Thread: Need a little help please.

Need a little help please. Dishwasher and Garbage disposal. Outlet is under the sink on the wall. The units were on the GFCI Adjacent to the sink above the counter top. if you run one of the units its OK but if you run the 2 together the GFCI Tirps...

Can you think of cause or is this just an incorrect install?

Best

Ron
Santa Rosa California Home Inspection - Exterminating & Thermal Imaging

Just speculation
Each unit has a small amount of leakage, not enough to trip the GFCI, but together they are enought to trip it.

Motor loads.

Most times the duplex outlet is split with two separate hot and one neutral. Is there a chance that someone tried to put this on a GFCI?

Originally Posted by Ron Bibler

if you run one of the units its OK but if you run the 2 together the GFCI Tirps...

Can you think of cause or is this just an incorrect install?

Originally Posted by Rick Cantrell

Each unit has a small amount of leakage, not enough to trip the GFCI, but together they are enought to trip it.

Correct.

Motor loads will not trip a GFCI as a GFCI does not trip on overcurrent, only ground fault current.

Running both and tripping the GFCI means they BOTH have a problem which should be addressed.

The least expensive way to address this (but not the BEST way) is to separate them from the same GFCI, but, knowing they each have leakage, install each on its own GFCI.

The BEST way to correct that is to replace both appliances as they are both leaking. If the appliances are "old" (say older than 20 years or so) they both need replacing anyway. If the appliances are "not that old", then they should have been manufactured to the newer standard which does not allow for that much leakage (the current standard for leakage is, as I recall, 0.5 ma), and being as they are both tripping a 5.0 ma GFCI device together, that means their total leakage is WAY over the allowable limit of 0.5 ma.

Also consider this: The GFCI may be defective and may be tripping way too low. Possible. If you have a SureTest digital the GFCI test function will show you what it tripped at.

RB I am not seeing in the code where it requires the Disposer or the dishwasher to be GFCI protected within a dwelling unit. NEC 210.8 says receptacles serving the kitchen counter.
Dishwasher should be on dedicated branch circuit and not on with the Small appliance circuit serviing the kitchen counter due to the 50% load requirement. The disposer is usually connected with the dishwasher since it is a non continuous load. Neither of these require GFCI protection the way I interpret the code.

Originally Posted by Todd Johnson

RB I am not seeing in the code where it requires the Disposer or the dishwasher to be GFCI protected within a dwelling unit.

They are not required to be, however, they are, and being so has revealed a problem which would not otherwise have been revealed.

The disposer is usually connected with the dishwasher since it is a non continuous load.

Usually, each will have its own circuit in newer homes, in older homes they were not wired as such.

Neither of these require GFCI protection the way I interpret the code.

See my comment above - not required, but being as they are a problem has been exposed.

JP I agree with you. I was indicating that a repair could be made by eliminating the GFCI protection for those pieces of equipment. Many times Motors will have Back EMF, or a leaky capacitor that will cause a problem like this, especially when the equipment is older. This does not eliminate the total problem but if the equipment was never GFCI protected they would never know it existed. It could be repaired as you suggested by simply replacing a Defective or weak GFCI receptacle.

I appreciate your knowledge in the codes. I am always atempting to learn more about the code and the safety practices which it provides.

Originally Posted by Todd Johnson

JP I agree with you. I was indicating that a repair could be made by eliminating the GFCI protection for those pieces of equipment. Many times Motors will have Back EMF, or a leaky capacitor that will cause a problem like this, especially when the equipment is older. This does not eliminate the total problem but if the equipment was never GFCI protected they would never know it existed. It could be repaired as you suggested by simply replacing a Defective or weak GFCI receptacle.

I appreciate your knowledge in the codes. I am always atempting to learn more about the code and the safety practices which it provides.

This home is only 5 years old.

Best

Ron
Santa Rosa California Home Inspection - Exterminating & Thermal Imaging

Originally Posted by Todd Johnson

JP I agree with you. I was indicating that a repair could be made by eliminating the GFCI protection for those pieces of equipment.

Todd,

And I was agreeing with you.

Then ... I was pointing out that tripping the GFCI indicates a problem with both of them, well, okay, it could be one of them is leaking A LOT and the other one just enough to bump the leakage up to the GFCI trip point.

