable
• Mounting material: 4 large screws, 2 small screws and wall plugs
• Cable glands: 2× M16 and 1× M12
• Detailed operating instructions

The device has no options and no additional variants.

How the GX-A1+CO is constructed

The control unit with display, alarm sounder and relays is housed in a surface-mounted enclosure on the wall. The CO sensor is mounted separately at the desired location and connected via the sensor cable with RJ plug.

Alarm according to DIN EN 50291 and shut-off

The monitoring system is set very sensitively for its purpose and warns at the CO concentrations specified in DIN EN 50291 (CO in living spaces).

When the CO level falls below 50 ppm, the detector resets itself.

Alarm delay times according to DIN EN 50291

DIN EN 50291 specifies alarm delay times depending on the gas concentration. During development of the sensor, the shorter times were given preference.

• From 30 ppm, no alarm may occur within 120 minutes
• From 50 ppm, no alarm may occur within 60 minutes; the device alarms after 90 minutes at the latest
• From 100 ppm, no alarm may occur within 10 minutes; the device alarms after 40 minutes at the latest
• From 300 ppm, the device alarms after 3 minutes at the latest

Relay states

• In monitoring mode the relay is energised (normally open contact closed, normally closed contact open)
• In alarm mode the relay de-energises (normally open contact open, normally closed contact closed)

Correct installation and commissioning

Control unit and sensor are mounted at different locations: the sensor in the hazard area, the control unit outside.

Wall mounting of the control unit

1. Loosen the four housing screws and remove the front panel.
2. If necessary, unplug the ribbon cable at the connector.
3. Mount the base of the housing on the wall using the supplied mounting material.

Position of the external sensor

• The sensor detects only carbon monoxide CO
• CO escaping from gas boilers or similar sources is initially warm and rises
• CO that has equalised to room temperature is slightly heavier than air and sinks towards the floor
• The DIN standard refers to the average nose height of people who regularly occupy the room
• Depending on the source, mounting at breathing height or near the floor is appropriate; if in doubt, ask your chimney sweep

Mains connection and sensor cable

• The cable from the house supply is connected to terminals L, N and PE, which are each duplicated and interconnected
• The sensor cable is 2.5 m long, 3-core and ends in an RJ plug
• The sensor cable can be extended up to 20 metres with 3 × 1.5 mm²
• When connecting at the sensor connection: S = white, M = brown, +24 = green, +5 remains unused

Connecting the potential-free relays

• Re1 (left, “Alarm”) switches up to 230 V, Re2 (right, “Fault”) up to 60 V DC
• Both are potential-free changeover contacts with terminals G (common), Ö (normally closed) and S (normally open)
• The switching current of 5 amperes must never be exceeded
• In the connection example in the operating instructions, Re1 controls a solenoid shut-off valve that is closed in the idle state
• For connection details, refer to the installation instructions of the connected device

Commissioning and function test

1. Apply mains voltage. An electrical function check and a short initialisation phase take place until the sensor has been checked and the sensor self-test has been successfully completed.
2. The display message “CO : Ready” confirms the successful test.
3. The system then monitors the room.

Even after a brief power failure, the function check is restarted. For your safety, the manufacturer recommends regularly checking the system for correct function.

Test the system regularly

The test is carried out using the test button on the sensor. Further tests, for example with test gas, are not required for regular testing.

How to test the GX-A1+CO

1. Briefly press the test button on the sensor: the sensor’s alarm sounder sounds and all LEDs function.
2. Press the test button longer: the ppm display on the GX-A1+CO rises and the control unit also alarms.
3. Check whether connected devices such as solenoid shut-off valve, ventilation or building management system respond as intended.

Behaviour in the event of an alarm

1. Ventilate the room and switch off the CO source to ensure that no further gas can escape.
2. Inform other people to leave the room.

