Warner Electric FB-375, FB475, FB650 User Manual

Electrically Released

Brakes FB-375, 475, 650

P-237
819-0289

Installation Instructions

Contents

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Installing the Brake . . . . . . . . . . . . . . . . . . . . . . . 4

Power Supplies and Electrical Connections. . . . . 6

Autogap Adjustment . . . . . . . . . . . . . . . . . . . . . . 6

Operating Instructions . . . . . . . . . . . . . . . . . . . . . 7

Illustration Drawings . . . . . . . . . . . . . . . . . . . . . 10

Motor Adapter Dimensions . . . . . . . . . . . . . . . . 11

Bushing Part Numbers . . . . . . . . . . . . . . . . . . . 13

Warranty . . . . . . . . . . . . . . . . . . . . . . . Back Page

Failure to follow these
instructions may result in product
damage, equipment damage, and
serious or fatal injury to personnel.

This service manual tells how to install, adjust,
and maintain your Warner Electric brake. It also
contains information for part replacements when
needed.

Warner Electrically-Released Brakes are high
performance, high torque units. To obtain the
required performance and life, the brake must
be installed exactly in accordance with the
instructions of this service manual. Failure to do so
can result in unit breakdown or destruction and
possible injury or damage to persons and property.
After carefully reading these instructions, no
assembly or installation difficulties should be
encountered.

The Warner Electric warranty does not apply to
any unit which is not installed, used, operated and
maintained in accordance with Warner Electric’s
instructions.

Warner Electric • 800-825-9050 P-237 • 819-0289

2

Introduction

Warner Electric Electrically Released Brakes function
on the same principle of “response to magnetic
attraction” that operates other Warner Electric
brakes and clutches. Braking torque in these brakes
depends on ceramic permanent magnets which
have a high resistance to demagnetization. With the

Autogap

Automatic wear adjust

®

power off, the unit produces full braking torque. The
brake is released by generating an electromagnetic
field which opposes the field produced by the
permanent magnets. An adjustable voltage or
current control should be used to achieve best
release.

Long Life – High Cycle Rates

Segmented armature provides high

heat dissipation and long service life.

Capable of rapid cycling.

High Torque

Powerful permanent magnets.

Electrically Released

Brake automatically

engages when power is

turned off– releases

when power is applied.

Mounting Flexibility

The FB torque arm feature permits

mounting on any shaft. Wide

range of shaft sizes.

Warner Electric • 800-825-9050 P-237 • 819-0289

3

Installation Instructions

Motor Shaft
Brake Key

Set
Screws (2)

Shaft

FB-375

Sheave Key Motor Shaft

Key

Motor
Shaft

Set
Screws (2)

Set
Screws (2)

FB-375

Adapter

Electrically

Released

Brake Key

Sizes FB-375 Through FB-650

Installing the Brake

Note: Failure to set autogap using the

procedures in this manual may cause
overheating and premature failure.

Step1:

The first installation step applies only to the
optional motor adapter (See Figure 1). For
installation on a double shaft extension motor or
through shaft, proceed to Step 2A for the FB-375
or Step 2B for the FB-475 or FB-650.

tapered bushing or straight bore. Install the belts or
chain. To assemble the brake on the motor adapter

proceed to Step 2A for the FB-375 or Step 2B for

the FB-475 or FB-650.

Step 2A:

Check to insure that all parts are clean and
free from burrs and chips. Insert the key in
the shaft extension keyway. Slide the brake
assembly into position on the shaft extension
(See Figure 1 or 2). Tighten the set screws.
Go to Step 3.

Step 2B:

Check to insure that all parts are clean and free
from burrs or chips. Insert the key into the shaft
keyway. Place the bushing into the hub and match
half holes to make complete holes. Each hole will
be threaded on one side only. Place the screws
loosely into the holes which are threaded on the
hub side. Slip the assembly onto the shaft and
locate it in the desired position (See Figure 3).

All parts must be clean and free from burrs or
chips before assembly. Insert the motor shaft key
in the motor shaft. Tighten the motor adapter set
screws. Insert the sheave or sprocket key into
the motor adapter keyway. Install the sheave or
sprocket on the motor adapter either with a

Figure 2

FB-375 without Motor Adapter

Tighten the screws alternately and evenly until all are

pulled up very lightly. Tap against the large end of
the bushing with a plastic hammer to avoid
damaging the bushing. The screws can then be
tightened again, using the following torque
specifications:

FB-475 55 in. lb.
FB-650 175 in. lb.

Repeat this alternate tapping and retightening until

Figure 1

FB-375 with Motor Adapter

Warner Electric • 800-825-9050 P-237 • 819-0289

4

the specified wrench torque no longer turns the
screws.

To disassemble, remove both screws and

FB-475 or FB-650

Bushing

Bushing
Screws

Bushing Key

Shaft

Counterclockwise Rotation

Clockwise Rotation

Rotation

Torque Arm May Be Mounted

in Any Direction

If Direction of
Belt Pull
Then Locate
Torque Arm Tab

Rotation

If Direction of

Belt Pull

Then Locate

Torque Arm Tab

If Direction of

Belt Pull

Then Locate

Torque Arm Tab

If Direction of
Belt Pull
Then Locate
Torque Arm Tab

Electrically Released Brake

Viewed From Armature Side

reinsert one screw in the vacant hole (threads
on bushing). Tighten this screw until the
bushing is loosened in the hub. If the bushing
does not loosen, tap on the hub. Go to Step 3.

Installing The Torque Arm

Step 3:

The maximum length threaded rod is furnished
for normal mounting. (Consult the factory for
recommendations on a longer arm.) The
threaded rod can be cut to any desired length.
One rod end must be secured to the tab on the
Electrically Released Brake and the other end
must be secured to a solid base. Although the
torque arm may be mounted in either direction,
the position of the tab and arm is important.
Recommended position relative to shaft rotation
is shown in Figure 4. On reversing applications
where the rod is in compression every other
cycle, the rod must be relatively short, or a
special heavier rod may be necessary.

Figure 3

Do not connect rigid conduit
directly to the conduit box. A minimum of 12”
of flexible liquid tight conduit or other suitable
flexible wiring with appropriate fittings is
required. Flexible wiring is required to prevent
side loading of bearing on bearing mounted
clutches and possible deformation or breakage
of the conduit box or clutch/brake components
during assembly.

Warner Electric • 800-825-9050 P-237 • 819-0289

Figure 4

5