Originally Posted by Ron Bibler

This home is only 5 years old.

Then they really should have added separate circuits for the garbage disposer and the dishwasher at the time of construction.

Maybe those circuits are there and something is wired wrong in that GFCI box?

Originally Posted by Jerry Peck

Then they really should have added separate circuits for the garbage disposer and the dishwasher at the time of construction.

Maybe those circuits are there and something is wired wrong in that GFCI box?

Sounds vaguely familiar .

Most times the duplex outlet is split with two separate hot and one neutral. Is there a chance that someone tried to put this on a GFCI?

Originally Posted by Vern Heiler

Most times the duplex outlet is split with two separate hot and one neutral. Is there a chance that someone tried to put this on a GFCI?

Originally Posted by Jerry Peck

Then they really should have added separate circuits for the garbage disposer and the dishwasher at the time of construction.

Maybe those circuits are there and something is wired wrong in that GFCI box?

Originally Posted by Vern Heiler

Sounds vaguely familiar .

There you go again, Vern ...

Nope, not even remotely familiar as I am not referring to doing what you said, I am referring to a DIFFERENT scenario in which they screwed things up.

But thanks for checking on me anyway.

Originally Posted by Jerry Peck

There you go again, Vern ...

Nope, not even remotely familiar as I am not referring to doing what you said, I am referring to a DIFFERENT scenario in which they screwed things up.

But thanks for checking on me anyway.

I didn't say to "do" anything.

Originally Posted by Jerry Peck

Then they really should have added separate circuits for the garbage disposer and the dishwasher at the time of construction.

Kind of OT but I'm going to disagree here. Both on a 20A circuit absolutely fine. I do this all the time and it is never a problem. My own are also wired this way.
Neither is a continuous load either.

The main problem with this is that the house is only 5 years old and they are wired to a counter top GFI.

I also don't think they both have a problem since neither trips the GFI individually. If it trips immediately upon turning on the other appliance I say something is wired wrong.

Not that it matters MUCH but I believe the Standards for Safety for these appliances limits the leakage current to 0.75 mA not 0.5 mA.

The Dishwasher and/or Disposal cordsets must be factory installed, or supplied by the manufacturer from a Listed kit to meet the Listing requirements.

Is the dishwasher installed or is it a portable model (and unconverted to fixed installation)?

I see the main problem as that either of these fixed appliances (assuming the dishwasher isn't a portable one and is supplied by the plumbing system not a faucet connection) are sharing a circuit with another receptacle. especially one of the SA circuits.

I don't have to believe. I KNOW.

The standard for most cord and plug connected appliances is 0.5 ma ground fault leakage MAXIMUM.

Most of the research for that 0.5 ma leakage limit was based on the human startle sensation to electrical current and was done by UL back in the 1960s.

For whatever it's worth, and I'll grant you it might not be much, AFCIs have GFCI circuitry built into them, and, it is set at 20 mA rather than the 5 mA a GFCI receptacle or breaker are. I suspect that the reasons for this are that with multiple inductive loads and things like switching power supplies someone realized that the 0.5 mA threshold was going to be frequently exceeded and cause nuisance tripping. Were this not an issue we could just set the GFCI part of an AFCI at 5mA and just forget about separate GFCIs on anything. (actually, Eaton makes the old branch feeder style AFCI in the double listed configuration - AFCI/GFCI)

Although cord connected appliances are limited to certain levels of leakage there is no mechanism in a GFCI receptacle to detect what each connected appliance is leaking - it just trips when the total exceeds 5 mA.

So, both of these appliances may be just fine (both chugging along at a leakage level of, say, 3.5 mA) and the wiring is probably "technically" OK in spite of violating code by using a small appliance counter circuit. These appliances were designed to be hard wire grounded as their safety protection and really have no business on a GFCI protected circuit. If they are installed this way they each need to be on a separate one (GFCI) as the additive leakage is tripping the GFCI

The fix here (to prevent GFCI tripping) is to take the supply to the disposer and dishwasher off the load side of the GFCI and get it on the line side, making sure they are properly grounded. Of course the right thing to do is get them both off the small appliance counter circuit.

