Bolt-on breake, why

[Toros]

Hi,
why 277v circuit breakers ara bolt-on,
why not snap-in??

 

[norcal]

SQ D has 277V plug-in breakers, or at least they did.

 

[jim dungar]

SQ D has 277V plug-in breakers, or at least they did.

Effectively their whole I-Line series is 'plug-in'.

(It was their old EH line that was 277V plug-in)

Seriously, I beleive it is the market place that does has driven the product offering.

 

[shortcircuit2]

Hi,
why 277v circuit breakers ara bolt-on,
why not snap-in??

I was told that higher fault-current rating of the equipment will dictate how the equipment is constructed. So the higher the fault-current rated equipment will have more support for the bussing and bolt-in style breakers.

Although the I-line equipment is plug-on, it has this feature design:


Breaker connections
are ?blow-on? type.
Under high-level fault
conditions, the magnetic
forces developed force
the jaws together,
gripping the bus bar
more firmly. Heavy-duty
jaw connectors are
plated to ensure good
conductivity at the
contact.

 

[Sierrasparky]

I was told that higher fault-current rating of the equipment will dictate how the equipment is constructed. So the higher the fault-current rated equipment will have more support for the bussing and bolt-in style breakers.

Although the I-line equipment is plug-on, it has this feature design:


Breaker connections
are ?blow-on? type.
Under high-level fault
conditions, the magnetic
forces developed force
the jaws together,
gripping the bus bar
more firmly. Heavy-duty
jaw connectors are
plated to ensure good
conductivity at the
contact.

Interesting!

 

[jim dungar]

I was told that higher fault-current rating of the equipment will dictate how the equipment is constructed. So the higher the fault-current rated equipment will have more support for the bussing and bolt-in style breakers.

240V plug-on breakers are available up to 65kAIC.

There is no reason there must be a difference between the bussing for some style plug-on and bolt-on breakers. Sticking with the Square D brand, their 277V EH (plug-on) and EHB(bolt-on) were used with the same bus bars.

 

[templdl]

Interesting!

Ditto, I wonder where this thought originated from? Did it come frpm the manufacturer. Which working for 2 major electrical manufacturers for 18 year I would have thought that would have been part of the selling points. But there were none. Why are there 'bolted pressure switches' rather than basic fusible disconnect switches?

 

[jim dungar]

Ditto, I wonder where this thought originated from? Did it come frpm the manufacturer. Which working for 2 major electrical manufacturers for 18 year I would have thought that would have been part of the selling points. But there were none. Why are there 'bolted pressure switches' rather than basic fusible disconnect switches?

The information comes from the manufacturer, it is part of their normal marketing literature.

http://static.schneider-electric.us...ay/I-Line and I-Line II Busway/0600DB1004.pdf

 

[templdl]

The information comes from the manufacturer, it is part of their normal marketing literature.

http://static.schneider-electric.us...ay/I-Line and I-Line II Busway/0600DB1004.pdf

Thanks, I'll take a look at it.