* Notice and Cautions before using SSR:

1- SSR is current drove, when used in logic electrocircuit, try to drive by low voltage +5V DC, to make sure enough load capacity and zero voltage.

2- Multiple SSR input terminals can be connected in Series or in parallel,to make sure each SSR high voltage contact current≥6mA、contact voltage≥4V,viz. in parallel connection, driving current≥the sum of each input current; In series connection, driving voltage≥the sum of each turn-on voltage (suppose driving voltage=4V).

3- RC absorb loop and off leak current: the Purpose of RC absorb loop is to absorb the surge voltage and increase dv/dt index,

but SSR internal RC loop can cause about 1~2mA off leak current. According to experiences, SSR＜10A doesn't influence load up to 50W (e.g.motor). Besides, in application of huge inductance load, SSR can be protected by connecting RC absorb loop in parallel with SSR output terminals.

In case SSR is used in power extend application, RC absorb loop may cause misaction when power on, therefore, when ordering, customers should indicate the application of SSR, RC absorb loop can be eliminated.

4- Over current ,over voltage protection methods:over load and load short circuit is the main reason of damage to SSR. To protect from damage, limit fuse or air switch can be configured with, and magnetism fuse adopted for low capacity SSR.

Over voltage protection: in addition to RC absorb loop, metal oxidation resistance（MOV）can be connected in parallel. The size of MOV is decided byabsorb power, and the thickness of MOV decide the protected voltage value. In normal condition, SSR of 220V can use piezoresistor at 430~600V, SSR of 220V can use resistance at 750~850V.

At 50A equals to heat produced by iron of 60W. When design for dispersing heat, ambient temperature、circulation conditions (such as natural cooling, fan cooling) and SSR installation density should be taken into account. SSR of 2A~5A needn't radiator; SSR ＜ 10A to work long time only need toinstall flat metal piece with good dispersing heat; SSR ＞ 10A need to configure related radiator, but should be cooled by fan when ＞60 ℃.

6- SSR selection for load surge current: Most load may cause surge current at the instant of turning on, surge current is

another key reason of damage to SSR when heat is not dispersed in time. Therefore, to select SSR, current range is better to reserve some space.

Load like incandescent lamp and electric cooker thread can cause 10 times surge current for lasting 1 cycle, this is smilar to SSR anti-surge current feature. To selecting strong SSR, current should be equal to 1.8 times of rated current of electric cooker thread and 1.5 times of rated current of incandescent lamp.

AC electric magnet and general relay may cause 4~5 times surge current; AC motor may cause 5~7 surge current when turning on for lasting 10cycles. For normal SSR to control motor, SSR current range should be 7 times of motor rated current.

7- Cautions for testing SSR: in normal condition, AC SSR has a internal absorb loop and there is a leak current about 0.5~2mA,

therefore, when SSR input terminals without control voltage , to measure output terminals by voltage meter, meter still displays voltage. Correct testing method is to connect a lamp up to 15W, connect voltage meter to lamp.