Grounded Outlets

Homes wired prior to the 1960’s were commonly wired with a two-wired system with non-grounded outlets, unlike today’s modern wiring code which uses a  three wire grounded system. What electrical devises can be plugged into a ungrounded outlet?




Small kitchen appliance

Devises that do not have a three prong cord

What electrical equipment should not be plugged into non-grounded outlet?

Most high end electronics





Larger kitchen appliances

Devises having a three pronged cord

Older homes with existing two-wire system generally will have two slot outlets; a dangerous mistake would be to cover a two-wired outlet with a three-slot outlet. Unfortunately, there are many two slotted outlets that have been upgraded to three-slot outlets without providing a ground wire. This has no benefit, and may be misleading when plugging a three-pronged device into an upgraded but ungrounded outlet. This is called an open ground and can be devastating to your high-end electronics, equipment, and personal safety. 

There are a couple of things that can be done if your outlets are not grounded. 

The National Electrical Code (NEC) allows the following methods to update an ungrounded outlet

Replace the 2-wire outlet with a GFCI-type outlet and mark the outlet with the words “No Equipment Ground”

Install a GFI breaker in the panel marked “GFCI Protected” and “No Equipment Ground.

Replace the existing three-slot outlet with a two-slot ungrounded outlet

Replace two wired system with updated three wired system

Plugging your high-end electronics into a ungrounded outlet could cause damage to your equipment from static electricity as well as, a sudden spike in voltage such as a lighting strike. Most importantly never, plug an appliance or devise that has a three pronged cord into a ungrounded outlet, as this could cause serious electrocution if you are in contact with the device and a good ground simultaneously.

Finally, if you are unsure about your homes wiring and its safety, it is recommended that you contact a licensed electrician to inspect your homes electrical wiring system. 


By Richard Schmitz 


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