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SSR use requirement, please pay attention to the following:

1. The SSR for current driven, should as far as possible when logic circuit drive with low level 8 VDC, 12 VDC output drive, in order to make sure there is enough on load capacity and zero level as low as possible.

2. Multiple SSR can input string, in parallel, but should meet the drive current should be greater than the sum of multiple of the input current in parallel, series connection should be greater than the sum of multiple open voltage when the driving voltage.

3. RC absorption circuit and off state leakage current, the effect of RC absorption circuit for enhancing absorption of surge voltage dv/dt index, but the SSR RC circuits inside off state leakage current according to the experience, the following 10 a SSR the leakage current of more than 5 w power of the basic no impact load (motor), a more than 40 SSR leakage current basic no effect for more than 25 w power load. In the practical application of large inductive load, also can be in SSR two outputs and parallel RC absorption circuit in order to protect the SSR

4. Flow over voltage protection, over current and load short circuit is the main cause of SSR permanent damage, selects the fast fuse and air switch is one of the over-current protection method for small capacity of SSR also can choose magnetic substance fuse. Overvoltage protection in addition to the SSR have internal RC absorption circuit, can also be used in parallel metal oxide arrestor (MOV), MOV area size decided to absorb the power, the thickness of the MOV decided to protect the voltage value. 220 v series SSR can generally arrestor, 430 v to 430 v, 380 v series of SSR can be 750 v to 750 v arrestor.

5. Load surge of SSR features selection: many load in the switching moment can produce large surge current, due to the heat dissipation is not timely, surge as well as the flow is the main cause of damage of SSR in incandescent electric stove wire such as load through nearly 10 times of the surge current, the last one cycle or so, with this type surge flow resistance characteristics of SSR phase close to select the current level of enhanced SSR should choose 1.6 times the rated current of the electric stove wire and 1.5 times the rated current of the incandescent light bulb.

6. The heat and cooling: SSR in the biggest heat conduction according to the actual working current * 1.2 W/A to calculate, when thermal design, should take into account the environmental temperature, ventilation (natural cooling fan cooling) and SSR installation density factors such as 2 A 3 A 5 A series without additional radiator spiral SSR when applied in the following 10 A current for A long time just installed on the heat dissipation good metal plate or solid brand on the special guide bracket, more than 10 A need to put on the radiator, when the current is greater than 40 A need to use fan cooling.

7. Install Caution:

  a) According to the selected current relay, matching the radiator dimension and environmental conditions can use natural air forced air cooling or water cooling, due to the solid state relay is a type of insulation, therefore, can make more solid state relay installed to the same radiator.

  b) The radiator installation surface should be smooth, no scratch and sundry, the surface finish should be less than 10 um.

  c) To install solid state relay on the radiator before applying a sandpaper gently wipe the radiator surface oxide layer and anhydrous ethanol wipe, and then they contact surface between evenly apply a thin layer of thermal conductive silicone (each about 0.5 um thick), make it good to reduce the contact thermal resistance for solid state relay heat dissipation, can make it work in the best state.

  d) Module is used when fastening to the radiator surface M3 and the M5 screw and spring washer, and with 0.58 0.98 N.M, 4-6 n. M torque tighten.