Electrical interference

[kwired]

May be a dumb question, but how old is the house?
Could it be the dishwasher and ac are on the same feeder?

That kind of shouldn't matter. same branch circuit isn't acceptable though.

 

[kwired]

The Original Post stated that the Heat Pump was changed ... so it is a High Efficiency unit and is causing the interference we have been talking about.

Really is a matter of what should be changed, GFCI designs or designs of equipment that utilize high frequency high speed switching.

That and the fact NEC has overdone it in recent years IMO with some the GFCI requirements on things that don't have much of a history for having shock/electrocution incidents. IIRC the outdoor outlet requirement change that ended up including residential AC units was triggered by an incident that had missing or compromised EGC to the unit- which if we are going to use that as a reason why even require EGC's and just put GFCI protection on everything? Many other things that were added over the past 20 years to the GFCI protection list are similar - if an intact EGC is present GFCI protection really isn't needed. So guess who promotes these changes? Likely the GFCI manufacturers?

Maybe a better solution is somehow making appliances that test for presence of an EGC and lock themselves out of operation if such tests fail?

 

[ramsy]

Really is a matter of what should be changed, GFCI designs or designs of equipment that utilize high frequency high speed switching.

One advantage of RCD's is the common design for high-frequency noise, which Teslas wall chargers have used for years.

In late 2020, WWEST announced the release of the Class II RCD

Prior to WWEST, ABB & others made 50-60Hz, 230v RCD lines, that could be specified below 10mA.

That and the fact NEC has overdone it in recent years IMO with some the GFCI requirements.. ..So guess who promotes these changes? Likely the GFCI manufacturers?

The same industry that leverage their NFPA code-panel appointments, to adopt 2-Pole GFCI's, AFCI's, and SPD's, will likely block RCD devices, with intellectual property owned by competitors.

Maybe a better solution is somehow making appliances that test for presence of an EGC and lock themselves out of operation if such tests fail?

Adopting Assured Grounding at the appliance level would also solve broken Grounding prongs, often removed from the cord cap.

It would also enforce the EGC needed for motorized appliances w/ 3-prong plugs, regardless of GFCI replacement code for 2-prong outlets.

 

[don_resqcapt19]

Really is a matter of what should be changed, GFCI designs or designs of equipment that utilize high frequency high speed switching.
...

UL 943 is working on that but expect an actual standard is still at least a couple of years away, than another year or two for the manufacturers to design, test, and produce a product.

 

[winnie]

Yes, but all the discussion of GFCIs, past the common issue of their responding to electrical noise, is irrelevant to the OP.

The lights flickering and the dishwasher responding to noise are not a GFCI issue.

 

[ramsy]

The OP left the building, when he realized general contractors wont pay for troubleshooting

 

[ramsy]

UL 943 is working on that but expect an actual standard is still at least a couple of years away, than another year or two for the manufacturers to design, test, and produce a product.

Siemens may have circumvented that process by licensing RCD Tech for their 2-Pole GFCI, designed for problematic Pentair & Hayward VFD pool motors.

 

[don_resqcapt19]

Siemens may have circumvented that process by licensing RCD Tech for their 2-Pole GFCI, designed for problematic Pentair & Hayward VFD pool motors.

I think there is someone else advertising that type of device also. As long as the device passes all of the requirements of UL 943, they can make any other design changes they want to their GFCIs. However, I don't think there was any specific re-design. I believe the fact that they functioned for the Pentair equipment was just found accidentally by the installers.

What UL 943 is working on is one that will be called GFCI-HF to account for the high frequency leakage current issue. I think, that because high frequency current is less harmful to humans, it will permit a higher trip current for the higher frequencies.

That can't be what Siemens is doing, because the current standard sets an absolute 4-6mA trip for leakage current no matter what the frequency of the leakage current may be.

 

[ramsy]

What UL 943 is working on is one that will be called GFCI-HF to account for the high frequency leakage current issue.

I see existing work with RCD's usually require an EGC connection to earth, and operate at 230v.

 

[mtnelect]

I don't know how many of you have read my Post #8, but there are a lot of low income people that have been forgotten in all of this fiasco.

 

[ramsy]

I don't know how many of you have read my Post #8, but there are a lot of low income people that have been forgotten in all of this fiasco.

Your post requires an un-secure download of a separate PDF file.

This is not a recommended practice, nor necessary with URL links, or your summary of the issue.

 

[kwired]

I don't know how many of you have read my Post #8, but there are a lot of low income people that have been forgotten in all of this fiasco.

since when has NEC ever made rules based on cost of the installation? Well at least post WWII?

If anything corporate greed been driving some the PI's and presentations to push a product in name of safety, and then we get requirement to use something that hasn't had all the bugs worked out of it yet.

 

[50 year Sparky]

Is it also the 3rd time you worked for free?

Actually the utility company paid for every hour we were there, and paid the bill for the EE with all the metering equipment.

 

[ramsy]

Actually the utility company paid for every hour we were there, and paid the bill for the EE with all the metering equipment.

Glad your back, please feel free to takes the topic where you left off.