Due to the rapid development of LED street lamps in recent years, the demand for certification of waterproof connectors is increasing. But many customers are not familiar with the American safety certification standard UL 2238 for waterproof connectors, which is easily confused with the common connector standard UL 1977.

UL 2238 is a safety assessment standard for industrial connectors and waterproof connectors; UL 1977 is a safety assessment standard for data, signal, control and power transmission connectors within or between electronic devices, mainly for commercial or household use. The main differences between the two connector safety assessment standards are as follows:

Scope of products applicable to standards

UL 2238: Connectors for industrial or commercial use, waterproof connectors, etc. Usually not for live plug-in. Connectors can be used outdoors or indoors. The following connector products:

UL 1977: Connectors on commercial or household electronic devices. The live plug-in performance of the connector can be evaluated. Connectors can only be used indoors. The following connector products:

Maximum rated current and voltage of the product

UL 2238: 600 V, 60 A

UL 1977: 600 V, 1000 A; or 6000 V, less than 31 A.

Wiring mode of products

The connection modes of products can be divided into field connection and factory connection.

Field wiring: refers to the connection of connectors in the field of equipment use, according to the requirements of National Electrical Code, NFPA 70 field wiring.

Factory wiring: refers to the connection of the connector in the factory where the terminal product is used.

UL 2238: It is possible to assess the reliability of field or factory wiring of connectors. Products can be UL 62 external line, or UL 758 AWM internal line.

UL 1977: Evaluate only factory wiring products, not field wiring products. Usually, the products are connected with the AWM internal wires of UL 758.

Whether the product can be shipped with wire

UL 2238: Products can be shipped with or without wires.

UL 1977: Products cannot be shipped with wire.

Assessment of Applicable Environmental Grade of Products

UL 2238: Assessment of applicable environmental grade for products, such as type 6P grade for authorized products

UL 1977: No environmental grade assessment is performed for products. ?

Plastic Requirements of Standards for Products

UL 2238: There are requirements for Flame Class, HWI, HAI, CTI, etc. of plastics. The following table shows the minimum requirements for different Flame Classes corresponding to HWI, HAI and CTI:Requirements for RTI (Elec), RTI (Imp), RTI (Str) are as follows:

The RTI value is determined by the minimum thickness of the product or the corresponding RTI value of the larger 3.2 mm.

UL 1977: Only Flame Class and RTI (Elec) for plastics are required. Flame Class requires a combustion grade above HB and RTI (Elec) requires a minimum of 50. Flame Class is determined by the minimum thickness of the product. RTI (Elec) is determined by the minimum thickness of the product or the minimum RTI (Elec) value on the plastic UL yellow card.