digital light dimmer

l90mehdi · ‎2016-10-08

Posted on October 08, 2016 at 16:08

hi every one

i am working on the digital light dimmer. i control my ssr by stm32f1.

i have big problem.i want design the circuit that protect ssr(triac) when load will be short so that ssr not damage.

but any method that i know can not hep me.

this topic should be in other group such as power electronic

but if any body know the my question please help me.

Benoit RENARD · ‎2016-12-01

Posted on December 01, 2016 at 11:50

Hello Medhi,

Triac is a device that is automatically turned off at the zero current when not drived by a gate current. No way to turn the device off when the current is flowing.

Even if the Triac technology allows high current robustness compare to MOSFET technology, if a short-circuit of the load appears when the Triac is ON, the way to protect the Triac is to add a fuse in series with the Triac and the load.

To design the fuse and to be sure that the Triac can withstand safely the high current before the cut-off event, take a fuse with a IÂ²t parameter below the Triac specified IÂ²t (see datasheet of your Triac).

Hope it helps,

Best Regards

Benoit

View solution in original post

Benoit RENARD · ‎2016-12-01

Posted on December 01, 2016 at 11:50

Hello Medhi,

Triac is a device that is automatically turned off at the zero current when not drived by a gate current. No way to turn the device off when the current is flowing.

Even if the Triac technology allows high current robustness compare to MOSFET technology, if a short-circuit of the load appears when the Triac is ON, the way to protect the Triac is to add a fuse in series with the Triac and the load.

To design the fuse and to be sure that the Triac can withstand safely the high current before the cut-off event, take a fuse with a IÂ²t parameter below the Triac specified IÂ²t (see datasheet of your Triac).

Hope it helps,

Best Regards

Benoit

Tinh Nguyen · ‎2017-06-15

Posted on June 16, 2017 at 06:57

Hi

Medhi,

Do you know about Triac T1635-700G-TR. I'm doing about this IC.

l90mehdi · ‎2017-06-20

Posted on June 20, 2017 at 15:05

Hi Dear Tinh.

No I am working on power MOSFET

because short circuit protection is impossible with triac.

I'm sorry that I can not help.

thank you