Originally Posted by Bill Kriegh

So, both of these appliances may be just fine (both chugging along at a leakage level of, say, 3.5 mA)

That what I have been pointing out, if an appliance is "chugging along at a leakage level of, say, 3.5 mA" that the appliance *is not "just fine" as the level of leakage allowed for most cord and plug connected appliances is only 0.5 mA. If they have 3.5 mA leakage, they have WAY too much leakage in them.

Well, I applogize. I had
several decimal placement errors in my post. They got fixed.

Jerry, I believe that the 5mA figure is what GFCIs trip at, not 0.5

Sensation
Tingle sensation occurs at about 0.25mA to 0.5mA for an adult female and between 0.5mA and 1mA for an adult male.

Uncomfortable sensation
Current greater than 1mA to 2mA is very uncomfortable to either gender.

Maximum let-go level
The maximum let-go threshold level for a female is about 9mA and about 15mA for a male.

Typically, you loose the ability to let go of things when there is a current present of somewhere between 7mA and 15mA

You usually wind up with heart issues when 75 mA is present for over half a second or 500 mA is present for more than .2 second. A lot of things have to be just right for you to walk away from this kind of shock.

The 20 mA level set in an AFCI MIGHT keep you from getting dead, but don't count on it.

Originally Posted by Jerry Peck

I don't have to believe. I KNOW.

The standard for most cord and plug connected appliances is 0.5 ma ground fault leakage MAXIMUM.

Most of the research for that 0.5 ma leakage limit was based on the human startle sensation to electrical current and was done by UL back in the 1960s.

Which has NOTHING to do with the topic at hand, since the Standard which contains that limit doesn't apply to either of the appliances in question.

Originally Posted by Jerry Peck

That what I have been pointing out, if an appliance is "chugging along at a leakage level of, say, 3.5 mA" that the appliance *is not "just fine" as the level of leakage allowed for most cord and plug connected appliances is only 0.5 mA. If they have 3.5 mA leakage, they have WAY too much leakage in them.

Its amazing what you THINK you KNOW, because you're wrong.

Dishwashers, Household (UL Category DMIY under "Cleaning Machines DMDT ) {and those that have "sanitizing" modes further categorized under "Residential Dishwashers" (TSXU) under Sanitation, Food Service Equipment TSQS) which are further investigated}, are subject to ANSI/ASSE Standard No. 1006. "Household Dishwashers" the basic Standard used to investigate products in that category is ANSI/UL 749 "Household Dishwashers." Section 13 pertains to "Leakage Current". Additional Information applicable see Electrical Equipment for Use in Ordinary Locations (AALZ) and Plumbing and Associated Products (AAPP) {and for sanitation and public health requirements TSXU products are further investigated in accordance with NSF/ANSI 184 "Residential Equipment - Residential Dishwashers" and additional information at Heating, Cooling, Ventilating and Cooking Equipment (AAHC) and Plumbing and Associated Products (AAPP).

"Garbage Disposers" in the home may be categorized under "Waste Disposers" (ZDHR), they may be further categorized under "Waste Disposers, Pulper Type" (ZDIB) marked for Household or Residential Use; "Waste Disposers, Replacement Type, Household" (ZDIF); or Waste Disposers, Sink Mounted (ZDII).

Power supply cords intended for use with waste disposers are investigated to ANSI/UL 430, "Waste Disposers", and covered under Waste Disposers, Sink Mounted (ZDII). Only those power-supply cords that have been investigated to ANSI/UL 430 are permitted to be marked "Garbage Disposal Cord" or the equivalent. "Cord Sets and Power-Supply Cords" (ELBZ) are not sufficient to be used for "Waste Disposers".

Waste Disposers, Sink Mounted marked for "Household Food Waste Disposers" have been determined to comply with the latest edition of ANSI/ASSE 1008, "Plumbing Requirements for Household Food Disposal Units" which covers household food waste disposers installed in a kitchen sink, supplied with water from the sink faucet, and discharged into the plumbing drainage system (category ZDII). Disposers are investigated to
ANSI/UL 430 "Waste Disposers" pertains to ZDHR, ZDII and ZDIF. It too has its own specifications regarding current, leakage/ing.

Your "KNOWING" or implying that UL 101 "Leakage Current for Appliances" applies to the categories applicable to this post string are flat-out wrong. Although STDs have proposed since either 06 or '07 to change/replace the leakage current requirements for Standard UL 749 (Dishwashers) and instead include a reference to the Standard for Leakage Current for Appliances (UL 101), the Standard (UL 749) has not been heretofore changed in that regard. Disposers (UL 430) have their own limitations in the Standard relating to Household/Residential use and that has also not been changed.

