Meyer's Hub
- Thread starter jake91945
- Start date
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gregoryelectricinc
Senior Member
Re: Meyer's Hub
Ys, unless you are entering the box via a factory stamped KO.
Ys, unless you are entering the box via a factory stamped KO.
david
Senior Member
- Location
- Pennsylvania
Re: Meyer's Hub
No:
NEC:
225.22 Raceways on Exterior Surfaces of Buildings or Other Structures.
Raceways on exterior surfaces of buildings or other structures shall be raintight and arranged to drain.
Exception: Flexible metal conduit, where permitted in 398.12(1), shall not be required to be raintight.
Handbook commentary:
Raintight is defined in Article 100 as constructed or protected so that exposure to a beating rain will not result in the entrance of water under specified test conditions. To ensure this, all conduit bodies, fittings, and boxes used in wet locations are required to be provided with threaded hubs or other approved means. Threadless couplings and connectors used with metal conduit or electrical metallic tubing installed on the exterior of a building must be of the raintight type [see 342.42(A), 344.42(A), and 348.42].
If raceways are exposed to weather or rain through weatherhead openings, condensation is likely to occur, causing moisture to accumulate within raceways at low points of the installation and in junction boxes. Therefore, raceways should be installed to permit drainage through drain holes at appropriate locations.
No:
NEC:
225.22 Raceways on Exterior Surfaces of Buildings or Other Structures.
Raceways on exterior surfaces of buildings or other structures shall be raintight and arranged to drain.
Exception: Flexible metal conduit, where permitted in 398.12(1), shall not be required to be raintight.
Handbook commentary:
Raintight is defined in Article 100 as constructed or protected so that exposure to a beating rain will not result in the entrance of water under specified test conditions. To ensure this, all conduit bodies, fittings, and boxes used in wet locations are required to be provided with threaded hubs or other approved means. Threadless couplings and connectors used with metal conduit or electrical metallic tubing installed on the exterior of a building must be of the raintight type [see 342.42(A), 344.42(A), and 348.42].
If raceways are exposed to weather or rain through weatherhead openings, condensation is likely to occur, causing moisture to accumulate within raceways at low points of the installation and in junction boxes. Therefore, raceways should be installed to permit drainage through drain holes at appropriate locations.
michael nye
Member
- Location
- California
Re: Meyer's Hub
It is a matter of common sense approach. The Meyreys Hub is (I thought) is designed for the top of enclosures, so as the rain melting snow whatever moistue is prevented from entering the can. Now on the side, I have never installed a MH on the side of a Panel. typical Quality install, lets say emt down the side of a bldg to an LR or LB direct to the panelwith a chase nipple or close bushing or G bushing. Someone correct me if I am wrong, been slapped down before on this site and I love a chance to learn.
It is a matter of common sense approach. The Meyreys Hub is (I thought) is designed for the top of enclosures, so as the rain melting snow whatever moistue is prevented from entering the can. Now on the side, I have never installed a MH on the side of a Panel. typical Quality install, lets say emt down the side of a bldg to an LR or LB direct to the panelwith a chase nipple or close bushing or G bushing. Someone correct me if I am wrong, been slapped down before on this site and I love a chance to learn.
wayne123
Senior Member
- Location
- North Carolina
Re: Meyer's Hub
Can you use a gasketed locknut on the inside of the panel?
Can you use a gasketed locknut on the inside of the panel?
curt swartz
Electrical Contractor - San Jose, CA
- Location
- San Jose, CA
- Occupation
- Electrical Contractor
Re: Meyer's Hub
I would say yes unless your at the bottom of the can or panel so if an water enters it will be below the breakers, busses or other electrical equipment. The purpose of using 3R enclosures is to keep falling water out. If your not going to seal the penetrations you make into the enclosure you might as well use a NEMA 1 enclosure.
I would say yes unless your at the bottom of the can or panel so if an water enters it will be below the breakers, busses or other electrical equipment. The purpose of using 3R enclosures is to keep falling water out. If your not going to seal the penetrations you make into the enclosure you might as well use a NEMA 1 enclosure.
michael nye
Member
- Location
- California
Re: Meyer's Hub
Thanks for the reply, are meter main type panels rated nema 3 ?
Thanks for the reply, are meter main type panels rated nema 3 ?
