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WARREN29
Dec 11, 2007, 06:26 PM
I am replacing a kitchen receptacle in a 40+ year old home with a GFI receptacle. I learned that this box also contains a light switch and also continues onto a microwave. What is the correct wiring scheme.

Washington1
Dec 11, 2007, 06:57 PM
Install all wires on the line side of the GFCI.

Q: Is the microwave on the kitchen counter top? <Just wondering>

WARREN29
Dec 11, 2007, 07:06 PM
Install all wires on the line side of the GFCI.

Q: Is the microwave on the kitchen counter top? <Just wondering>

No- over the range. I do not understand your answer. I need a complete schematic.

Washington1
Dec 11, 2007, 07:17 PM
Take a look at your GFCI receptacle. On the back it will have line, and load. You will use the line side only. *Bare copper wire goes to the green screw/ White wires will go in the silver terminal clamps/ and the black wires will go in the gold terminal clamps. In your case, it would be best to wirenut all whites together with an extra piece of white wire (6 inches long), then do the same for all the others (Black, and bare copper). *Now terminate the wires as indicated above.

Make sure you turn the power off:)

WARREN29
Dec 11, 2007, 07:22 PM
Take a look at your GFCI receptacle. On the back it will have line, and load. You will use the line side only. *Bare copper wire goes to the green screw/ White wires will go in the silver terminal clamps/ and the black wires will go in the gold terminal clamps. In your case, it would be best to wirenut all whites together with an extra piece of white wire (6 inches long), then do the same for all the others (Black, and bare copper). *Now terminate the wires as indicated above.

Make sure you turn the power off:)
I understand. What happens if they are connected to the load terminals?

Washington1
Dec 11, 2007, 07:28 PM
If the power is connected to the load side, then your GFCI want work (depending on the legitimacy
And or year it was manufactured). Yet, if the power is connected to the line side, and the remaining loads (Light and Micro) are connected to the load side. The GFCI will work properly. But, if you have a ground fault (or for some odd reason someone trips the GFCI), the Micro and lights will go off. The GFCI is basically a switch that turns off all down stream loads protected by it.

By today's standards, your install is a code violation.

WARREN29
Dec 11, 2007, 07:32 PM
If the power is connected to the load side, then your GFCI want work. Yet, if the power is connected to the line side, and the remaining loads (Light and Micro) are connected to the load side. The GFCI will work properly. But, if you have a ground fault (or for some odd reason someone trips the GFCI), the Micro and lights will go off. The GFCI is basically a switch that turns off all down stream loads protected by it.

By todays standards, your install is a code violation.
The light is a secondary light over the sink. What is the violation and how should it be wired?

Washington1
Dec 11, 2007, 07:45 PM
It's a violation only because you are not allowed to serve any other loads off the kitchen's small appliance circuit [as required per NEC 210.11(C)(1)] per NEC 210.52. Now, if you can pull in a new circuit for the micro/hood, and jump power from a lighting circuit near-by (to serve your kitchen light), then this would be best. Yet, this is not something I haven't seen before in older homes. We are allowed to keep some things the way they are based on past code, and rulings from the AHJ. Now, if this is a newly installed micro/hood (assuming it's a combination appliance), then a new wire should be pulled to the micro location.

Any way, I've seen older homes with kitchen receptacles serving garage and bath receptacles in older homes. Heck, I've seen one circuit serving an entire house :(

It's crazy, yet this is why electrical standards have changed, and are changing on an ongoing bases (Not to mention to line the pockets of corporate seats)--- It's to insure safety of people and property.

>Please note, that I did not get in detail above, just brushed on a few things<

ballengerb1
Dec 11, 2007, 08:19 PM
You should also consult the manual for your microwave. Not every appliance likes GFCI. Washington has given you totally asome answers here. We need to see more of him here on the desk.

WARREN29
Dec 11, 2007, 08:38 PM
I replaced an existing Microwave/hood with a newer model. The only wiring changemade was replacing the receptacle with a GFCI recepacle. This is the only receptacle on this circuit. Do I have a hazard?

Washington1
Dec 12, 2007, 08:24 PM
You should also consult the manual for your microwave.I agree! Some manufactures require their appliances to be on it's own circuit. If you do not follow the manufactures specifications, then you are in violation of NEC 110.3. Also, you may be in violation of local codes. In addition, your warranty is void.


Do I have a hazard? There is always a potential for hazard if codes, or manufacture instructions are not followed. If the Manufactur instruction do not call for a dedicated circuit, then there could be a usage problem--depending on the loads being served on your circuit.