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Are SSR relays capable of switching on/off 100 times per second for a long time? For example 1 hour?

Does this affect the longevity!?

I want to use relays for 5vdc control and 12vdc output with very low current. But I don't know if it is safe to use it or not.

I have a electromagnetic relay that is capable of doing this, but the datasheet says it shouldn't be used more than 300 times per minute. That's why I want to switch to a better solution.

Update: second in title and body is correct!

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I want to use relays for 5vdc control and 12vdc output with very low current. But I don't know if it is safe to use it or not.

If you are switching DC then you don't need an SSR - use a BJT or a MOSFET. Consider a MOSFET that is used in an off-line switching AC to DC converter - it might be switching 100,000 times per second and for 10+ years - is this enough?

Consider also that is it switching dc currents of a few amps at voltages up to maybe 400 V.

Also what about a class C RF amplifier operating at maybe 300 MHz - its output transistor is switching power at 300,000,000 times per second for possibly several years also.

If you do need galvanic isolation then a photo-voltaic optical coupler can be used to activate/deactivate the MOSFET exactly the same way SSRs use them. Same technology same long-life and gazillions of operations.

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  • \$\begingroup\$ Thanks. I didn't eve think of a MOSFET!!! Lol. The control signal is produced with Arduino. it should be bout 25 mili ampere I think. But i don't know about the current needed to open and close solenoid valves. How high current can a MOSFET work with? Can you specify a model or something? I am not too familiar with them! \$\endgroup\$ – arudino.tyro May 3 '15 at 16:05
  • \$\begingroup\$ Also I'd be thankful if you could give me link that can help me get started with MOSFETs for switching. Especially if it is available for Arduinos. Thanks \$\endgroup\$ – arudino.tyro May 3 '15 at 16:25
  • \$\begingroup\$ I think wiki has a good link en.wikipedia.org/wiki/MOSFET - MOSFETs operate with a voltage placed between gate and source - this voltage (device dependant but in the region of 1V to 20V) can control amps of current and some devices have an "on resistance" that is in the realm of 1 milli ohm. \$\endgroup\$ – Andy aka May 3 '15 at 17:12

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