I installed a new dishwasher this weekend. In the process I discovered that the dishwasher has its own dedicated breaker, and also that this breaker does not appear to have a GFCI feature. This surprised me, given that the dishwasher brings water and electricity into close proximity with each other.
Is this a normal/safe condition, or should I hie to the nearest Home Depot and pick up a new GFCI breaker?
Mine isn’t and I’ve never seen one that was on a GFI breaker. Not that extra protection is bad, but I’ve never seen this myself.
By code, a dishwasher is not required to be protected by a GFI device. It’s not a bad idea but be aware that motors can often cause nuisance tripping on a GFI.
not required and as stated a larger motor will often trip the GFI breaker.
But it is required to be on its own dedicated circuit, which it is in this case. That goes for all kitchen appliances.
Interesting, thanks. Any idea why dishwashers are not rquired to be GFCI-protected? Is it because of the tendency for annoying motor-related tripping you mentioned, or is the hazard of water+electricity in this instance just not nearly as great as I imagine?
Water and electricity aren’t as hazardous as often portrayed in movies; a wire in a puddle won’t make it instant death if touched, especially if your body isn’t otherwise grounded or in a complete circuit (even a hairdryer in a bathtub won’t shock if it falls between you and the grounded drain/pipes, not so if you are between the hairdryer and drain). Of course, a dishwasher is typically near a lot of grounded metal so I can see a potential hazard here; most likely, the metal case being grounded along with all of the electric stuff being enclosed precludes any significant shock hazard (any leakage current would go to the grounded metal).
I’ve heard for years that motors can cause “nuisance” trips. But I’ve never heard a good explanation for it.
Since all sorts of other motors (pool, hot tub, jacuzzi) are required to be on GFI circuits, I’d say it’s not a valid claim.
I did some google searching, and it appears to be a common belief (even amongst some electricians) that motor load = GFCI nuisance trip. Even if it’s true - which I’m not convinced it is - the explanations I found were laughable. Lots of babbling about “GFCIs do not like inductive loads” and “Back EMF confuses the GFCI circuitry.”
I’m not saying it’s not an issue; perhaps some motors w/ grounded housings tend to leak excessive current to ground over time due to insulation breakdown. But I would just like to see some data to back it up.
Now that you mention it, I’ve used a bunch of tools in my basement on GFCI outlets with virtually no issue. This includes a drill press, belt sander, shop vac, table saw, orbital sander, etc. I only once briefly had an issue with the belt sander causing GFCI trips, and I’m pretty sure that was because some metal dust had gotten into the motor; a quick blast of compressed air cleared it, and the sander hasn’t caused any faults since then.
Modern GFCIs are a lot smarter about inductive loads. There shouldn’t be any problem with putting a GFCI breaker on your dishwasher, although it’s not strictly required. It certainly won’t hurt.
There is also no requirement for GFCIs on washing machines, coffee makers, water heaters etc. All are electrical appliances that use water.
GFCIs are required where the likelyhood of one standing in water while receiving a shock is high - bathrooms and your back porch for example or in your hot tub.
The understanding is that water facilitates and increases your ground potential. A GFCI will interupt power much quicker than a traditional thermal magnetic breaker which is why it is used in these situations.
In your case, it was a good thing the GFCI tripped, as it alerted you to an early problem with the belt sander. If it had not been plugged into a circuit w/ GFCI protection, the leakage to ground may have evolved to the point of becoming a hard short, and the breaker would eventually trip. But by that time significant damage will have occurred within your belt sander. Regardless, as long as the chassis/housing remained grounded, there was no danger to life or limb. In this instance, the GFCI acted as equipment protection, not human protection.