Warner Electric PB-825, PB-1000, PB-1225, PB-1525 User Manual

Primary Brake Pin Drive Armature PB-825,

PB-1000, PB-1225, PB-1525 Motor Brake and

Spline Drive MB-825, MB-1000, MB-1225 Pin Drive

P-208
819-0367

Installation Instructions

Contents

Installation Instructions

PB-825, PB-1000, PB-1225, PB-1525 . . . . . .3

MB-825, MB-1000, MB-1225 Spline Drive . . . .6

MB-825, MB-1000, MB-1225 Pin Drive . . . . . .8

Coil Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Burnishing and Maintenance . . . . . . . . . . . . . . .10

Illustration Drawings

PB-825, PB-1000 . . . . . . . . . . . . . . . . . . . . .12

PB-1225, PB-1525 . . . . . . . . . . . . . . . . . . . .16

MB-825, MB-1000, MB-1225 Spline Drive . . .20

MB-825, MB-1000, MB-1225 Pin Drive . . . . .26

Bushing Part Numbers . . . . . . . . . . . . . . . . . . .32

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

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

Warner Electric • 800-825-9050 P-208 • 819-0367

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Primary Brake Normal Duty

Pilot

Diameter

Mounting Surface

Magnet

Pin Drive Armature
PB-825, PB-1000, PB-1225, PB-1525

A. Installing the Conduit Box

Install the conduit box on the magnet.
Instructions for this procedure can be found
with conduit box.

B. Mounting the Magnet

The brake magnet is mounted to a stationary
machine member by a flange. Extreme care
must be taken in selecting the location for the
mounting of the magnet. Proper positioning is
very important for the unit to function correctly.

1. A pilot diameter on the mounting surface
is essential to hold the magnet within the
required tolerances (see Figure 1).

3. Once the mounting surface has been prepared,
the magnet is bolted in place with capscrews and
lockwashers. (See Figure 2.)

Figure 2

4. After assembly, the magnet must be concentric
and square within the required tolerances listed
on the illustration drawing. (See Figure 3.)

Figure 3

C. Assembling the Armature and Hub

Assemble the armature to the armature hub with the

Figure 1

2. A machined pilot diameter is provided on the
magnet mounting flange (refer to illustration
drawings) to aid in the proper positioning of
the magnet.

Warner Electric • 800-825-9050 P-208 • 819-0367

autogap mounting accessory. Refer to Figure 4. The
hub is reversible. The side on which the armature is
mounted will depend on the direction in which the
taperlock bushing must enter.

The autogap assembly is a double spring device
which allows for automatic armature clearance and
adjustment for wear. The smaller or conical spring
pushes the armature from the magnet face, leaving a
gap of about 1/32-inch, while the straight spring
automatically follows up for wear. This combination
maintains maximum efficiency throughout the life of
the unit.

3

Armature

Set

Screw

Bushing

Hub

Light

Spring

Detent
Spring

Drive Pin

Retainer

Ring

Heavy

Spring

Retainer

Figure 4

The assembly procedure for the autogap
accessory is as follows:

Step 1

Place the straight springs (white) over the
armature bosses on the back side of the
armature (Figure 5).

Figure 5

Step 2

Compress the heavy (red) spring on each drive pin
by sliding the detent spring towards the head of
the pin (Figure 6).

Step 3

Insert the assembled drive pins through the
armature (entering from segmented side), through
the straight (white) springs, and into the armature

®

hub. Note: Apply Grade "AA" Loctite
on the pin threads (Figure 7).

Figure 7

Step 4

Tighten the pins until the shoulders of the
pins are against the face of the hub. Since the
threads are class No. 3 fit, the pins may seem
to bind.

Sealant

The straight springs must not
get caught under the shoulders of the
drive pins.

Step 5

Check to see that the armature is completely
compressed against the face of the hub.

Figure 6

Warner Electric • 800-825-9050 P-208 • 819-0367

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Step 6

Armature

1/32-Inch

Magnet

To set the autogap, slide the detent spring
retainers against the armature face. Note: This

position must not be disturbed during
completion of the assembly (Figure 8).

3. Place the face of the armature approximately

1/32-inch from the face of the magnet. Once
this gap is set, it will be automatically
maintained throughout the life of the unit.
(See Figure 9.)

