HBGS – Gas Leakage Sensor for NH3 and CO2

Safety Instructions

⚠️ CAUTION!

Always read the instruction manual before commencing work! Read all warnings to the letter! Installation of the sensor requires technical knowledge of both refrigeration and electronics. Only qualified personnel should work with the product. The technician must be aware of the consequences of an improperly installed sensor and must be committed to adhering to the applicable local legislation.

If changes are made to type-approved equipment, this type approval becomes void. The product's input and output, as well as its accessories, may only be connected as shown in this guide. HB Products assumes no responsibility for damages resulting from not adhering to the above.

ℹ️ NOTE!

The symbol below is used to point out important safety instructions. It will always be found in places in the chapters where the information is relevant. The safety instructions, and the warnings, must always be read and adhered to.

• CAUTION! Refers to a possible limitation of functionality or risk in usage.
• NOTE! Contains important information about the product and provides further tips.

The person responsible for operation must commit to adhering to all the legislative requirements, prevent accidents, and do everything to avoid damage to people and materials.

Intended Use, Terms of Use

The leakage sensor is designed for leakage measurement in and around industrial refrigeration systems. If the sensor is to be used in a different way and if the operation of the product in this function is determined to be problematic, prior approval must be obtained from HB Products.

Prevention of Collateral Damage

Make sure that qualified personnel assess any faults and take necessary precautions before attempting to make replacements or repairs, so as to avoid collateral damage.

Disposal Instructions

The sensor is constructed so that the modules can easily be removed and sorted for disposal.

Introduction

The HBGS sensor fulfills the requirements for gas leakage measurement in accordance with F-GAS regulation EU/517/2014. The HBGS detects NH3 (R717) in different ranges from 0-100 ppm up to 0-15 % and CO2 (R744) in a range of 0-10000 and 0-20000 ppm. It is an independent unit that must be supplied with 24 V DC. It has 3 built-in digital alarm outputs and one analog 4-20 mA output. The alarm settings can be adjusted using a PC with the HB Configuration Tool and a special USB cable and adapter.

Design and Function

NH3 sensor versions up to 5000 ppm use a sensor head with a lifetime of two years in severe conditions, and longer if no NH3 is present during normal operation. CO2 sensor versions and the NH3 15% version have a lifetime of more than 5 years. All sensor elements can easily be replaced and do not require new calibration.

On the front, there are 4 integrated LEDs: a green LED for power supply indication, and red, orange, and yellow LEDs for the 3 alarm levels.

A reset button (labeled 'R') is used for resetting after an alarm and for putting the sensor into service mode, which is used during maintenance with a controlled gas leakage. The sensor is factory calibrated and only requires additional calibration in special applications.

The sensor is optimized for use in machine rooms and similar environments. A built-in heating element ensures operation in ambient temperatures down to -30 °C.

The sensor is supplied with a calibration certificate and pre-configured alarm limits.

Technical Data

Supply voltage:

24 V DC – Power consumption max 3 watt

Connection:

Screw terminals

Cable glands:

2 x PG7

Alarm Configuration

Can be configured with HB-tool and an USB cable and an adapter.

• Measurement accuracy NH3: Repeatability +/-10%
• Measurement accuracy CO2: Repeatability +/-2%

Standard Alarm Configuration

Factory settings - alarms according to EN378 and other relevant standards:

Output

• Analog output: 4-20 mA
• Max load: 500 ohm
• Alarm output: 3 x SPDT, 0.5A

Installation Conditions

• Ambient temperature: -30...+50°C
• Waterproof rating: IP20, box IP65

Certifications

• EMC Emission: EN61000-6-4
• EMC Immunity: EN61000-6-2

Mechanical Specifications

• Dimension: 82 x 59 x 126 mm
• Material: Plastic
• Mounting: On walls with screws

Application Examples

The sensor is designed for leakage measurement of refrigerant in industrial refrigeration systems. It can be installed where gas can potentially leak, typically in the machine room or where evaporators or condensers are located.

Installation Instructions

General Installation Instructions

The following applies to system design:

1. The sensor may be installed and supplied with a standard unshielded cable. If the EMC requirements are higher than described in EN 61326, a shielded cable must be used.
2. If the sensor is mounted in dusty conditions or where water is used for cleaning, the sensor head should be pointing downwards to prevent blockage or damage from water. A protection for the head is recommended during cleaning with water. Remember to remove the protection after cleaning.
3. It is recommended to install the sensor in stairways and other places where gas pockets can form.
4. If a ventilation system is installed, it makes sense to place a sensor at the inlet.

Special Instructions for NH3

Ammonia is lighter than air, so the sensor should be installed above potentially leaking components or at least 1.5 m from the ground.

1. The sensor must be mounted at a distance of at least 150 cm from the floor.
2. Near safety valves, the sensor must be placed 1-2 m above the outlet to ensure a fast reaction.

Special Instructions for CO2

CO2 is heavier than air, so the sensor should be installed below potentially leaking components and maximum 0.5 m from the ground.

