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Son off Pow R2 for 220V AC Unit only has 1 input for wiring

I bought a SonOff pow R2 to work with my 220V A/C Unit . My electrician says it cant work because our 220 V system uses 2 input wires but the sonoff only uses 1. he said something about it being a europpean system being different. What can he do to work around it?

It should work  ...but...  Keep in mind that the start current (inrush) on that AC unit will be  3 to 8 times the running current so if it pulls 8 amps when running it might pull over 60 for a split second when it starts.  Also keep in mind that the ringback voltage when the circuit is opened may be several times the line voltage and cause a great arc flash.  HVAC contactors are designed to handle this.  That tiny relay inside the Sonoff is not.  So don't be surprised if your Sonoff relay contacts get vaporized after a few cycles.  This is a highly inductive load you are switching.


My 2 cents worth, and I have said it before, If you are going to switch a 240V single phase motor load then do it right to start with.  Use the Sonoff to operate the coil of a proper contactor.  If you don't, you are going to be disappointed and potentially unsafe. 

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