Suitable for use Only as Service Equipment

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infinity

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I have a 1000 kva transformer feeding a 3000 amp main disconnect that says "Suitable for Use Only as Service Equipment". It's been suggested that if the system bonding jumper is located in the 3000 amp gear then the installation will be compliant. Other suggestions are to remove the link between the EGC bus and the neutral bus and install the bonding jumper within the 1000 kva. Electrically either solution will work but I'm concerned about the listing, others have suggested that it really amounts to nothing more than a sticker on the equipment with some words on it, have the manufacturer change the sticker and either one works. Thoughts?
 

augie47

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I am of the opinion that electrically if you leave the system bonding jumper in the 3000 amp gear and connect your grounding electrode there also that all will be fine.

If you feel it is necessary to remove the sticker or obtain a new one to satisfy the "UL Police", so be it.
From experience when I have had to have gear updated and approved by UL to obtain a "SUSE" sticker the only "improvement" has been some buss bracing, system bond, & of course a sticker.
 

infinity

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Around here we never install the bonding jumper in the disconnect, only at the transformer so for most this would be out of the ordinary. Of all of the large mains this was the largest and the only switch that come in this way, one thought was that all of their 3000 amp main switches are only service rated.
 

don_resqcapt19

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Illinois
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I have a 1000 kva transformer feeding a 3000 amp main disconnect that says "Suitable for Use Only as Service Equipment". It's been suggested that if the system bonding jumper is located in the 3000 amp gear then the installation will be compliant. Other suggestions are to remove the link between the EGC bus and the neutral bus and install the bonding jumper within the 1000 kva. Electrically either solution will work but I'm concerned about the listing, others have suggested that it really amounts to nothing more than a sticker on the equipment with some words on it, have the manufacturer change the sticker and either one works. Thoughts?
I thought that the difference between listed as "suitable for service equipment" and listed as "suitable for use only as service equipment" was that the main bonding jumper was permanently installed and not field removable in the equipment listed as "suitable for use only as service equipment". I don't think I have seen any equipment other than small panelboards with a "suitable for use only as service equipment" listing.
 

infinity

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I thought that the difference between listed as "suitable for service equipment" and listed as "suitable for use only as service equipment" was that the main bonding jumper was permanently installed and not field removable in the equipment listed as "suitable for use only as service equipment". I don't think I have seen any equipment other than small panelboards with a "suitable for use only as service equipment" listing.

I didn't look inside of the gear but I'm guessing that in this size equipment it's nothing more than a bolted piece of buss between the EGC and neutral buses. Ill have to look inside to see, in the mean time here's a photo of the switch:


IMG_20141007_141725.jpg
 

GoldDigger

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Worst case an "only" panel can be converted by adding an insulated bar for the neutrals. If the additional bar is a listed accessory, you should be able to get a new label too. :)
 

don_resqcapt19

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Illinois
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I didn't look inside of the gear but I'm guessing that in this size equipment it's nothing more than a bolted piece of buss between the EGC and neutral buses. ...
I looked at the UL marking guide and the "suitable only for use as service equipment" does not mean what I thought it did. I thought that the marking meant that the main bonding jumper was not field removable. I know that is the case for some panel boards. However the UL marking guide just says:
A panelboard with the neutral factory-bonded to the enclosure is marked "Suitable only for use as service equipment".
It appears that if the factory installs the main bonding jumper that the equipment would be marked "suitable only for use as service equipment". That does not make a lot of sense to me...if the factory installed main bonding jumper is field removable, why would the equipment be marked that way? I understand it for the small panelboards where the neutral is riveted to the enclosure, but not where the main bonding jumper is removable by taking a bolt or screw out.

Why would a manufacturer even want that listing where it limits the application of the equipment and actually costs more than shipping the main bonding jumper loose with the equipment?
six main disconnecting means.?
 

jumper

Senior Member
Why would a manufacturer even want that listing where it limits the application of the equipment and actually costs more than shipping the main bonding jumper loose with the equipment?

And why would I want to order a piece of equipment with this limitation?

I see no advantage. It would seem to me that a standard SUSE listing gives me better options.
 
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