Acknowledging you were never a chief compliance inspector, your inability to "play nice with others", and your egomania, it should not be surprising you can't grasp even the most obvious implication let alone more advanced critical thinking.

You repeatedly question documented UL Staff opinion, Engineering Reports, and published reference materials, which are incorporated into "the code". It wouldn't surprise me that you were/are unwelcome at IAEI.

That you are unwilling or unable to USE, reference, or even acknowledge the existance of the White Book editions, nor the other Guides, is sad for one claiming to have been successfully employed as an AHJ code inspector.

Regarding UL 101: "The values in this Standard do not provide protection against minute currents which could cause ventricular fibrillation if applied directly to the heart, as via a heart catheter." Reference: " WEINBERG, D. I., J.L. ARTLEY, R.E. WHALEN, H.D. McINTOSH. Electric Shock Hazards in Cardiac Catheterization, An Engineering Analysis. Electrical Engineering 82:30-35. 1963 (American Institute of Electrical Engineers now the Institute of Electrical and Electronic Engineers)."

I have previously pointed out the Code conflict with installed Disposer and/or Dishwasher to the shared small appliance circuit, and followed up regarding the cord/plug questions.

Originally Posted by Bill Kriegh

Jerry, I believe that the 5mA figure is what GFCIs trip at, not 0.5

Bill,

The GFCI trips at 5.0 mA plus or minus 1.0 mA.

The allowable leakage for most cord and plug connected appliances is only 0.5 mA.

That means that an appliance with a ground fault leakage of 3.5 has 7 times the allowable leakage, while still being within the leakage allowed before a GFCI trips.

Originally Posted by Bill Kriegh

Well, I applogize. I had
several decimal placement errors in my post. They got fixed.

Jerry, I believe that the 5mA figure is what GFCIs trip at, not 0.5

Sensation
Tingle sensation occurs at about 0.25mA to 0.5mA for an adult female and between 0.5mA and 1mA for an adult male.

Uncomfortable sensation
Current greater than 1mA to 2mA is very uncomfortable to either gender.

Maximum let-go level
The maximum let-go threshold level for a female is about 9mA and about 15mA for a male.

Typically, you loose the ability to let go of things when there is a current present of somewhere between 7mA and 15mA

You usually wind up with heart issues when 75 mA is present for over half a second or 500 mA is present for more than .2 second. A lot of things have to be just right for you to walk away from this kind of shock.

The 20 mA level set in an AFCI MIGHT keep you from getting dead, but don't count on it.

The GFCIs we are discussing trip between 4 and 6 mA. What we don't know is the date of manufacture of the GFCI in question, and the Standard for Safety (UL 943) has had several significant revisions of late (previously pointed out in a prior post), however the 4-6 mA has been constant.

The leakage current amounts discussed have been less than 1 mA.
JP is flat out wrong regarding the permitted leakage current for the two appliances which were the topic of the original post on this discussion.

What has been overlooked is the delay (shift) that can occur with a start up of either these appliances especially the disposal motor.

We do not know the rating of either appliance, if the cord sets are original to manufacture, or the correct and listed cord sets added in the field, nor if the dishwasher is a portable one or if it is installed.

UL 943, Ground Fault Circuit Interrupters (GFCI)s are not necessarily the same as an Appliance Leakage-Current Interrupter (ALCI).

UL 943B Appliance Leakage-Current Interrupters (ALCI) trip when the current to ground reaches a value in the range of 4 - 6 mA. Here's a direct quote from the Scope:

Originally Posted by Scope for UL 943B as appears and copyrighted on ul.com 09/17/2009 and used with permission

Appliance Leakage-Current Interrupters

1 These requirements cover appliance leakage-current interrupters (ALCIs), intended for use only in 2- or 3- wire alternating-current circuits wherein one of the wires is grounded in accordance with the National Electrical Code, ANSI/NFPA 70. They are intended to interrupt the electric circuit to the load when a fault current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit. An ALCI trips when the current to ground reaches a value in the range of 4 - 6 mA.

