How to test a thyristor?

[Infinity^2]

I am working a a Daytek DT-1704C 17" monitor. It powers up with no
HV. I was prodding around the power supply unit and inside is a
TF341M thyristor (I looked up the datsheet). Using the diode test on
my DMM it measures 0.266V between gate and cathode both ways. Is this
normal? or can a thyristor even be tested with a DMM? If the part is
bad I suspect it is preventing some sections of the monitor from
receiving power. Any advice is appreciated. Thanks.

 

[Sam Goldwasser]

infinity__2@hotmail.com (Infinity^2) writes:

I am working a a Daytek DT-1704C 17" monitor. It powers up with no
HV. I was prodding around the power supply unit and inside is a
TF341M thyristor (I looked up the datsheet). Using the diode test on
my DMM it measures 0.266V between gate and cathode both ways. Is this
normal? or can a thyristor even be tested with a DMM? If the part is
bad I suspect it is preventing some sections of the monitor from
receiving power. Any advice is appreciated. Thanks.

+ o----+-----/\/\---------+-----o Test+
| 100, 2W __|__
| _\/\_ Device Under Test - DUT
12 VDC | R2 / | (SCR or triac).
+---/\/\---o <--' |
1K o |
| |
- o----------------+------+-----o Test-

Apply the 12 V. The device should be off.
Touch the gate R2 - it should turn on and stay on.

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[Ton Visch]

Good SCR tester see:http://www.uoguelph.ca/~antoon/gadgets/scrtest.html
Ton