PowerPact B-frame Clearances, UL Standard

For all types of PowerPact B-frame circuit breakers that use uninsulated power connections (for example, busbars, spreaders, or uninsulated compression lugs), the minimum clearance distance between the enclosure backplate (grounded metal) and uninsulated power connections is shown below.

When using uninsulated connectors be sure to maintain the proper clearance between live parts and the grounded metallic back pan or use the insulation screen.

Minimum Enclosure Dimensions
Standard (80%)	100% Rated
14.6 x 8.5 x 3.16 in. (371 x 216 x 80 mm)	18.13 x 8.63 x 4.13 in. (461 x 219 x 105 mm)

Minimum Clearance Dimensions to Enclosure or Any Grounded Metal
Operating voltage V < 690 Vac, 250 Vdc
For devices equipped with:	Clearance
	Between devices	Between device and sheet metal
		Painted sheet metal			Bare sheet metal
		A1	A2	B	A1	A2	B
No terminal accessories	0	30 mm (1.18 in.)	5 mm (0.19 in.)	0	40 mm (1.57 in.)	5 mm (0.19 in.)	5 mm (0.19 in.)
Interphase barriers	0	0	0	0	0	0	5 mm (0.19 in.)
Long terminal shields	0	0	0	0	0	0	5 mm (0.19 in.)

Minimum Clearances to Bare Busbars
Operating voltage V ≤ 690 Vac, 250 Vdc
Clearances to live bare busbars *
Spacing E ≤ 60 mm (2.36 in.)		Spacing E > 60 mm (2.36 in.)
D1	D2	D1	D2
200 mm (7.87 in.)	100 mm (3.94 in.)	120 mm (4.72 in.)	60 mm (2.36 in.)

Exposed Conductor Clearance

An insulating screen or long terminal shield is required if C < 12.7 mm (< 0.5 in.) if voltage is ≥ 300 Vac.