UL60335-2-40 is an electrical safety standard for air conditioning and refrigeration equipment in North America, and Edition 3 adds a safety feature for A2L refrigerant.
In Edition 3, a safety function for A2L refrigerant will be added to the standard. Since A2L refrigerant is a mildly flammable refrigerant that is increasingly being introduced in response to greenhouse gas emission regulations, the incorporation of a refrigerant leak detection mechanism will be mandatory in Ed.3.
The security functions to be added in Ed.3 include alarm triggered by leak detection, shutoff by shutoff valve, and gas diffusion by fan operation.
UL60335-2-40 Ed.3 will be applied to North America. The application of UL60335-2-40 Ed.3 is scheduled for 2023 in North America and will be extended to other regions and products as corresponding laws and regulations are developed.
A2L refrigerants include R32, R1234yf, and its blends such as R454 etc.
The UL standard specifies that a leak of a mildlly flammable refrigerant must be detected within 10 seconds.
Mildly flammable refrigerants have an increased potential to burn as their concentration increases.
Therefore Refrigerant Sensor need to detect the leak as soon as possible.
Nissha FIS has achieved a response time of less than 10 seconds as required by the standard.
UL standards require a concentration detection accuracy of within ±15%.
The test results on the right show that Nissha's semiconductor sensors can meet this requirement.
The test results on the right show the possibility that Nissha FIS semiconductor sensors can meet this required accuracy.
＊No UART Signal Output
②Detector at Low position in the room
③Exterior unit in a location isolated by a wall
＊Since the specific gravity of refrigerant is heavier than that of air,
it is necessary to install it at a lower position than where there is a possibility of leakage.
The sensor module is available individually or with a case for protection and mounting.
It does not require calibration after installation and can be used for 10 years without replacing the sensor.
The system is equipped with filters for spray gases used in daily life to reduce the risk of false alarms.