Client wants fuses no breakers, new service any ideas

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scottp628

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looking for a manufacturer for a new fused distribution panel, single or three phase if one is still being made, Edison or plug style, not a circuit breaker panel for a small factory/research lab.
 
I see no practical reason for this request.
However, you might look at Cooper/Bussmann. They make a fusible lighting panel.
 
jim dungar said:
I see no practical reason for this request.
However, you might look at Cooper/Bussmann. They make a fusible lighting panel.
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Yea the fist time they have a brown out or power failure and stuff blows fuses on start up he'll be singing the blues.

Does this company have a full time service tech.
 
Fresh Market grocery stores use fusible panels in some of their stores, 20 amp branch circuits, it's been a while since I've seen one, but it kinda looks like a regular breaker, but has a switch that has a fuseholder built in. I can't remember if it was Square D, or some off brand, but it would work well in your situation. Uses high AIC cartridge type fuses. 277/480 volt service.
 
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If you want loads protected by fuses you can always use supplemental fuses at the load. This is definitely the way to go if non standard breaker sizes is the protection level desired or less than 15 amps.
 
hillbilly1 said:
Fresh Market grocery stores use fusible panels in some of their stores, 20 amp branch circuits, it's been a while since I've seen one, but it kinda looks like a regular breaker, but has a switch that has a fuseholder built in. I can't remember if it was Square D, or some off brand, but it would work well in your situation. Uses high AIC cartridge type fuses. 277/480 volt service.
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For a service entrance panelboard 400A or higher look at Square D QMB fused panelboards and GE Spectra series panelboards (they are available with fuses as well as breakers). Eaton and Siemens have fused panelboards in this size range as well but I don't know the series offhand.

For 225A or less there are a handful of vendors that make fused panels that are traditionally used for UPS circuits in industrial plants: Ametek, Kinney, VTI, Filnor (the old Cleveland Switchboard Co.). These companies all use a major manufacturer's panelboard interior fitted with molded case switch branch devices that feed fuseholders off to the side. They are very wide - 30" plus. Bussmann makes a Quik-Spec fused panelboard that uses their Cube Fuse product and the Compact Circuit Protector Base - this may be what Hillbilly was talking about with a switch and fuseholder in one small unit. Bussmann will be the lowest cost and smallest, but some people do not like the components, quality, etc.
 
scottp628 said:
looking for a manufacturer for a new fused distribution panel, single or three phase if one is still being made, Edison or plug style, not a circuit breaker panel for a small factory/research lab.
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As the arc-fault protection issue came to the forefront of concern it has been argued that fuses are superior to circuit breakers in that aspect. The question of course is then: is it safer to reset a breaker or replace a fuse.
 
weressl said:
As the arc-fault protection issue came to the forefront of concern it has been argued that fuses are superior to circuit breakers in that aspect. The question of course is then: is it safer to reset a breaker or replace a fuse.
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When it comes to fuses being replaced by non electricians the breaker is probably the better choice. Otherwise if the fuse will fit in the fuseholder and it has a bigger number on it than the one that it replaced, then that is the best choice (to the person changing it).
 
kwired said:
When it comes to fuses being replaced by non electricians the breaker is probably the better choice. Otherwise if the fuse will fit in the fuseholder and it has a bigger number on it than the one that it replaced, then that is the best choice (to the person changing it).
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Sir, you're correct. I was thinking more in the line of being exposed to live parts - in the case of fuses - for one and secondly that breakers are only rated/tested to interrupt a full rated SC only once, so if you reclose it on a fault it is more likely to present a hazard than a fuse. (Although plugging a fuse onto a fault is no fun either:happysad:.
 
weressl said:
breakers are only rated/tested to interrupt a full rated SC only once, so if you reclose it on a fault it is more likely to present a hazard than a fuse.
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Are manufacturers of breakers not supplying the maintenance schedules for the breakers to follow? or Are the breakers not maintained properly by field people?
 
T.M.Haja Sahib said:
Are manufacturers of breakers not supplying the maintenance schedules for the breakers to follow? or Are the breakers not maintained properly by field people?
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The biggest problem is that we don't typically know the magnitude of the fault. However, we can make some assumptions that would support NOT changing a MCCB after any fault:

-We know from the IEEE 1584 equations that LV arcing currents are on the order of 50-60% of 3 phase bolted fault currents, and we know that most faults are arcing in nature, so we can expect the vast majority of faults to be well below the maximum short circuit current available.

-Breakers are typically purchased with an interrupting rating well in excess of the maximum short circuit current available on the system. In my plant we typically have 30-40 kA available on 480 V busses, but we have standardized on purchasing 65kA breakers in our MCC buckets for two reasons: it is recommended that the rating of the breaker exceed the available short circuit current by a 20% design margin to account for errors in the calculation, changes in motor contribution, and other variables. We have a limited number of MCC types in the plant and enjoy the flexibility of moving buckets between MCCs, so we standardize on interrupting rating so fold won't accidentally install a 42 kA device in an MCC with a calculated short circuit current of 40 kA.
 
robbietan said:
Incredibly, some places in my country would specify that main disconnects use fuses and not circuit breakers
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I don't find that suprising at all in places with high available fault current at the service equipment. In dwellings and small commercial occupancies that usually is not a problem.
 
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