TKB Home Socket Playing up

[col8eral]

I have a TKB Home Mains Socket which has been working faultlessly for a couple of years, then two days ago it could not be detected by my veralite.  I couldn't even switch it off manually.  I was about to throw it away and thought id plug it in one last time and hey presto its working again.  Any thoughts on why it would behave like that?

[HSD99]

The hardware/software in the plug may have become wedged for any number of reasons, e.g. a powerline hit or other glitch. Powering it off and back on reset the hardware and the software.

[col8eral]

That's interesting as there was thunder and lightning the night before so perhaps that was the reason?

[rigpapa]

Plus one. This time of year we have a lot of lightning in our area. Occasionally a switch will go catatonic, always the low-end ones (Linear/Evolve) that we use in low-traffic areas (closets, storage and utility areas) to try to save a few bucks. Generally, flipping the circuit off and back on at the breaker will reset the switch (sometimes not).

I would watch the device for a while after, though. Internal damage may only be evident with time/under load/etc. I've seen a couple do odd, undesirable things.

[col8eral]

I'll definitely be keeping an eye on it over the next few days all my other devices were fine

Are TKB considered to be a low end device

[HSD99]

Small AC-line powered devices like these have limited protection from powerline transients, especially lightning. It's a matter of cost, but also of size---transient protection devices take up space that may not be present inside a plug-in device. rigpapa makes a good point---keep an eye on your device in case it has been partially damaged by the line hits.

Lightning can affect electronic devices by coupling energy directly onto the power line (direct strike.) Utilities have lightning suppression devices on the power system, but some transient energy can still get through. Indirect coupling occurs via near-field effects---the lighting creates a powerful electromagnetic wave that couples energy by induction into your wiring and electronics.

I design control equipment that is used in theme parks, among other places. Many theme parks are in areas where electrical storms are common. You learn about lightning protection the hard way!

[col8eral]

That was really interesting. I guess these units are a trade off between size and money. Are there strike protectors you can install on the home electrical circuits?

[HSD99]

That was really interesting. I guess these units are a trade off between size and money. Are there strike protectors you can install on the home electrical circuits?

Contact your electric utility. They generally offer lightning/surge protection devices that are installed at your service entrance/main breaker panel. These can be expensive (hundreds of $ with professional installation) but can save you thousands of dollars in damaged equipment. For a plug-in module, plug it into a surge suppression power outlet strip. Beware of inexpensive, "no-name" surge protection power strips---they frequently have poor performance.

And yes, the tradeoff is size, performance and cost. Here's a link to a good technical overview of the problem, and some history: https://www.onsemi.com/pub/Collateral/TND335-D.PDF

[col8eral]

Thank you

[Don Phillips]

That was really interesting. I guess these units are a trade off between size and money. Are there strike protectors you can install on the home electrical circuits?

Contact your electric utility. They generally offer lightning/surge protection devices that are installed at your service entrance/main breaker panel. These can be expensive (hundreds of $ with professional installation) but can save you thousands of dollars in damaged equipment. For a plug-in module, plug it into a surge suppression power outlet strip. Beware of inexpensive, "no-name" surge protection power strips---they frequently have poor performance.

And yes, the tradeoff is size, performance and cost. Here's a link to a good technical overview of the problem, and some history: https://www.onsemi.com/pub/Collateral/TND335-D.PDF

To add to this, I recall decades ago getting involved in surge protection and there are 3 levels - lightning suppression at the service entrance, surge suppression at the panel, and surge suppression at the equipment. Each level is intended to lower the surge to some level so each is needed to protect the equipment. And with each successful absorption of energy, the suppressor is weakened and may need serviced or replaced. Some high-end equipment will give you the joules rating of the suppressor with indicators when the sacrificial parts need replaced.

[rigpapa]

[snip] And with each successful absorption of energy, the suppressor is weakened and may need serviced or replaced. Some high-end equipment will give you the joules rating of the suppressor with indicators when the sacrificial parts need replaced.

To this comment and the earlier comment about "no-name" surge suppressor power strips, I have a standard PSA: Do not use plastic-cased surge suppressors outlet strips. Ever. As Don  points out, the devices used within them to provide protection can be sacrificial. They definitely generate heat when they operate. Your plastic power strip  (name brand or no-name) will valiantly save your computer from the surge, and then ignite it's enclosure and set your house ablaze.

I've made this recommendation for years. A few years ago, a friend of the family ignored this advice and fortunately only lost his kitchen and two adjoining rooms.

[HSD99]

Under a severe fault, the transient protection circuitry can indeed catch fire or even explode. The metal case will absolutely help contain flame or blast fragments. Transient suppressors are designed to protect against short-duration (microseconds) pulses. Each time they act, they degrade a bit and weaken. If you get a long transient (milliseconds) which can happen, for example, during a windstorm when powerlines get shorted to each other, the device will be overwhelmed and may fail before the power company circuit breakers open.

The attached picture shows the inside of a commercial-grade suppressor. Note the size of the suppression and filter components compared to the duplex outlets.

[col8eral]

Thanks.  Will have a search.

My domestic circuit board has contact brakers but non of them tripped during the storm.  I guess they are more for short circuit protection etc.