Waterproof junction boxes are often used in construction sites, mines, cabins, outdoor electrical, communications, fire-fighting equipment, steel smelting, petrochemicals, electronics, electricity, railways, construction sites, mines, mining sites, airports, hotels, ships, large factories, coastal areas Equipment such as factories and unloading docks is one of the electrical wiring materials for electricians. Equipment installation sites are often wet and prone to flooding. Problems such as instrument and telemetry terminal unit (RTU) failure are often caused by poor waterproofing of junction boxes, which solves the problem for construction units. trouble. So, what are the UL flame retardant grades of junction boxes?

1. UL94HB: Horizontal combustion

This plastic burns slowly but is not self-extinguishing. It is the lowest level of UL and is often used when the vertical V0, V1 or V2 method is not feasible. If the aging and UL testing have not been completed, the plastic products will be put into the market, or if other methods of evaluation are not feasible, this method will be used. This is a temporary and regular final evaluation method for plastics.

2. UL94V0, V1, V2, V5: vertical combustion

UL flame retardant classification is as follows:

UL94V0 and UL94V5 are plastic “insurance” classification methods. After the flame is removed after ignition, the sample can quickly self-extinguish to no burning melt dripping within a certain time gap (that is, the burning melt Drops placed on a cotton pad located one foot below the test specimen shall not ignite the cotton). The flame length is required to be 3/4 inches, and two combustions are required for each flammability test using UL94V0, V1, and V2.

UL94V2 is the same as V1, except it allows burning droplets to ignite cotton up to a foot below.

UL94 V5 is the most stringent testing method. It designs the actual lifespan of plastic products in the flame. The experiment requires a flame length of 5 inches, and the test sample is burned 5 times. During this period, no melt droplets are allowed to drip, and the test sample is not allowed. There is obvious distortion, and no burnt holes can be produced.