Siemens Panel with Eaton Breakers

[templdl]

It appears as though yo may have run out of options thus far.
Have you thought outside of the box? Can you add a shunt trip to the exisitng breakers of install one that does?
Then use an external GF relay that would trip the ST.
As and example this is a typical D64 relay:
Ground Fault Trip Current Level 30 mA ? 6.0 Amps in 8 settings: 30mA, 120mA, 210mA,
300mA, 600mA, 2.4Amps, 4.2Amps, and 6.0Amps

http://www.eaton.com/ecm/groups/public/@pub/@electrical/documents/content/tb04900002e.pdf

Ground Fault Relays and Monitors:
Type D64 Series?Digital Ground Fault Relay System : 32.2-1
EGF Series Ground Fault Sensors: 32.2-8

 

[don_resqcapt19]

Kwired, that's the problem. You don't see the code violation, unless you have the handbook. The handbook clearly states that GFCI CANNOT be used for heating cables, aka, heat tracing. It's poorly defined in the code. You're supposed to provide a GFEP breaker that has a sensitivity of 6 ma to 50 ma, and as you know GFCI trips at 5 ma.

I'm sure it will work, but it's not really code compliant.

The handbook is not code and is not an official interpretation of the code...it is just an opinion that holds no more weight than any opinion that you will find posted on this forum. I don't think I can see providing more protection than what the code requires as a code violation, but I can see it as a potential liability to the designer and or installer if the GFCI trips and there is damage from freezing.

 

[don_resqcapt19]

Where does the code specify the trip level for Ground-Fault Protection of Equipment?

 

[Lady Engineer]

Where does the code specify the trip level for Ground-Fault Protection of Equipment?

427.22 NEC, in the handbook.

 

[don_resqcapt19]

427.22 NEC, in the handbook.

The handbook is not code. I am not aware of a defintion of GFP in the actual code. Is there one?

 

[Lady Engineer]

Actually the code allows up to 50mA, it requires 6mA minimum.

Directly from the Handbook. I've even asked the AHJ official, and he states this is something the NEC needs to revisit.

GFCI will trip at 6ma or more, correct. However, it does not pertain to equipment. From the Handbook NEC 427.22:

"This required protection may be accomplished by using circuit breakers equipped with ground-fault equipment protection, (GFEP) or an integral device supplied as part of the pipeline or vessel heating equipment that is sensitive to leakage currents in the magnitude of 6ma to 50 ma."

Skipped own to final sentence...

"It is important to understand that this is required equipment protection is NOT the same as that provided a GFCI used for PERSONAL protection that trips at 5 ma."

 

[jim dungar]

Where does the code specify the trip level for Ground-Fault Protection of Equipment?

It does not directly, the ranges come from the listing standards. I believe this is simliar to GFCI devices, where the code calls for Class A, but the 6mA number is found in an informational note directing you to UL.

 

[Lady Engineer]

The handbook is not code. I am not aware of a defintion of GFP in the actual code. Is there one?

It's has the code sections, with explanations by the Code writers, and the AHJ himself told me he flags this all the time. Do you own a Handbook? It's the code, plus explanations. Essentially, it is code.

See Article 100, where GFCI and GFEP have different definitions.

 

[Lady Engineer]

It does not directly, the ranges come from the listing standards. I believe this is simliar to GFCI devices, where the code calls for Class A, but the 6mA number is found in an informational note directing you to UL.

The regular code DOES not have the ranges, but it does explain that the differences between the GFCI and GFEP in the definitions section.

Not only is it in 427.22, it again states it for 426.28.

 

[don_resqcapt19]

Directly from the Handbook. I've even asked the AHJ official, and he states this is something the NEC needs to revisit.

GFCI will trip at 6ma or more, correct. However, it does not pertain to equipment. From the Handbook NEC 427.22:

A GFCI must trip at 6mA and must not trip below 4mA.

"This required protection may be accomplished by using circuit breakers equipped with ground-fault equipment protection, (GFEP) or an integral device supplied as part of the pipeline or vessel heating equipment that is sensitive to leakage currents in the magnitude of 6ma to 50 ma."

