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How to use the Triac to control the 230Vac (L)

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Hi,

Anyone can teach me how to use the Triac to control the 230Vac (L) ?

Thank you..
 

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triacs tutorial

Hi,

Can i use triac to control about 230Vac, 13A (3kWalt) load??

Do you have any recommend component?

Thanks..
 

how to use triacs

No problems with 13A.
I would use something like BTB26 ( **broken link removed** )
or similar.
This on is rated for 25A and 400/600V.
Regards,
IanP
 

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high power triacs

If you want to use it as a switch to turn loads on/off then instead of R1 use a switch, and L1=100µH, and all capacitors should be rated at 230Vac (≈400Vdc).
Regards,
IanP
 

how to use triac

Hi IanP,

Wait har...:) ... i draw and show you the design as you say!!

Thank you.

Added after 52 minutes:

IanP said:
If you want to use it as a switch to turn loads on/off then instead of R1 use a switch, and L1=100µH, and all capacitors should be rated at 230Vac (≈400Vdc).
Regards,
IanP
Click to expand...
Click to expand...

The table show it if we design 240Vac/50Hz the L1 should be 200uH and C1 & C3 = 0.1uF/>240Vdc (~400Vdc) is it??

Actually, what the function for R3 and C3? Is it they made it more stable?
 

triac tutorials

For a "switch circuit" such as you are trying to do you can remove capacitor C2, Diac and R3 - C3 (see snubber circuit). You just don't need them. Leave 3.3kΩ resistor and connect switch directly to the triac's gate.. Done.
Regards,
IanP
 

power triacs

Hi,

If i need to use the logic signal (+Vdc) to drive the Triac's, is it possible, and what should i do??
Is it i need to use one transistor to control the triac's gate??

Thanks..
 

triac power switch

For low power dc control of power triacs you should use an optocoupler such as for example MOC3041 (or similar). This device incorporates a zero-crosing bilateral triac driver.
**broken link removed**
Regards,
IanP
 

electronics tutorial triac example circuits

Hi,

So, at Fig9 pg.4 the MOC3041 pin2 is control by logic signal if the signal is LOW then the two SCR will active to switch ON the 240Vac to LOAD, if the signal is HIGH the two SCR will never swtich ON, am i right??

The story is like that:
Let say ours home application, normaly we use 13A fuse. Let say our's washing machine we use 10A example then it is high Amp.
Can we use the MOC3041 to control, and we must concern the SCR (use the high ~13Amp want) power am i right? And also R1, R2, D1, D2 we must use high walt is it?

Thnaks..
 

tutorial triac

That is righ, signal at the gate output (with pin 1 of MOC connected to Vcc) has to be LOW.
D1 and D2 are standard 1A rectifying diodes (1N4001-4004) and resistors don't need to be bigger than 0.5W.
Good choice of SCRs or triacs will be 2 x max current, so if your device draws 10A use 20A SCRs (triacs) and they are easily controlled by MOC optocouplers (with zero-crossing).
Regards,
IanP
 

use triac as switch

Hi,

Thanks for your solution, but if i decide to use Triac how can i do? Is it follow the Fig8?

The Fig8 circuit is control the high power application is it, what's mean "hot line switching is required"?

Thanks..
 

how to calculate gate resistor to triac

Switching hot lines means that you just switch at the ACTIVE side and load is at NEUTRAL level when the triac is off (in some countries Neutral is at the Earth potential)
But you can use this circuit for both sides switching: Active and Neutral.
Regards,
IanP
 

triac tutorial

Hi,

You mean ACTIVE side is Live 230Vac am i right? and what you mean But you can use this circuit for both sides switching: Active and Neutral ?

The perpose of 39ohm and 0.01uF/400Vdc is reduce the HEAT of triac is it? How they calculate the 360Ohm and 330Ohm and how to decide the value to mask my application?

Thanks
 

snnubers_necesary

ACTIVE is LIVE 230V..

But you can use this circuit for both sides switching: Active and Neutral
Click to expand...
means that the load can be connected as on FIG8 (preferred option), between triac and Neutral, or it can be connected between Active and triac. In this case the bottom part of triac will be connected directly to Neutral.
Regards,
IanP
 

moc3041 snubber

Hi,

Do you know..... the perpose of 39ohm and 0.01uF/400Vdc is reduce the HEAT of triac is it? How to decide the 360Ohm(<0.5Walt) and 330Ohm(<0.5Walt) value to mask my application?

You mean like this..........
 

high power triac

I would use both resistors 330Ω.
On snubber circuits and triacs you can read here:
**broken link removed**
Regards,
IanP
 

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triac katalog

Hi,

Thanks you for your teaching me, i will go through all the information that you given me :) . Then i will try to do practical experiment. If i face any issue we come and discuss again.....

Thank you very much.......
 

triac as aswitch

if i'm using MOC3041 then i don't need any line timing matching circuits, right???
so ow am i suppossed to make control of the output of the triac so it will deliver variable power to the load. I would like to control a heater with moc3041 using variable voltage at the opto coupler MOC3041
 

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