1. The sensor must be mounted maximum 50 cm above the lowest point in the room.
2. If there is a basement in open connection with the machine room, the sensor should be placed there.
3. Near safety valves, the sensor must be placed below the outlet to ensure a fast reaction.

Recommended Installation Locations for Refrigeration Systems

HB Products recommends sensor installation at the following locations:

• A. At the safety valve and valve stations
• B. In the machine room
• C. At the pump separator
• D. At the evaporators
• E. At condensers when mounted indoor

Electrical Connection

The sensor is supplied with 24 VDC.

The sensor can be connected directly to a siren using the Alarm A, Alarm B, Alarm C outputs and ground. Simultaneously, the 4-20 mA signal can be sent to a PLC.

The analog output signal is linear with the gas content.

The cables used for connecting to the PLC and for the siren must be mounted with the ferrite clamps included in the package. They make the sensor less sensitive to EMC.

A Nexus 105 Siren with orange flash has a power consumption of max 1.6 watt and can be controlled directly.

Functionality

LED Indication

On the front of the sensor, LED indication is integrated for power supply ON and alarm indications A, B, & C.

• Alarm LED (3 alarm levels) is activated in case of a leak.
• Power LED is activated when the sensor is being connected to power.

Alarm Reset

In case of a leak, an alarm is triggered. The alarm can be reset by holding down the 'R' button for a few seconds. If the alarm activates again after reset, there is still a gas leak in the room.

Service Mode

The sensor can be put into service mode, which means it will not react to gas for 60 minutes or until switched off again. Service mode is activated by pressing the 'R' button for a minimum of 15 seconds until the 'Power ON' LED starts to flash fast. Returning to normal mode is done by pressing the 'R' button for a minimum of 15 seconds until the 'Power ON' LED shows a constant light for more than 5 seconds.

Lifetime and Verification

The NH3 sensor head measuring up to 500 ppm has an expected lifetime of two years. The sensor output can drift up to 2% per month and is affected by the gas level content in the area – these factors set the lifetime to two years.

The CO2 sensor heads and the 15% NH3 sensor heads have a lifetime of at least 5 years.

Sensor verification must follow local requirements and can be performed using a suitable test gas and a test kit. Test gases must be purchased locally as they are subject to shipment restrictions.

Accessory for Test and HB Tool

The service kit can be used for both NH3 and CO2.

• Part no. Service kit: HBGS-ServiceKit
• HBGS-ServiceKit includes:
  • Cup and tube
  • HBxC-USB (Cable)
  • HBGS Adaptor

This kit is used for gas testing and as a connection cable for the HB tool, which is used for modifying alarm limits.

Configuring the Sensor

The HB Products PC-Tool can be found at: https://www.hbproducts.dk/en/hb-tool

Unscrew the two Philips screws on the top and connect the HBxC-USB to the HBGS-USB-ADAPTOR. Connect the HBGS-USB-ADAPTOR to the M12 circular connector of the main unit. Supply the sensor with 24VDC.

The alarm settings can be typed in and saved to the sensor. All alarms can be configured as either NO (normally open) or NC (normally closed) with reference to the contactor. NO means the contactor will be closed when an alarm occurs, and the siren will start if connected. NC can be used to make the installation safer and detect a broken wire, but it requires a siren with a similar function, which means it makes an alarm when the signal is removed.

[Screenshot of the HBGS-NH3 Tool software interface. It shows sections for Basic settings, Communication settings, and HBGS-NH3 basic settings. Users can input alarm set points in ppm for Alarms A, B, and C, and select the output type (NO/NC). There is also an option to select the Sensor type (e.g., NH3) and a Configuration Instruction panel guiding users through setting up the sensor, reading current configuration, changing parameters, and saving to the sensor or resetting to default.]

Sensor Repair

A new sensor head can be ordered with product no. HBGS-NH3-UNIT or HBGS-CO2-UNIT. The sensor head can be replaced directly and requires no calibration.

If you have questions about the product, please contact HB Products' dealers/distributors. Please consider their complaint procedures before returning the sensor.

Further Information

For further information, please visit our website: www.hbproducts.dk, or send an email to: support@hbproducts.dk.

HB Products A/S – Bøgekildevej 21 – DK8361 Hasselager – support@hbproducts.dk – www.hbproducts.dk

Using the Sounder Beacon (Klaxon Nexus 105)

This section describes the connection diagram with a Sounder Beacon.

This connection will:

• Turn on the siren when the alarm level C is reached.
• Turn on the flash when the alarm level B is reached.
• Provide an alarm to the alarm system when the alarm level C is reached.

[Diagram illustrating the electrical connection between the HBGS Gas Leak Detector and a Klaxon Nexus 105 Sounder Beacon. The diagram shows the power supply connections for both devices, and the alarm outputs (Alarm A, Alarm B, Alarm C, 4-20 mA) from the HBGS sensor connecting to the siren's sound unit and flash unit. It also indicates a connection to a PLC Alarm system unit.]

Using Different Siren Levels

The Sounder Beacon can provide different sound levels. The connection requires the use of relays and a different wiring.