Figure 8

D. Mounting the Armature Assembly

The armature and armature hub are mounted on
the shaft with a taperlock bushing. All parts must
be clean and free from burrs and chips before
assembling.

1. Place the bushing into the hub and insert the
key. The key is a side-to-side fit and should not
contact the top of the keyway.

2. Insert the locking setscrews into the bushing
and slide the assembly onto the shaft.

Figure 9

4. Securely fasten the armature assembly to the
shaft by alternately tightening each setscrew.
During the tightening process, the bushing
should be tapped lightly to make certain it
seats-in properly.

Warner Electric • 800-825-9050 P-208 • 819-0367

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Motor Brake Spline Drive Armature
MB-825, MB-1000, MB-1225

The motor brakes will mount on a NEMA "C" face
motors frame size 213C, 215C 254UC and
256UC.

A. Mounting the Splined Armature Hub

1. Insert the bushing into the splined armature
hub. Insert the two capscrews loosely into the
bushing.

2. Insert the key in the motor shaft.

3. Holding the hub so that the capscrew heads
are facing the NEMA motor, slide the hub on to
the motor shaft. (Figure 1)

B. Mounting the Adapter

1. Mount the adapter to the C-flange end bell of
the motor using capscrews and lockwashers.
The flat side of the O.D. of the adapter should
be mounted towards the bottom of the
motor. (Figure 2)

Figure 2

Figure 1

4. Position the armature hub in the location
specified by dimensions on the illustration
drawings.

5. Secure the hub in this position by alternately
tightening the two capscrews in the bushing.

6. After tightening the capscrews, recheck the
positioning dimension of the splined armature
hub. Reposition if necessary.

2. Mount the magnet to the adapter with
capscrews and lockwashers. Be sure both
surfaces are clean and free of burrs and
chips. Position the magnet so that the lead
wires are in position with the desired conduit
entrance. (Figure 3)

Figure 3

Warner Electric • 800-825-9050 P-208 • 819-0367

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C. Assembling the Armature and Hub

These units contain spline drive armatures.
The armatures are shipped with a built-in spring
accessory. This device automatically maintains
a gap of about 1/32-inch between the armature
and magnet faces for the life of the unit.

These units are shipped with the armature,
splined armature adapter, and autogap already
assembled.

1. Slide the spline drive armature onto the splined
hub. The segmented side of the armature faces
toward the magnet. (Figure 4)

3. Bolt the cover to the adapter using
capscrews and lockwashers. (Figure 5)

Figure 5

Figure 4

2. Press on the splined armature adapter, and
slide the armature forward until it is in full
contact with the magnet face. Note: The

autogap detent ring in the splined adapter
grips the hub very tightly, and requires
considerable force to slide onto the hub.
When the armature is released, it will spring
back about 1/32-inch. This gap will be
automatically maintained for the life of
the unit.

Warner Electric • 800-825-9050 P-208 • 819-0367

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Motor Brake

Hub Drive Pin

Red Spring

Detent Retainer

Detent Ring

1/2-inch

Light
Spring

Armature

Pin Drive Armature
MB-825, MB-1000, MB-1225

The motor brakes will mount on a NEMA "C"
face motors frame size 213C, 215C, 254UC
and 256UC.

A. Mounting the Adapter and Magnet

1. Mount the adapter to the C-flange end bell
of the motor. Secure the adapter with
capscrews and lockwashers.

2. Mount the magnet to the adapter with
capscrews and lockwashers. Be sure both
surfaces are clean and free of burrs and
chips. A machined pilot diameter on the O.D.
of the magnet mounting flange corresponds
with a pilot diameter on the adapter.

Step 2

Assemble the red spring over the drive pin. The
smaller diameter of the spring should be against
the hub (Figure 1).

Step 3

Place the detent retainer over the pin. The
cupped-out portion should be against the spring.
(See Figure 2.)

Figure 2

Step 4

B. Assembling the Armature and Hub

Assemble the armature to the armature hub
with the autogap mounting accessory.

Follow these instructions to assemble the
armature and hub:

Step 1

Insert the drive pin into the hub and tighten until
the shoulder of the pin is against the hub.
(See Figure 1.)

Place the detent ring on the pin and press it into
the recessed portion of the detent retainer (Figure

2).

