Author Topic: Can SSR4 switch a low voltage DC load?  (Read 2361 times)

Offline MrC

  • Full Member
  • ***
  • Posts: 59
    • Invitation to Dance
Can SSR4 switch a low voltage DC load?
« on: October 27, 2009, »
Stupid question, and I'm sure I've asked this before.

It looks like the SSR4 can not switch a 5 volt dc load.  Is this correct?  Can the MR16 handle inductive loads (small motors)?

Thanks,

--MrC
Dance like no one is watching!

Offline rrowan

  • Administrator
  • Sr. Member
  • *****
  • Posts: 5899
  • 08096
Re: Can SSR4 switch a low voltage DC load?
« Reply #1 on: October 27, 2009, »
The ssr4 is design for AC usage.

The mr16 will do 0-12 volts DC. For fans you need to use a snubbed circuit to protect the mr16.

Last year I use a mr-16 to control high amp ssrs (puck) with no problems

Rick R.

of course I could be totally wrong.
Light Animation Hobby - Having fun and Learning at the same time. (21st member of DLA)
You are not allowed to view links. Register or Login
Warning SOME assembly required

Offline knguyen916

  • Sr. Member
  • ****
  • Posts: 530
Re: Can SSR4 switch a low voltage DC load?
« Reply #2 on: October 27, 2009, »
You are not allowed to view links. Register or Login
Stupid question, and I'm sure I've asked this before.

It looks like the SSR4 can not switch a 5 volt dc load.  Is this correct?  Can the MR16 handle inductive loads (small motors)?

Thanks,

--MrC

I'm actually messing with small motors with my MR16. The motors require 12v DC which was perfect for the MR16. It's cool to see the dimming effect on the motor. Sorry I kind of sway away from your question. I don't have any 5v dc motors to mess with but im pretty sure you will need to lower the voltage from the MR16 to the motor.
« Last Edit: October 27, 2009, by knguyen916 »

Offline MrC

  • Full Member
  • ***
  • Posts: 59
    • Invitation to Dance
Re: Can SSR4 switch a low voltage DC load?
« Reply #3 on: October 28, 2009, »
Ok.  Can someone with more electical knowledge than me explain why the ssr4 can't pass DC?  By definition, a triac can pass electricity in both directions.  So should the triacs on the ssr4 be able to do so as well?

Thank you,

--MrC
Dance like no one is watching!

Offline RJ

  • Administrator
  • Sr. Member
  • *****
  • Posts: 8519
Re: Can SSR4 switch a low voltage DC load?
« Reply #4 on: October 28, 2009, »
It can! it just will never turn off. There would be no Zero Cross to bring the current to zero and cause the triac to turn of. So it is a one time fire and run forever device.

Seefor some info on the workings of the triac.
You are not allowed to view links. Register or Login

RJ
Innovation beats imitation - and it's more satisfying

Offline MrC

  • Full Member
  • ***
  • Posts: 59
    • Invitation to Dance
Re: Can SSR4 switch a low voltage DC load?
« Reply #5 on: October 28, 2009, »
Thank you!

I now understand!

--MrC
Dance like no one is watching!