Does a triac switch DC ?

[Linden]

Im trying to make a solid state relay with a triac (BTA16 600B)

Im just testing it by turning on the gate and trying to pass a DC
current through the terminals 1 and 2.. doesnt seem to work, yet it
works when trying to pass a current through terminal 1 and the gate ?

Unless the data sheet is wrong in its pin layout !

 

[CFoley1064]

Subject: Does a triac switch DC ?

From: Linden [email protected]
Date: 10/14/2004 7:57 AM Central Daylight Time
Message-id: <[email protected]>

Im trying to make a solid state relay with a triac (BTA16 600B)

Im just testing it by turning on the gate and trying to pass a DC
current through the terminals 1 and 2.. doesnt seem to work, yet it
works when trying to pass a current through terminal 1 and the gate ?

Unless the data sheet is wrong in its pin layout !

A TRIAC will switch DC on, but then you've got a problem -- it won't turn off.
TRIACs are made to switch alternating current. The device will turn off when
the voltage and current across the device is sufficiently low.

If you try something like this, the TRIAC will never turn off (view in fixed
font or M$ Notepad):



.------o---------.
| | |
| | |
| | |
| .-. |
| | | .-.
| | | ( X )
--- '-' '-'
- | |
| | T _|_
| | --- V_A
| '---o o-/ |
| |
| |
'----------------'
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de


If you want to make a SSR to switch DC, use an optoisolator and a transistor or
power FET. And the data sheet is right about 99.999% of the time, if it's not
a preliminary data sheet. Always look at your wiring and circuit first.

Good luck
Chris