Help - looking for 220V power outlet adapter with master/slave function

Thread Starter

Sam the Inrush Current

Joined Feb 1, 2023
Hello Team,
Back 30 years ago I could buy 'power strip' type of adapter that allow it to be plugged in to the GPO (source of 220V) and accept few secondary plugs. It had one master plug with rest operated in slave mode.
Logic was, when master plug draw power, power adaptor switch ON slave outputs. Was used to activate secondary equipment. Say you start saw bench, and it detect current draw and activate outlets that power extraction fan or vacuum.

Does anyone know where you can get them now? I cannot find any!


Joined Jul 18, 2013
Is this for a specific application? , If so there are some devices that will do this from within the device, rather than the power source.


Joined Jan 23, 2018
I am familiar with that functionality. The scheme I saw used two anti-parallel Power diodes to produce a controlled voltage drop of about one volt, which was then used to trigger on a triac to switch on the controlled loads.That was many years ago, the concept is still valid, but I do not recall the exact circuit.


Joined Jan 23, 2018
OK, and it seems that I may have got it wrong. The need is for 220 volts, evidently the in-house distribution. (I am guessing that this would not be in the US, other countries differ.)
The device shown does not make sense as shown, because the text says "Push-button actuation" but the connection picture does not show such. And if it is an amazon item no more information is available. But building "a box" to deliver that exact function at whatever current you need can be quite simple.
Now I have seen that the TS is in an area with 220 volts as the common household distribution voltage Exactly the same scheme that I described in post #4 will work for a 220 volt system. It has been published by others and so various versions are in the public domain. The original that I first saw was in POPULAR ELECTRONICS magazine in the mid 1960s, titled "Uncle Tim."

If we have more information about the application that will help some of us better understand what the solution you seek would be.

I am guessing that this development would be for a standard product, not a one-off home project.
In that case my commercial fees will apply for detailed engineering services.
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