Technical data

March 2009
CA08102001E For more information visit: www.eaton.com
33-235
NEMA Contactors & Starters
33
Shoe Brakes — AC and DC Magnetic
511 Series
Contents
Description Page
AC and DC Magnetic Shoe Brakes
Product Description . . . . . 33-235
Application Description . . . 33-235
Features . . . . . . . . . . . . . . . 33-235
Brake Selection . . . . . . . . . 33-235
Shipping Weights. . . . . . . . 33-235
Product Selection. . . . . . . . 33-236
Dimensions . . . . . . . . . . . . 33-238
Size S-7 Brake and Wheel
Product Description
Cutler-Hammer
®
Type S Brakes from
Eaton’s electrical business are electri-
cally released and spring applied
providing “fail-safe” operation. The
retarding torque developed is directly
proportional to the spring pressure.
Application Description
■ Conveyors
■ Machine tools
■ Printing presses
■ Small cranes
■ Overhead doors
■ Dumb waiters
■ Vacuum molding machines
■ Carnival rides
Features
The brake wheel is of relatively large
size in relation to the torque developed
by the brake. This permits use of a
larger brake shoe lining and lower
shoe pressures. Low shoe pressure,
equally distributed over a large lining
area, results in even wear of the fric-
tion surfaces and even braking torque.
The oversize wheel type construction
also permits use of a smaller operating
solenoid that requires less current for
a given torque rating.
DC Brakes
Standard DC brakes are equipped with
shunt coils. The magnet coil circuit on
DC brakes consists of two separate
windings and a protective switch.
Mounting
Type S brakes are designed and
recommended for use and mounting
only in the horizontal position. Side
or vertical mountings are not recom-
mended because the solenoid loading
is altered, resulting in accelerated
wear and premature coil failure.
Brake Selection
The method most generally used to
determine required braking torque is
to calculate the full load motor torque
by the following formula:
The torque rating of the brake selected
should be at least equal to the full load
motor torque for the duty considered.
Figure 33-89. Standard Brake Wheels —
Approximate Dimensions
Table 33-350. Standard Brake Wheel Dimensions

Hub lengths other than standard are not available.
Shipping Weights
Table 33-351. Approximate Shipping Weights
T=5252 x hp
rpm
T=Full load motor torque in lb-ft
hp = Motor horsepower
rpm = Speed of shaft on which
brake wheel is mounted
W
Z
X
A
Y
Approximate Dimensions in Inches (mm) Bore
AZW

XYMax. Min.
4.00 (101.6)
5.50 (139.7)
7.00 (177.8)
2.75 (69.9)
3.25 (82.6)
4.25 (108.0)
1.63 (41.4)
2.00 (50.8)
3.00 (76.2)
1.38 (35.1)
1.63 (41.4)
1.25 (31.8)
2.50 (63.5)
3.25 (82.6)
4.00 (101.6)
1.38 (35.1)
2.00 (50.8)
2.25 (57.2)
.50 (12.7)
.75 (19.1)
1.00 (25.4)
Brake Size Torque Rating
ft-lb
Weight in Lbs. (kg)
Net —
Brake with Wheel
Net —
Wheel Only
Boxed —
Brake with Wheel
Type “S” AC Shoe Brakes
S-4
S-4
S-4
S-5-1/2
S-5-1/2
S-7
S-7
3
10
15
25
35
50
75
15.8 (7.2)
15.8 (7.2)
15.8 (7.2)
33.2 (15.1)
33.2 (15.1)
52.1 (23.7)
52.1 (23.7)
3.4 (1.5)
3.4 (1.5)
3.4 (1.5)
7.5 (3.4)
7.5 (3.4)
18.8 (8.5)
18.8 (8.5)
17.0 (7.7)
17.0 (7.7)
17.0 (7.7)
36.0 (16.3)
36.0 (16.3)
55.0 (25.0)
55.0 (25.0)
Type “S” DC Shoe Brakes
S-4
S-4
S-4
S-5-1/2
S-5-1/2
S-7
S-7
S-7
S-7
3
10
15
25
35
50
75
85
110
18.0 (8.2)
18.0 (8.2)
18.0 (8.2)
35.0 (15.9)
35.0 (15.9)
54.0 (24.5)
54.0 (24.5)
54.0 (24.5)
54.0 (24.5)
3.4 (1.5)
3.4 (1.5)
3.4 (1.5)
7.5 (3.4)
7.5 (3.4)
18.8 (8.5)
18.8 (8.5)
18.8 (8.5)
18.8 (8.5)
20.0 (9.1)
20.0 (9.1)
20.0 (9.1)
38.0 (17.3)
38.0 (17.3)
58.0 (26.3)
58.0 (26.3)
58.0 (26.3)
58.0 (26.3)