We have used BTW69 for power to lead acid batteries for many years. Is device TN 5015H-61 compatible with BTW69? We have maximum current into battery from two alternately conducting BTW's of 30ADC.

[DChil.1]

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[Peter BENSCH]

Welcome, @DChil.1​, to the community!

The BTW69-600RG, for example, is still in full production, so you can still use it.

Probably the feature insulation of the heat sink tab plays a role for you, so that you have chosen the TN5015-6i (not -61). It is a special thyristor with a particularly high operating temperature of 150°C, whereas the BTW69 is only approved for up to 125°C. However, the TN5015-6i differs in some parameters from those of the BTW69-600RG, so suitability depends on your marginal parameters.

The TN8050H-8W is actually more recommended as a more powerful alternative, but it has no insulated heat sink, but a considerably lower thermal resistance, which should reduce self-heating at maximum current.

Does it answer your question?

Regards

/Peter

[DChil.1]

Dear Peter,

That is very useful information. The reason for asking this is that we are getting, suddenly, failures in the field on machines recently sold by our customer. They are panicing a little and have demanded that we come up with an alternative NOT using the BTW as this is suspect. Our supplier has quarantined the stock they have but cannot get replacements quickly. We will try to source the one you mention and I will work out a way of insulating them (probably by insulating the substantial heatsink we use.

Thanks again.

Dave