Relays are highly susceptible to contamination from flux in the environment. It is recommended to use flux-resistant or plastic-sealed relays to prevent liquid flux or carbon dioxide from infiltrating through the lead-out terminals and the gaps between the base and the housing. For flux-resistant 9V power relays, adopting heat drying (100°C for 1 minute) can further prevent flux infiltration.
When applying flux or performing automatic welding, caution must be exercised to avoid damaging the performance of the relays. Flux-resistant relays or plastic-sealed relays are suitable for dip soldering or wave soldering processes; however, the maximum welding temperature and duration should be controlled according to the specific type of intermediate signal relay selected.
The recommended welding temperature ranges from 240°C to 260°C, with a duration of approximately 5 seconds (250°C is the optimal welding temperature). For other combinations of welding temperature and duration (e.g., higher temperatures for certain welding materials require a corresponding reduction in solder contact time), please contact our technical support team or confirm the welding quality as needed.
The recommended welding temperature is 300°C to 350°C, and the welding duration should be controlled within 2 seconds.
Heat generated in AC power relays during the soldering process can be mitigated by cooling the relays at the end of the production process. Sudden temperature changes should be avoided, and in particular, thermal shock to thermal relays must be prevented.
Welding should use no-clean flux as much as possible. Avoid overall cleaning of the relays to prevent cleaning agents from seeping into the relays and causing malfunctions. Ultrasonic cleaning is strictly prohibited—the mechanical energy of ultrasonic waves may lead to contact spot spattering, enameled wire breakage, and damage to other structures. After cleaning and drying, the relays should be immediately placed in a well-ventilated area to cool down to room temperature.
In some cases, to ensure the water resistance and high insulation of small and medium-sized PCBs (Printed Circuit Boards), it is necessary to apply a protective coating to these PCBs. A relatively flexible adhesive without silicon should be selected. During the automatic dispensing process, negative pressure on the relays must be avoided to prevent the protective coating from being sucked into the relays.
