Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Triac/Optoisolator combo - why won't it turn off?

Status
Not open for further replies.
I bought a solid state relay (made of triac with zero crossing detected optocoupler), it turned on/off sine wave AC of Line by 5 volt dc. But it didn't turned off UPS voltage(square wave), it remains always on.
 

But it didn't turned off UPS voltage(square wave), it remains always on.
Yes, this sounds reasonable. A ZC detector SSR doesn't work with square wave. You need at least a sufficient low impedance snubber to reduce dv/dt. But it may not work at all.
 

I tasted it in AC Line of pure sine wave 50Hz, 220V, but when it off, it gave 40V ac on load, why? i tested a triac in same line, but it's ok. (And load current is too small <1A. So di/dt is not problem here)
 

The measurement setup isn't very clear. A residual voltage with high impedance or no load may be caused by the snubber circuit.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top