I'm trying to repair a triac motor speed control circuit that is inoperable due to a power spike and is NLA from mfg. It's based on an AC16F triac that tests bad, the gate of which is triggered thru a TO-92 component marked N313. The outside leads of N313 are marked A1 and A2 on the board.
I've not been able to find info for testing or replacement of N313, can anyone help?
Thanks!

 

If you want to test a Triac off board then use a low voltage AC such as a small transformer 6v-12v etc connect the A2 to AC in and A1 to a suitable lamp to the AC return, then momentary connect a 33ohm resistor from G to A2 and the lamp should light if the Triac is good.
Equivalent replacements are available from DigiKey.
Max.

 

Max, thanks for the reply. I may not have been clear, but I know the triac is bad. I need help identifying the N313 component and sourcing a replacement.
Did I supply enough info, or is a schematic needed?

 

The spec sheet is available on line, check the spec's and look for a Littlefuse alternative or equal semi at DigiKey.
The N313 is most likely a Diac they are marked A1 A2 .
http://www.radio-electronics.com/info/data/semicond/diac/diac.php
http://www.digikey.ca/product-detail/en/K1200E70/K1200E70-ND/216075
Max.

 

Could N313 be a low-current triac used to trigger the main triac? More likely though a Diac, as Max says.

 

Thanks for replies. In retrospect I should've mentioned N313 has 3 leads with center lead active in the circuit , so a small signal triac is possible. I cannot find a spec sheet or other info online foe N313. If a schematic is needed I'll have to post one tomorrow when I'm at home.

 

If three lead then it could be a UJT ?
www.mi.mun.ca/users/rmatchim/assign/e1100/triggers.pdf
Max.

 

I'm trying to repair a triac motor speed control circuit that is inoperable due to a power spike and is NLA from mfg. It's based on an AC16F triac that tests bad, the gate of which is triggered thru a TO-92 component marked N313. The outside leads of N313 are marked A1 and A2 on the board.
I've not been able to find info for testing or replacement of N313, can anyone help?
Thanks!

There's an old tradition of using a diac in the gate circuit - but the American semiconductor industry came up with all sorts of variations on the 4-layer device theme.

You could maybe try the DB3 diac:

http://www.farnell.com/datasheets/1689752.pdf

 

can you see which pins the to92 connects to on the main triac, is it G to MT2...

 

Ddave, the gate of the AC16F triac is connected directly with what is labeled A2 (on the pcb) of the unknown component N313 (a TO-92 based component)
So I'm trying to identify N313 for testing/possible replacement. Best guess so far looks to be a small signal triac. I'll upload a circuit drawing tomorrow if I haven't figured it out.
Thanks for all the interest and replies, I appreciate the effort on my behalf!

 

Ddave, the gate of the AC16F triac is connected directly with what is labeled A2 (on the pcb) of the unknown component N313 (a TO-92 based component)
So I'm trying to identify N313 for testing/possible replacement. Best guess so far looks to be a small signal triac. I'll upload a circuit drawing tomorrow if I haven't figured it out.
Thanks for all the interest and replies, I appreciate the effort on my behalf!

The most likely is a small signal triac with no external connection to its gate - its triggered by a specific breakover voltage.

Or in other words - a diac.

 

t I should've mentioned N313 has 3 leads with center lead active in the circuit , so a small .

According to this it sounds to me like all 3 terminals used? UJT etc.
Max.

 

According to this it sounds to me like all 3 terminals used? UJT etc.
Max.

Don't forget there's the UJT and the PUT (programmable unijunction transistor) - which is actually not a unijunction at all, its a thyristor with the gate at the wrong end.

 

Success! Turned out to be a small signal thyristor used to trigger the triac. Replacement arrived and circuit functions.

Thanks for all the replies!

 

Hello Precisionmarine:

I have a PCB:G.S. H.L.LI. PY3H-01

Can you tell me what part number use for replacement a N313 (Small Signal Thrystor)...

And can you help me with the value of resistor R4, R2 and R3...

I receive this PCB with burner a resistors and burn a N313.

I appreciated very much your help. Thank you very much..

 

Hello Precisionmarine:

I have a PCB:G.S. H.L.LI. PY3H-01

Can you tell me what part number use for replacement a N313 (Small Signal Thrystor)...

And can you help me with the value of resistor R4, R2 and R3...

I receive this PCB with burner a resistors and burn a N313.

I appreciated very much your help. Thank you very much..

The only diac I know of still available is the DB3. Breakdown voltage is somewhere around 32 - 34V. They usually come in the same size diode package as the 1N4148, they're frequently blue and have no cathode marker band. They have also started turning up in SMD package. If you can't find a supplier - many CFLs use one in the start up circuit.

Motorola did a large range of 2 pin TO92 trigger devices in various breakdown voltages, both polarised and bidirectional. Whether they still do is another matter.