Faults, error codes and care

Detecting and rectifying faults

• The control unit detects its own technical faults and indicates them with an error code or a yellow flashing LED
• Relay Re2 switches and informs, for example, the building management system
• It can take up to one minute for the relay to switch because the device first attempts to rectify the fault by internal restarting
• Disconnect the device from the mains for at least 1 minute and then restart it
• If the fault cannot be rectified, use the SERVICE button to call up the page with the error code and contact support

Error codes

• 1: internal supply voltage too low
• 2: mains supply too low
• 3: sensor or sensor cable defective
• 4 to 9: the yellow, red or green LED cannot be switched on or off
• 10 and 11: internal output fault
• 12: sensor test failed
• 21: memory initialisation failed, yellow LED flashes slowly
• 22: internal software fault, yellow LED flashes slowly
• 23: ambient temperature too low, yellow LED lights continuously
• 24: ambient temperature too high, yellow LED lights continuously
• 25: sensor test failed, yellow LED flashes rapidly
• 26: temperature sensor fault, yellow LED flashes slowly
• 27: memory fault detected, yellow LED flashes slowly

For codes 1 to 12 there is no special LED indication.

Maintenance

The sensor is generally maintenance-free. Only occasionally remove coarse dirt or dust from the device and keep the device and sensor free from moisture. The sensor’s service life depends on temperature and humidity: up to 10 years at a maximum of 28 °C and at least 30 % rH, up to 6 years at a maximum of 40 °C and at least 40 % rH.

Cleaning and care

• Avoid the influence of moisture (splash or rain water), dust and direct sunlight on the device
• Clean only with a dry linen cloth; if heavily soiled it may be slightly dampened
• Do not use solvent-based cleaning agents

Manufacturer’s notes

• Read the operating instructions carefully before installation and commissioning and keep them; they form part of the product
• Installation must be carried out by a qualified specialist; please observe the five safety rules
• Operate the control unit and sensor only together and exclusively in dry indoor rooms with residential-type use, for example living rooms, shops, stores, offices, low-dust workshops and seminar rooms
• The CO gas warning device may only be used together with the supplied CO sensor
• Do not use in potentially explosive atmospheres
• The device is not approved for any use other than that described
• Intended for residential buildings and living areas, sales areas such as shops and hypermarkets, and rooms of small businesses such as workshops and service centres; all installation locations are connected to the public low-voltage network
• The connection cables to the gas detector must be permanently installed as surface-mounted wiring
• The device contains no parts that you need to maintain
• Packaging material is not a toy and does not belong in children’s hands
• The manufacturer accepts no liability for damage or losses of any kind resulting from the failure to give an alarm signal despite elevated gas concentration
• The declaration of conformity is available for download on the manufacturer’s website

Warranty, guarantee and disposal

The GX-A1+CO is covered by the statutory warranty of at least 2 years in the EU. Manufacturer Elektrotechnik Schabus additionally offers a 5-year guarantee that can be registered online. Repair and spare parts are available directly from the manufacturer, even beyond the statutory warranty. The prerequisite is that the device has been used in accordance with the operating instructions. The manufacturer accepts no liability for damage caused by accident, misuse, modification or negligence. If your device is defective, please contact the manufacturer and provide your full address and the reason for return.

The GX-A1+CO does not belong in household waste. The crossed-out wheeled bin symbol on the product reminds you to use the take-back systems for waste electrical and electronic equipment (WEEE Reg. No. DE91394868). This allows the materials to be reused in an environmentally friendly manner at the end of their service life. Information on collection, reuse and recycling systems is available from your local waste advisory service or from the manufacturer.

Why the GX-A1+CO is suitable

Application areas

• Open fireplaces and Swedish stoves: sensor next to the fire, control unit outside
• Pellet bunkers: relay starts forced ventilation in the event of CO
• Boiler rooms
• Gas boiler rooms and gas cookers
• Barbecue systems and open fires, for example in the catering trade
• Technical rooms
• Storage rooms with combustion sources
• Rooms with CO risk that should not be entered
• Shutting off the gas supply or heating in the event of CO
• Connection to building management systems, home automation and monitoring systems

The Schabus CO detector GX-A1+CO: CO detected, danger averted.

Frequently asked questions