Electrical Wiring in the Home/In wall Timer switch


QUESTION: I want to replace a single pole switch that powers my porch light with a switch/timer. I purchased a Woods Timer Switch Model #59020. It says "no neutral required". The timer has a black, red, and green wire. It says the switch will not work unless the ground wire is connected to the ground wire in the  electrical box.I don't see a green ground wire in my electrical box. My existing single pole switch is connected as follows:
From the existing switch terminals:
A white wire from the top of the switch runs to a wire nut which has  black and white wires coming from the wall
Bottom of the switch has a black wire connected to it which comes out of the wall

Tied together with a wire nut are four wires:
White wire from the switch
Another white wire from the wall
2 black wires from the wall

Can you advise how to wire in the timer, and do I have a ground wire?

Not sure if this matters, but there is a three way switch right  next to the porch light switch , (for the foyer).



Assuming you have no bare ground wire  either you must connect the green wire from the timer to the metal of the box. You will need a 10/32 green ground screw to do it. There are spare tapped holes in the back of the box you can thread the screw into.


---------- FOLLOW-UP ----------

QUESTION: thanks! Could you also advise, based on my description of the wiring in the box, how I should connect the timer's black and red wires? Many thanks....


Determine which of the 2 wires on the existing switch is the "Hot". You will need some sort of tester to do this. A Voltage sensor stick would work or a volt Ohm meter or a "solenoid" type voltage tester. Connect the "Hot" wire on the switch to the black wire on the timer. Connect the other wire on the switch to the red wire and you should be good to go.

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Electrical Wiring in the Home

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"The Frank Williams School of Electrical Construction". My dear old boss is 100 ! and still going God Bless him. I started working for "Tenafly Electric" right out of high school at 19. He was tough but I learned more working for him in 8 and half years than most guys. We did mostly industrial work while doing some commercial and residential so I was fortunate to be exposed to all 3 areas of electrical construction. The guys I worked with were all good guys and I stay in touch with some of them still. Most of us went into our own buisness's which says something about the caliber of the guys I worked with. We had some interesting clients : Wella Corp. of shampoo fame, Farah Fawcett etc, I didn't buy shampoo for 10 years. It was a great place to work. Pan Am the former airline just before they went under, another great place to work, nice clean environment. C&C Metals, the largest button manufacturer in the US at that time, a not so clean environment but a very interesting place to work, lots of machine's cranking out buttons of all kinds but you had to be on your toes, it was a potentially dangerous place to be . All kinds of action going on around you.

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