2
\$\begingroup\$

I want to add snubber or supression protection diodes for a solid state relay. Here is the diagram without the diodes:

enter image description here

And this is the SSR I'm going to use: http://uk.rs-online.com/web/p/solid-state-relays/0346895/

What kind of diodes I need and where to place them? The load is a speed controller together with a single phase inductive fan-motor and will not draw more than 1A in steady state.

\$\endgroup\$
3
  • \$\begingroup\$ The datasheet shows a built-in snubber as an option; why do you think you need more? If you get one without a snubber, the equivalent schematic shows clearly where it is placed (values may be interesting to find, though). \$\endgroup\$ May 1, 2016 at 16:04
  • \$\begingroup\$ Sorry I don't understand if I order this relay, how can I know if it has built in snubber? \$\endgroup\$
    – user16307
    May 1, 2016 at 16:08
  • \$\begingroup\$ Btw someone shows connections for the AC output of the same realy totally different here: hobbyprojects.com/quick_circuits_reference/… Isnt that wrong? \$\endgroup\$
    – user16307
    May 1, 2016 at 16:16

1 Answer 1

1
\$\begingroup\$

RS state that that unit has an internal snubber but don't give the full Crydom part number so you can check.

enter image description here

Figure 1. Extract from Crydom Series 1 datasheet.

Contact RS and ask them for the full part number.

\$\endgroup\$
3
  • \$\begingroup\$ Thanks the snubber they show is R C in series not a diode. Why is that? \$\endgroup\$
    – user16307
    May 1, 2016 at 16:46
  • 1
    \$\begingroup\$ Wikipedia has a good paragraph on RC snubbers. It should give you a good appreciation. \$\endgroup\$
    – Transistor
    May 1, 2016 at 16:49
  • \$\begingroup\$ Using diode snubbers with AC power gets... complicated, RC snubbers don't have that problem \$\endgroup\$
    – Sam
    May 2, 2016 at 0:17

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.