- Location
- Illinois
- Occupation
- retired electrician
Re: Meyer's Hub
curt,
The standard for 3R enclosures permits water to enter the enclosure as long as it does not get on the terminations or devices. These enclosures have drain holes in the bottom. As long as you make your entries on the side at or below the factory KOs or on the bottom there is no need to provide any type of seal. A top entry will require a manufacturer suppied hub.
Don
curt,
The standard for 3R enclosures permits water to enter the enclosure as long as it does not get on the terminations or devices. These enclosures have drain holes in the bottom. As long as you make your entries on the side at or below the factory KOs or on the bottom there is no need to provide any type of seal. A top entry will require a manufacturer suppied hub.
Don
curt swartz
Electrical Contractor - San Jose, CA
- Location
- San Jose, CA
- Occupation
- Electrical Contractor
Re: Meyer's Hub
Don
That is what I was trying to say in my post above. I should have bottom part of the side instead of just bottom. The way I read David's post I don't think he feels you need a hub or seal anywhere on the side of the can.
Don
That is what I was trying to say in my post above. I should have bottom part of the side instead of just bottom. The way I read David's post I don't think he feels you need a hub or seal anywhere on the side of the can.
curt swartz
Electrical Contractor - San Jose, CA
- Location
- San Jose, CA
- Occupation
- Electrical Contractor
Re: Meyer's Hub
Michael
To answer your question, all combination service entrance devices are 3R. If you are using a semi-flush type the 3R only applies to the part of the can from the nail flanges out. The interior part is only NEMA 1.
Michael
To answer your question, all combination service entrance devices are 3R. If you are using a semi-flush type the 3R only applies to the part of the can from the nail flanges out. The interior part is only NEMA 1.
michael nye
Member
- Location
- California
Re: Meyer's Hub
I more or less was refering to surface mounted cans. When ever I see someone has used the little bit of can sticking out of the wall I get a sick feeling, just looks tacky. If I cant get to the panel by fishing flex or mc or romex ect I'll cut in an J box near the can and flex to it then pipe out of it,sorry probobly to much info
I more or less was refering to surface mounted cans. When ever I see someone has used the little bit of can sticking out of the wall I get a sick feeling, just looks tacky. If I cant get to the panel by fishing flex or mc or romex ect I'll cut in an J box near the can and flex to it then pipe out of it,sorry probobly to much info
david
Senior Member
- Location
- Pennsylvania
Re: Meyer's Hub
?DON
That is what I was trying to say in my post above. I should have bottom part of the side instead of just bottom. The way I read David's post I don't think he feels you need a hub or seal anywhere on the side of the can.?
Curt
The question was specific it ask about a hub on the side of the box. As I stated the answer is no, you do not need a hub to enter the side of the box. Should you take precaution to prevent the entry of water to the enclosure, yes. In trying to prevent the entry of water you must not compromise the ground fault path.
If threaded conduit enters the side of the box and you use a gasket behind one of the lock nuts ether inside or out side I would want you to bond with a bonding type locknut. If however you used caulking after the conduit was complete I don?t see how this would compromise the equipment ground, it might even prevent rust where the conduit is secured to the enclosure. I think the same line of reasoning would apply to factory box connectors that make up the ground fault path.
?DON
That is what I was trying to say in my post above. I should have bottom part of the side instead of just bottom. The way I read David's post I don't think he feels you need a hub or seal anywhere on the side of the can.?
Curt
The question was specific it ask about a hub on the side of the box. As I stated the answer is no, you do not need a hub to enter the side of the box. Should you take precaution to prevent the entry of water to the enclosure, yes. In trying to prevent the entry of water you must not compromise the ground fault path.
If threaded conduit enters the side of the box and you use a gasket behind one of the lock nuts ether inside or out side I would want you to bond with a bonding type locknut. If however you used caulking after the conduit was complete I don?t see how this would compromise the equipment ground, it might even prevent rust where the conduit is secured to the enclosure. I think the same line of reasoning would apply to factory box connectors that make up the ground fault path.
- Location
- Illinois
- Occupation
- retired electrician
Re: Meyer's Hub
Greg,
The standards are expensive. There was a section on the NEMA enclosure types in the front of the Allen Bradley catalog a few years ago.
Don
Greg,
The standards are expensive. There was a section on the NEMA enclosure types in the front of the Allen Bradley catalog a few years ago.
Don
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