Can anyone identify this Triac and suggest replacement part?

[aesmith]

Hi,
This is the control board for a poultry incubator, it regulates temperature by pulsing 240V output to the heater. When it's heating up the heater is on full, when it's in control it pulses on and off. The fault is that it can't get up to temperature, it will control stably to a lower temperature but appears not to have enough power.

Testing shows the output to the heater, when on full, shows 130V rather than 240. Without a scope to confirm I'm guessing that it's losing half the AC wave form.

The switching circuit comprises an opto isolator zero volt IC, and a triac. My understanding is that a triac needs +ve at the gate to switch +ve load, and -ve to switch negative. If that's correct then the fault could be either the IC or the output triac.

The triac is marked "912C006", "TIC2" and "PHILIP ES" on three lines. That could be "PHILIPI NES". See photo.

Would anyone be able to identify the part, and suggest a suitable replacement? I can't find any reference to a triac just called "TIC2".

Thanks, Tony S

 

[DPG]

I'd hazard a guess that it's a TIC206 triac, but difficult to be certain. The TIC206 was a very common industry standard device used in loads of equipment. Have built circuits myself using them, although many moons ago.

 

[marconi]

Do you have another equipment of the same type you could check the triac markings? I ask because it is actually PHILIPNES - in the image the N has rubbed off - which makes me wonder if some numbers XY have been rubbed off after TIC2XY. I have found some datasheets of similar triacs but they are labelled TIC2XY. What is the power and voltage of the heater?

PS: A nod to DPG - we are thinking along the same lines.

 

[DPG]

I suspect the fault has caused that part of the triac case to blow out.

 

[aesmith]

Thanks, we do have another incubator of the same make, but it's a later model and in service at the moment. The heater is around 45W, so as far as I can see pretty much any mains rated triac is going to have enough oomph.

I can't see snubbing components, which might narrow the choice down. On the other hand the heater is just conductive traces so may not be that inductive. In fact do you even get back emf with a zero volt switch?

 

[marconi]

Could you give me details of the opto isolator so I can look up what it is able to provide as triac gate drive? Then I can suggest a substitute triac.

 

[DPG]

Could you give me details of the opto isolator so I can look up what it is able to provide as triac gate drive? Then I can suggest a substitute triac.

Maybe the opto triac is one of the MOCP series with zero crossing detection built in.

 

[aesmith]

Could you give me details of the opto isolator so I can look up what it is able to provide as triac gate drive? Then I can suggest a substitute triac.

Certainly, it's an MOC3041, see picture. Any suggestion would be very welcome.

 

[marconi]

I may be wrong but at the moment I think the triac is obsolete - I cannot find it nor any equivalent. I understand from what the OP said that the driver is a separate ic.

 

[DPG]

The MOC3041 has zero detection built in. Used them a few times in the past. Including for a Vic 20 controlled disco light unit!

 

[marconi]

http://www.farnell.com/datasheets/56922.pdf

I think you have a sensitive gate triac - see link above.

This I believe to be a suitable substitute.

ST BTA06-600TW 6A Sens Gate Isol Triac - https://www.rapidonline.com/st-bta06-600tw-6a-sens-gate-isol-triac-47-3390

I would buy this at the same time in case you need to replace the original;

Fairchild Semiconductor MOC3041M Triac Driver Optoisolator - https://www.rapidonline.com/fairchild-semiconductor-moc3041m-triac-driver-optoisolator-58-0892
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The MOC3041 has zero detection built in. Used them a few times in the past. Including for a Vic 20 controlled disco light unit!

It's all coming to light now - tell me(us) more - tell me(us) more:

https://www.google.com/search?gs_ss...9i57j46j0l5.9708j0j8&sourceid=chrome&ie=UTF-8

This was the sort of stuff I danced to (badly) plus the 80s. Happy days.

 

[aesmith]

Thanks all, I had another look and it appears there's dab of lacquer over the lettering, lighting from a different angle shows what I think is TIC206S. And yes I might as well replace the 3041 as well while I'm at it.
Edit - lot's of TIC206 on offer, none with the "S" at the end. Does that matter?


[automerge]1592294777[/automerge]

Edit - lot's of TIC206 on offer, none with the "S" at the end. Does that matter?

Replying to myself, looks like the "S" is the voltage rating. 700V. Based on this data sheet.

TIC206S datasheet

Download TIC206S pdf datasheet file

datasheetspdf.com

I think I should be OK with a 600V rated part (TIC206M). 400V might be a bit tight (TIC206D). Both of those seem readily available.

 

[marconi]

Agreed. Please tell us how you get on.

 

[aesmith]

I've ordered but not received the bits yet. But I had another thought, maybe a bit late. Does the same argument apply to the opto, that 400V might be marginal? Would it be better to use a 3061?

 

[DPG]

I've ordered but not received the bits yet. But I had another thought, maybe a bit late. Does the same argument apply to the opto, that 400V might be marginal? Would it be better to use a 3061?

I'd have said you'd be fine with the 3041.

 

[aesmith]

Agreed. Please tell us how you get on.

Fixed! I needed to replace the opto as well. Without a scope there was really no way for me to test except by replacing the most likely components.

 

[DPG]

Fixed! I needed to replace the opto as well. Without a scope there was really no way for me to test except by replacing the most likely components.

Great stuff! Thanks for letting us know.

 

[marconi]

It is very satisfying fixing something to provide a 'new lease of life'.