Product Description

The NB-CH4 module can be used to monitor the methane (CH4) concentration in the air. The module measures the methane in the air with an interval of 15 seconds, displays the current value of the methane concentration on the LCD display and sends information with measured values ​​in the form of radio messages of the mobile operator’s NB-IoT service.

The content of the message is adjustable, in addition to the current value of the methane concentration, the message can also contain values ​​of ambient temperature and humidity, if the used sensor type measures this data. The message can contain only currently measured values ​​or a set of previously measured “historical” readings stored in the module’s memory. The period of storing historical values ​​in memory is adjustable. In one data message up to 48 historical readings can be transmitted. module data measured by internal sensors (processor temperature, internal battery voltage, signal strength data).

The messages are transmitted to the module operator’s application server via the NB-IoT service in the form of standard IP packets routed to the user’s IP network via an access point contractually defined between the GSM network operator and the module operator. The application server of the device operator decodes the messages and further processes the data contained therein.

The methane concentration threshold (alarm limit) can be entered in the module configuration, when the module is exceeded, it switches to the alarm state. The alarm status is signaled by flashing of the red LED under the transparent cover of the module and closing of the integrated electronic switch of the Solid State Relay type – the so-called “alarm relay”, which can start the external signaling control circuit.

When the alarm limit is exceeded, the module can send an alarm message, which also contains the currently measured concentration value at the time of exceeding. This message is sent immediately after the alarm condition is detected and it is possible to set its retransmission with an interval of one minute. This feature increases redundancy when an alarm message is delivered and allows the recipient of the message to monitor the change in methane concentration over a minute interval.

When the concentration drops below the set value, a message is automatically sent stating that the methane concentration has returned to normal. At the same time, the flashing of the warning LED is interrupted and the alarm relay opens.

The module is equipped with a position sensor, which can be used to detect physical manipulation of the module, such as its disassembly or relocation.

The module has a built-in LCD display that shows the current value of the methane concentration found during the last measurement.

The module is enclosed in a plastic box adapted for mounting on a wall or similar structural element.

The module is powered by an internal battery with a capacity of 17 Ah, which allows it to work for up to ten years at a frequency of sending messages 4 times a day (one message can contain up to 48 readings). Battery life can be negatively affected not only by the set shorter measurement and messaging interval, but also by the operation of the device in buildings with a temperature outside the recommended operating temperature range. Frequent switching to the alarm state or long-term remaining in the alarm state, when the power consumption is significantly increased by the closed alarm relay, also has a negative effect on the battery life.

The module is equipped with a SIM card holder for use with a “Micro-SIM” (3FF) format SIM card measuring 15 x 12 x 0.76 mm. The SIM holder is located inside the module on the system board. The module can be made to order with an integrated SIM module (eSIM) of a specific GSM operator.

The module can be checked and adjusted using a configuration cable or wirelessly using an optical converter. The module can also be set remotely, using the return channel of two-way communication.

Key properties:

• Methane (CH4) is the main component of natural gas. The device is primarily intended for monitoring the possibility of natural gas leaks.
• The module is equipped with a very accurate and sensitive sensor that meets the metrological requirements for measuring the methane concentration. The sensor has a guaranteed accuracy and sensitivity of measurement for at least two years.
• The device is powered by a built-in battery, so it can be installed in the gas meter compartment (… where a 220 V supply cannot usually be supplied)
  Installation of the device is very easy.
• The device constantly measures the methane concentration and continuously sends the data to the set computer (application). This will enable long-term monitoring of the development of the concentration value and the adoption of preventive measures.
• The current values ​​can be read directly on the LCD display at any time.
  When the set threshold value is exceeded (when the concentration is already outside the normal range), the LED lights up, the electronic relay closes and an alarm message is sent.
  The LED warns of danger in the immediate vicinity of the module
• A local alarm system, such as a building security control panel, can be connected to the electronic relay. It can trigger an optical or acoustic alarm, send an SMS, etc.
  The alarm message is received by the remote computer and based on it, it can send an SMS or a notification to the mobile phone to the user of the object.
• The module can be used with the NB-IoT communication service, which enables the transmission and storage of messages, viewing of data in the mobile application and sending alarms to mobile phones in the form of e-mails, SMS or notifications.
• The device can also be operated without the NB-IoT service, when data is not transmitted anywhere, but the current values are visible on the display and the alarm is propagated via an electronic relay to the local security system.