Two items that may or may not exist

[mark32]

Recently at work (HD) I was asked about two items I had never heard of. One was from an hvac guy, he wanted the "Big" 30a cartridge fuses so they'd fit in a 60a disconnect. I told him I surely didn't sell such an item and had never seen one. I told him to get those fuse adapters so he could use the typical 30a in a 60a disconnect, but he replied it wouldn't pass inspection and that he'd just pick them up at the supply house.

The other item inquire was from an electrician from another country. He asked me for what essentially is, is a breaker with two sets of terminals, a line and load. The application for this item is for a multi-family service. You'd have the meters feed into this enclosure that had no buss. These breakers are just mounted to the enclosure and you'd terminate the meter conductors to the line side and the the conductors going up to the appropriate apt would go to the load side. At first I thought the guy was out of his mind but towards the end of the conversation I believed him. He forgot what they called them back in Jamaica, but he uses them all the time in NY city. I've been in the trade over 15 years and on this site for 9 and I've never seen one, or heard anyone speak of such a breaker, nor posted a pic of one.

Any help with these two items? I really don't think such a fuse exists and would you really fail an inspection using fuse adapters? And what would this breaker be called and do you use them often???

 

[fmtjfw]

The fuses are, I believe 35A fuses that fit a 60A holder.

Breakers that have both line and load terminals exist, HD just doesn't sell them. I have some that fit in Wiremold 3000 and 4000? with screw terminals on both line and load side.

 

[PetrosA]

I don't remember whether they make those 30A fuses or not. It's been decades since I've seen a fuse box with pullouts but I do remember that most times there were only two pullouts - one for the main fuses and a second for the range, both above 30A fuse size. The breaker is something they definitely make. Instead of bolting to or plugging onto a busbar it has terminal lugs on either end and is often seen in disconnects.

 

[kwired]

The fuses are, I believe 35A fuses that fit a 60A holder.

Breakers that have both line and load terminals exist, HD just doesn't sell them. I have some that fit in Wiremold 3000 and 4000? with screw terminals on both line and load side.

35 amp fuses are physically the same size as a 60 amp fuse - but getting back to the OP they are not 30 amp fuses they are 35 amp fuses.

 

[kwired]

I looked at the Bussman fuse site, did not search real hard but found no such 30 amp fuse in a 60 amp cartridge size.


As far as breakers with lugs on both line and load - that is nothing uncommon at all. You will see limited use of such breakers in dwellings but get into the commercial and industrial applications and they are more common then many realize. If you have a motor control center with circuit breakers for disconnects in each bucket - they are likely ones with lugs on each end. If you have a single breaker in an enclosure for any reason it is likely one of this style. In dwellings the most common application is likely in HVAC equipment, particularly air handlers with electric heat.

If you get into commercial/industrial panelboards - your branch breakers are either plug on or bolt on but often the main breaker is a breaker with lugs on both ends, or is one that constructed the same with lug adapter kit installed to convert to the panel bus. I have ordered many Square D panelboards that had to be field assembled and that is what they send you, a main breaker with lugs on both ends and an adapter kit to adapt that breaker to fit the bus of the panelboard.

 

[petersonra]

I use a fair number of Square D QOU circuit breakers. They are inexpensive and will fit in a panel board or on a DIN rail. I use them on DIN rail a lot. They have both line and load terminals.

 

[kwired]

I use a fair number of Square D QOU circuit breakers. They are inexpensive and will fit in a panel board or on a DIN rail. I use them on DIN rail a lot. They have both line and load terminals.

The inexpensive part likely depends on where you purchase them from. If you find a HVAC supplier that sells air handlers that use these they are likely less (and probably even in stock) than they are at the electrical supply house that handles Square D.

 

[petersonra]

The inexpensive part likely depends on where you purchase them from. If you find a HVAC supplier that sells air handlers that use these they are likely less (and probably even in stock) than they are at the electrical supply house that handles Square D.

How much does a typical HVAC supplier charge for this $6 part?

 

[kwired]

How much does a typical HVAC supplier charge for this $6 part?

Where do you get a QOU breaker for $6. I don't know what an HVAC supplier charges, but figured if it is a common replacement part for the air handlers they sell they may actually have a better rate than a electrical supply house has. Last time I wanted a QOU (2 pole) breaker I think it was at least going to be about $50 from the electrical supply house.

 

[jim dungar]

really don't think such a fuse exists and would you really fail an inspection using fuse adapters?

