The opto coupler fails frequently in the circuit below.

[DIGIPRESSURE]

hello.
I am using bta16-800-bw for 400v 3 phase motor phase control.
In triac control, the optocoupler frequently fails in the circuit below.
For couplers, use moc3071sm, il4208-x007, etc.
Please see photos for symptoms.

I'm thinking of changing to BTA16-800CW.
I'm asking for advice.

and!
bta16-800-bw Snubless type.
Should I install another snubber circuit like the circuit?
Or is it okay not to use a snubber circuit in the triac?
C14, C15, R8, and R9 you pointed out are snubber circuits, and C is the X-cap.

There were cases where this snubber resistor was damaged or burned.
I would like to ask for advice on two phenomena.

The picture on the oscilloscope shows line T + fan W of the circuit tested with a differential probe.

[Peter BENSCH]

To get answers from the English-speaking community, it is helpful to ask in English as well. I have therefore translated your text using a web-based tool:

Hello.
I am using a BTA380-3BW for phase control of a 16V 800 phase motor.
The optocoupler fails frequently in the circuit below.
I use MOC3071SM, IL4208-X007, etc.
See the photo for symptoms.

I am thinking of changing to BTA15-800CW.
Looking for advice.

Second!
Is it ok to not use the snubber circuit in a triac without a snubber? The snubber is built into the circuit separately.

There are times when this snubber resistor breaks or burns out.

The photo of the oscilloscope shows line T + fan W in the circuit tested with a differential probe.

I would like to enquire why you are asking in the community of STMicroelectronics if BTA380-3BW, BTA15-800CW and the optotriacs are not devices from STMicroelectronics?

Nevertheless, I'd like to give you a hint: you probably inserted C14 and C15 to realise a capacitive voltage divider, right? Have you taken into account that the capacitors cause a phase shift?

Regards
/Peter

[AScha.3]

Hi,

1. write in English.

2. try the standard circuit : from ds ->

R = VPAC / ITSM

[DIGIPRESSURE]

hello.
I am using bta16-800-bw for 400v 3 phase motor phase control.
In triac control, the optocoupler frequently fails in the circuit below.
For couplers, use moc3071sm, il4208-x007, etc.
Please see photos for symptoms.

I'm thinking of changing to BTA16-800CW.
I'm asking for advice.

and!
bta16-800-bw Snubless type.
Should I install another snubber circuit like the circuit?
Or is it okay not to use a snubber circuit in the triac?
C14, C15, R8, and R9 you pointed out are snubber circuits, and C is the X-cap.

There were cases where this snubber resistor was damaged or burned.
I would like to ask for advice on two phenomena.

The picture on the oscilloscope shows line T + fan W of the circuit tested with a differential probe.

[DIGIPRESSURE · Accepted solution]

I am using bta16-800-bw for 400v 3 phase motor phase control.
In triac control, the optocoupler frequently fails in the circuit below.
For couplers, use moc3071sm, il4208-x007, etc.
Please see photos for symptoms.

I'm thinking of changing to BTA16-800CW.
I'm asking for advice.

and!
bta16-800-bw Snubless type.
Should I install another snubber circuit like the circuit?
Or is it okay not to use a snubber circuit in the triac?
C14, C15, R8, and R9 you pointed out are snubber circuits, and C is the X-cap.

There were cases where this snubber resistor was damaged or burned.
I would like to ask for advice on two phenomena.

The picture on the oscilloscope shows line T + fan W of the circuit tested with a differential probe.