Where does the 6 to 50mA number come from? It is not in the code. Is it in the product standard for Ground-Fault Protection of Equipment. UL does not use the same term for this device as the code does. They call it Equipment Ground-Fault Protective Device. (EGFPD). Their information says that a EGFPD typically trips between 6 and 50mA, but does not come out and say this is a requirement of the standard. (I don't have access to the actual standard)

Skipped own to final sentence...

"It is important to understand that this is required equipment protection is NOT the same as that provided a GFCI used for PERSONAL protection that trips at 5 ma."

Yes, I understand that the code rule is trying to specify a device with a ground fault trip level higher than that of a GFCI. I still don't see how using a GFCI for a heat trace circuit would be a code violation. You are exceeding the minimum standard of the code. As I said before, I can see a potential liability issue, but not a code violation. I have seen GFCIs successfully used on heat trace many times.

I wonder if this rule is somewhat old and that current heat trace does not have as much leakage current as older heat trace did? One manufacturer says that you need to meg the heat trace with a 2500 volt megger and see a result of at least 1000 megohms. It would seem that the normal leakage current would be far below the trip point of a GFCI with that type of reading.

 

[jim dungar]

... with explanations by the Code writers, and the AHJ himself told me he flags this all the time. ....

Hand book commentary is not 'official' text and should never be cited as such by an inspector.
There have been different versions of code hand books (different authors by different publishers).

My copy of the NEC Handbook published by NFPA, specifically says " the commentary and supplementary materials in this handbook are not part of the Code and do not constitute Formal Interpretations of the NFPA..." It goes on to say they "... solely reflect the personal opinions...and do not necessarily represent the offical position of the NFPA or its technical committees".

 

[Lady Engineer]

A GFCI must trip at 6mA and must not trip below 4mA.


Where does the 6 to 50mA number come from? It is not in the code. Is it in the product standard for Ground-Fault Protection of Equipment. UL does not use the same term for this device as the code does. They call it Equipment Ground-Fault Protective Device. (EGFPD). Their information says that a EGFPD typically trips between 6 and 50mA, but does not come out and say this is a requirement of the standard. (I don't have access to the actual standard)


Yes, I understand that the code rule is trying to specify a device with a ground fault trip level higher than that of a GFCI. I still don't see how using a GFCI for a heat trace circuit would be a code violation. You are exceeding the minimum standard of the code. As I said before, I can see a potential liability issue, but not a code violation. I have seen GFCIs successfully used on heat trace many times.

I wonder if this rule is somewhat old and that current heat trace does not have as much leakage current as older heat trace did? One manufacturer says that you need to meg the heat trace with a 2500 volt megger and see a result of at least 1000 megohms. It would seem that the normal leakage current would be far below the trip point of a GFCI with that type of reading.

Umm...not sure. Why 2500VDC, per NETA we spec. 1000VDC for wires 600V or less at 1000 megohms...

Anyways, I think this was only to distinguish between equipment and personal protection and that's all. Being that the code does state GFEP and not GFCI, to me that would be a violation in itself, being that it's for two different applications.

My reasoning is that GFEP must quality with UL 1053 and GFCI must qualify with UL 943. Since UL 943 states for personnel protection, I would think a GFCI in lieu of GFEP would be invalid? I'm guessing..

 

[Lady Engineer]

Hand book commentary is not 'official' text and should never be cited as such by an inspector.
There have been different versions of code hand books (different authors by different publishers).

My copy of the NEC Handbook published by NFPA, specifically says " the commentary and supplementary materials in this handbook are not part of the Code and do constitute Formal Inteerpretations of the NFPA..." It goes on to say they "... solely reflect the personal opinions...and do not necessarily represent the offical position of the NFPA or its technical committees".

However, this still gives you a guideline.

That does not rectify that GFCI and GFEP are the same, because they are not, so why would you use it for the wrong application. Like I stated above, if the code says GFEP and we get a definition from UL 1053 as for equipment, and UL 943 for a GFCI for personnel, it would not make sense to apply a GFCI for an equipment application.

 

[jim dungar]

However, this still gives you a guideline.

Which is just as valid as my opinions and commentary.

I use code handbooks regularly. I also use other references. But just because something has been published by someone does not mean I accept it as good engineering practice nor as an industry standard.