I know a 30A 600V fuse is the diameter as a 60A 250V one, but their lengths are different.

Adapters are the correct code compliant method.

 

[kwired]

pictures of breakers with lugs on both line and load end

Most of them are result of a search of a particular Square D model but many other breakers ended up in the result.

 

[petersonra]

Where do you get a QOU breaker for $6. I don't know what an HVAC supplier charges, but figured if it is a common replacement part for the air handlers they sell they may actually have a better rate than a electrical supply house has. Last time I wanted a QOU (2 pole) breaker I think it was at least going to be about $50 from the electrical supply house.

I don't recall ever using a 2 pole QOU. Most are 10Amp single pole.

 

[mark32]

Many thanks for the help. I figured the hvac guy was incorrect in all accounts but the breaker guy got me curious. Thanks for the link kwired, am I correct in saying those breakers are rarely spoken of either here are on ET? I really feel out of the loop on this one. I worked commercial for 2-3 years but mainly ran pipe, which I honestly enjoyed and still do. At the time though, my heart wasn't 100% into the trade so I didn't seek out other installs going on - onsite or try to learn, which I regret now. I would love to wire a transformer or a VFD. I also don't know jack about buss duct.

 

[broadgage]

Circuit breakers with screw terminals for line and load are available in the UK.
Mainly used for building into utilisation equipment or machines rather than for use in panel boards.

Some types are suitable for DC at reduced voltages.
I have installed many of these in off grid homes for 12 and 24 volts DC.

 

[kwired]

I don't recall ever using a 2 pole QOU. Most are 10Amp single pole.

Then you likely have just been seeing them used as the overcurrent protection for maybe a control circuit in most cases. They are listed in the catalog for every standard size from 15 to 70 amps (including 10 amp) for single, double and three pole @ 10kAIC, and all standard sizes between 15 and 60 amp in 1 and 2 pole @ 22kAIC and 15-30 amps in 3 pole @ 22kAIC.

I have seen them mostly in 25, 30, 50 and 60 amp 2 pole units in single phase air handler units, size usually depends on the heating element, though sometimes they put 60 amp on anything even if it could be less. For the past 10 years or so seems like most have switched to using other brands of similar devices with lugs on both ends - mostly been seeing Siemens breakers for this purpose more recently.

 

[kwired]

Many thanks for the help. I figured the hvac guy was incorrect in all accounts but the breaker guy got me curious. Thanks for the link kwired, am I correct in saying those breakers are rarely spoken of either here are on ET? I really feel out of the loop on this one. I worked commercial for 2-3 years but mainly ran pipe, which I honestly enjoyed and still do. At the time though, my heart wasn't 100% into the trade so I didn't seek out other installs going on - onsite or try to learn, which I regret now. I would love to wire a transformer or a VFD. I also don't know jack about buss duct.

I would guess they are talked about more then you realize, they just are not specifically pointed out that they are a breaker with lugs on both ends as that fact generally isn't always important to the question or topic. If it doesn't plug on or bolt on to a panelboard bus - it is likely a breaker with lugs on both ends, or same build with adapter to fit something specific, and would be more common in larger frames though the earlier mentioned QOU series or other similar from other manufacturers are pretty common in certain items like the mentioned HVAC units.

 

[norcal]

I don't recall ever using a 2 pole QOU. Most are 10Amp single pole.

I have a 3 pole QOU molded case switch, w/ DIN rail mounting, they do come in all flavors, also think some have a 48 VDC rating too.

 

[mark32]

I would guess they are talked about more then you realize, they just are not specifically pointed out that they are a breaker with lugs on both ends as that fact generally isn't always important to the question or topic. If it doesn't plug on or bolt on to a panelboard bus - it is likely a breaker with lugs on both ends, or same build with adapter to fit something specific, and would be more common in larger frames though the earlier mentioned QOU series or other similar from other manufacturers are pretty common in certain items like the mentioned HVAC units.

Well said kwired, thanks again.

 

[kwired]

I have a 3 pole QOU molded case switch, w/ DIN rail mounting, they do come in all flavors, also think some have a 48 VDC rating too.

Actually from what I see on pages 7-2 and 7-3 in the current catalog all of the QO and QOB series (the basic 10kA rated and non specific types such as GFCI/ AFCI and some others) are all rated for 48 VDC @ 5kA interrupt rating.

The QO-U series are actually all rated for 60 VDC.