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.

Register Log in

[SOLVED] Photo Coupler (Opto coupler)

Status
Not open for further replies.
S

srinu9009

Junior Member level 1
Joined
Sep 4, 2008
Messages
18
Helped
4
Reputation
8
Reaction score
1
Trophy points
1,283
Activity points
1,393
Hi All

I am using Two optocouplers to my inverter mains mode to invereter mode application.I used one opto coupler for zerocrossing detector and another for mains sensing voltage.i connected these optocouplers inputs in series.is it working at all conditions?i am sending schematic as file.

if optocouplers inputs connected in parallel or in series then will it create any problems?

Like mosfets can i connect optocouplers in parallel or in series
 

you dont need all those diodes to get mains crossing

you just use the one opto diode with protection diode across it and dropper res
 

Hi eem2am

Thanks for your reply.i do not undersatnd where can i place protection diode? can i use in input side of optocoupler ?
 

you dont need all those diodes to get mains crossing
Click to expand...
A bridge rectifier gives 100 Hz output, your suggested protection diode circuit 50 Hz. Both serve different purposes. A symmetric 100 Hz phase angle control should use the bridge rectifier circuit, a full wave control the single diode variant.
 

The zero crossing voltage and Mains sensing voltage outputs are also just negated versions of each other, so you could remove one of the optocouplers and replace R6 and 7 with a single 47k 2W (it would run hot at 300v) or higher wattage rating.
In your current schematic if any one of the components fail, the lot stops, so simpler with less components is less points of failure.
 

Hi,

Use just one optocoupler and you will know neg-pos zero crossing. The you can calculate for pos-neg zero crossing. However keep two resistors for better performance and power dissipation (even using 4-6 resistors would be easier for power handling).

Kind regards
Hakeen
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top