1.2 These requirements cover 2-wire appliance leakage-current interrupters for use only in cord-connected appliances intended for connection to alternating-current circuits of 250 V or less. An additional ground conductor may be provided. They are not to be provided with a general-purpose outlet receptacle, cord-connector body, or similar devices. Devices complying with these requirements are acceptable for use as components in an end product where the acceptability of the combination is to be determined.

1.3 The acceptability of an appliance leakage-current interrupter in any particular application depends upon its ability to be used continuously under the conditions that prevail in actual service. Accordingly, for a particular application, an appliance leakage-current interrupter may be affected by the requirements for the equipment it is used in, and it may be necessary to additionally evaluate features or performance characteristics that are not specified in this standard.

1.4 This standard does not cover ground-fault circuit-interrupters, which are covered by the Standard for Ground-Fault Circuit-Interrupters, UL 943

Originally Posted by H.G. Watson, Sr.

your inability to "play nice with others",

My inability to "play nice with others" make me look like a warm fuzzy Teddy Bear when compared with your inability to "play nice with others" and you consistent and insistent need to derate others to try to make yourself look better.

That you are unwilling or unable to USE, reference, or even acknowledge the existance of the White Book editions, nor the other Guides, is sad for one claiming to have been successfully employed as an AHJ code inspector.

And where in there did you post the supposedly disputed leakage current allowances?

All you do is post lists of lists, touting what you think you know, yet you do not post what is relevant - actual code and standard statements with actual specifications.

You huff and you puff and you blow ... hard, but you have not be able to blow any houses down here, not even the ones made of straw, or sticks, and you huffing and puffing does not even rattle the windows of the houses made of brick. I used that child story reference to go along with your use of "play nice with others", which you so adamantly try to accuse others of doing, while ignoring your own actions - which is typical of the schoolyard bully, which is what you act like, only here you have been completely unsuccessful trying to be the bully ... no one here allows you to steal their lunch money and you simply can't stand it.

It's time to say 'call an electrician.'

There might be a problem with the appliances - or (more likely in my guess) there's a problem with the wiring. For example, different circuits are mixed up. You won't know without taking everything apart - and that's beyond the scope of a home inspection.

For the last time, UL 101 does NOT pertain to Dishwashers or Garbage Disposals. UL 749 and UL 430, respectively, do. UL 749 and UL 430 have their own limitations regarding leakage current when the appliance in question is listed for household use.

As far as your other assertions regarding single phase motorized appliance with a HP rating greater than 1/8 hp not being able to cause an older (pre August 2006 manufacture) GFCI to trip for a reason other than a ground fault is laughable.

You prove what you claim to KNOW....the onus is on YOU. I already DIRECTED YOU TO READ THE WHITE BOOK AND THE STANDARD FOR SAFETY UL 101. UL 101 doesn't apply to either appliance (Dishwasher nor Garbage Disposal).

Don't like it? Lobby for a change to the ANSI Standards, Write to UL to change the Standards. In the meantime, not being employed by an authority having jurisdiction, you have no authority to re-write either the Standards, the Listings, nor the Codes.

Get a clue as to what UL 943B pertains to.

Without knowing if the Dishwasher is indeed listed for Household use, and/or if it is listed as a Sanitizing one;

And without knowing if the Disposer is indeed listed for Household Use, nor which category (replacement or not);

Can't be specific. Depends on the Category, the Labeling, the Listing, and the Date of Manufacture.

Originally Posted by H.G. Watson, Sr.

For the last time,

Unfortunately it is not, and will not be, the last time you rant on as you do without posting the specifics of which you state are correct and yet off no proof.

Unfortunately, that is what you have done since you first started posting here and is undoubtedly what you will continue to do (based on what you have continued to do).

"For the last time ... " ... we could only hope for such a time.

Read the dang Standards Jerry Peck the Proof is in the Pudding as they say.

The onus is upon you to PROVE that the leakage current is limited to 0.5 MA for Dishwashers, Household or Waste Disposers for Household Use.

They aren't and you can't. That's what you claimed - PROVE IT. I won't hold my breath waiting, because of course WHAT YOU SAID IS NOT TRUE.

You made the claim, claimed it was relevant, its up to YOU TO PROVE IT.

My Dear Dear Watson,

It is really a shame you cannot, or choose not to, read and comprehend what you have read.

No wonder you incessantly rant on.