Warning, blatant personal commentary:
I find many technical authors, especially those of text books in the past 15-20yrs, to be very agenda driven and out of touch with 'industry' practices for electrical power systems.

 

[Jljohnson]

Simple Solution.... set a small sub-panel adjacent to the Siemens panel of a brand that DOES make the correct GFEP style breaker and feed the heat trace circuit from the sub-panel.

 

[don_resqcapt19]

Umm...not sure. Why 2500VDC, per NETA we spec. 1000VDC for wires 600V or less at 1000 megohms...

The following is from Raychem's Industrial Heat Trace Manual.

Procedure:
Insulation resistance testing (using a megohmmeter) should be conducted at three voltages; 500, 1000, and 2500 Vdc. Significant problems may not be detected if testing is done only at 500 and 1000 volts. ...
Insulation resistance criteria:
A clean, dry, properly installed circuit should measure thousands of megohms, regardless of the heating cable length or measuring voltage (0?2500 Vdc). The following criteria are provided to assist in determining the acceptability of an installation where optimum conditions may not apply. All insulation resistance values should be greater than 1000 megohms. If the reading is lower, consult Section 10, Troubleshooting Guide.

Anyways, I think this was only to distinguish between equipment and personal protection and that's all. Being that the code does state GFEP and not GFCI, to me that would be a violation in itself, being that it's for two different applications.

My reasoning is that GFEP must quality with UL 1053 and GFCI must qualify with UL 943. Since UL 943 states for personnel protection, I would think a GFCI in lieu of GFEP would be invalid? I'm guessing..

The only real difference between the two devices is the trip point. I see no code violation in providing more protection than the minimum required by the code. That being said, in your position, as the engineer of record, I would not permit the use of the GFCI. Not because it would be a code violation, but only to provide protection from liability if the GFCI would trip and there would be freeze damage.

 

[Cow]

Simple Solution.... set a small sub-panel adjacent to the Siemens panel of a brand that DOES make the correct GFEP style breaker and feed the heat trace circuit from the sub-panel.

I said that in post #6 but got skipped right over.....

Or use a regular GFCI breaker and add an alarm if it trips. Just pick something and go with it.

 

[don_resqcapt19]

One issue I have with that is that the terms that the NEC and UL uses are not the same. How does anyone know the NEC term Ground-Fault Protection of Equipment is really referring to the UL term Equipment Ground-Fault Protective Device? If that is the device the NEC intends to require then the NEC should use the same term as the product standard.

As I said before I don't have a copy of the actual standard, but the UL information that is available for free indicates that the trip for the EGFPD is "typically" between 6 and 50 mA, strongly implying (to me) that the standard does not use that language.

 

[kwired]

I said that in post #6 but got skipped right over.....

Or use a regular GFCI breaker and add an alarm if it trips. Just pick something and go with it.

I also suggested using equivelant protective device likely offered by heat trace manufacturer. Nothing says this protection has to come from the branch circuit device, just that the heating equipment must have the protection.

 

[kwired]

Lady Engineer - the hand book is nothing more than contributing authors opinions on the commentary portions.

I don't have a hard copy but following text is from PDF version of 2011 handbook. It was copied from second page of PDF file.

Important Notices and Disclaimers:​

Publication of this handbook is for the purpose of circulating information andopinion among those concerned for fi re and electrical safety and related subjects. While every effort has been madeto achieve a work of high quality, neither the NFPA? nor the contributors to this handbook guarantee the accuracy orcompleteness of or assume any liability in connection with the information and opinions contained in this handbook.The NFPA and the contributors shall in no event be liable for any personal injury, property, or other damages of anynature whatsoever, whether special, indirect, consequential, or compensatory, directly or indirectly resulting from thepublication, use of, or reliance upon this handbook.This handbook is published with the understanding that the NFPA and the contributors to this handbook aresupplying information and opinion but are not attempting to render engineering or other professional services. If suchservices are required, the assistance of an appropriate professional should be sought.NFPA codes, standards, recommended practices, and guides (“NFPA Documents”), including the NFPADocument that is the subject of this handbook, are made available for use subject to Important Notices and Legal

Disclaimers, which appear at the end of this handbook and can also be viewed at www.nfpa.org/disclaimers.

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