Heatsink is not required three phase solid state relays

• There is optical isolation between the input and output circuits.
• Tri-color LEDs indicate the switching status.
• The solid-state contactless switch performs zero-crossing turn-on and turn-off, automatically extinguishing the arc.
• When contacts are in a continuous on state, power consumption is low, and there is minimal heat generation; thus, there is no need for cooling measures such as heatsinks or fans during use.
• The product has an ultra-small size, is convenient to install, and can directly replace ordinary relays or contactors.
• The product is mainly used for high-power electrical heating equipment, lighting equipment, reactive power compensation equipment, and electrical switching equipment that require a low switching frequency, prolonged continuous operation time, high working environment temperature, and poor ventilation facilities.

• When selecting a product, it is important to consider the nature of the load and to leave different margins for current and voltage ratings. For a resistive load, the selection can be made at 2.5 to 3 times the load current. For inductive or capacitive loads, the selection should be at 3 to 5 times the load current. Additionally, overcurrent protection measures, such as fast-acting fuses or circuit breakers, should be included in the load circuit to prevent short circuits.
• For inductive (capacitive) loads, overvoltage protection should be applied at the output to prevent thyristor overvoltage breakdown. This can be done by paralleling a Metal Oxide Varistor (MOV) at the output. The MOV should be selected as follows: for a 440V rating, choose between 470V to 680V; for a 660V rating, choose between 1100V to 1200V. Alternatively, an AC overvoltage protection absorber produced by the factory can be used.
• Since this model of solid-state relay uses a composite material structure at the output end, it operates at a lower frequency. If it is to work at high switching frequencies for extended periods, additional heat sinks for cooling may be necessary.
• Because the main switching element of a solid-state relay has a memory function, when the control power supply is connected, the internal control circuit will automatically enter a clearing program, causing the main switch to cycle through an on-off state. This is a normal phenomenon. To prevent instantaneous current impact when starting use, the control power supply should be connected first, followed by the main power supply.