Step 5

Slide the detent ring towards the hub to allow
about 1/2" between the ring and the head of the
pin (Figure 2).

Step 6

Slide the armature onto the pins. The face of the
armature should be towards the hub. (Figure 3)

8

Warner Electric • 800-825-9050 P-208 • 819-0367

Figure 1

Figure 3

Step 7

Retainer Ring

1/16-inch

Capscrew

Armature

Hub

Magnet

Detent Spring Retainer

Assemble the light spring over the pin. The
large diameter of the spring should be against the
armature.

Step 8

Compress the spring to allow the retainer ring to
be snapped into the groove at the head of the pin
(Figure 4).

C. Mounting the Armature-Hub Assembly

1. Insert the taperlock bushing into the bore of the
hub.

3. Position the assembly to allow a gap of
1/16-inch between the faces of the armature
and magnet (Figure 5)

4. Secure the assembly in this position by
alternately tightening the locking setscrews.
The bushing should be tapped lightly from
time-to-time to make sure it seats-in properly.

5. Set the autogap by pressing the armature into
contact with the friction face and then releasing
the armature. The armature should spring back
approximately 1/32-inch. Once this gap is set it
will be automatically maintained throughout the
life of the unit.

6. Bolt the cover to the adapter using
capscrews and lockwashers (Figure 6).

Figure 4

2. Loosely insert the locking setscrews and slide

Figure 6

the assembly onto the shaft.

Figure 5

Warner Electric • 800-825-9050 P-208 • 819-0367

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Coil Data

Unit Size PB & MB-825 PB & MB-1000 PB & MB-1225 PB & MB-1525

Voltage — DC 6 24 90 6 24 90 6 24 90 6 24 90

Resistance @ 20°C — Ohms 1.27 20.4 223.3 1.23 19.7 248.7 1.33 22.3 261.7 1.45 19.8 258.4

Current — Amperes 4.74 1.18 .4 4.87 1.22 .36 4.5 1.08 .34 4.13 1.21 .35

Watts 28 28 36 29 29 33 27 26 31 25 29 31

Coil Build-up — Milliseconds 170 170 170 205 220 235 300 320 350 470 490 512

Coil Decay — Milliseconds 70 75 80 70 75 80 190 190 190 200 170 140

Notes: Build-up time equals current to approximately* 90% of steady state value and flux to 90%.
Decay time equals current to approximately* 10% of steady state value and flux to 10%.
*Approximately because current leads or lags flux by a small amount.

Burnishing and Maintenance

Burnishing

Intimate metal to metal contact is essential
between the armature and the metal rings (poles) of
the magnet or rotor. Warner Electric clutches and
brakes leave the factory with the friction material
slightly undercut to assure good initial contact.

Normally, the desired wearing-in process occurs
naturally as the surfaces slip upon engagement.

The time for wear-in, which is necessary to
obtain the ultimate torque of the unit, will vary
depending on speed, load, or cycle duty.

If maximum torque is required immediately after
installation, the unit should be burnished by slipping
the friction surfaces together at reduced voltage. It is
recommended that the burnishings be done right on
the application, if at all possible.

Burnishing at high speed will result in a smoother
wear-in pattern and reduce the time for burnishing.
The voltage should be set at approximately 30% or
50% of the rated value.

The unit should be cycled on and off to allow
sufficient time between slip cycles to prevent
overheating.

When a Warner Electric brake or clutch is
properly assembled and installed, no further
servicing, lubrication, or maintenance should be
required throughout the life of the unit.

Maintenance

Wear Pattern: Wear grooves appear on the

armature and magnet surfaces. This is a normal
wear condition, and does not impair functioning
of the unit. Normally, the magnet and armature,
as a mating pair, will wear at the same rate. It is
the usual recommendation that both
components be replaced at the same time.

Remachining the face of a worn armature is not
recommended. If a replacement armature is to
be used with a used magnet, it is necessary to
remachine the worn magnet face. In refacing a
magnet: (1) machine only enough material to
clean up the complete face of the magnet; (2)
hold the face within .005" of parallel with the
mounting plate; and (3) undercut the molded
facing material .001" - .003" below the metal
poles.

Heat: Excessive heat and high operating
temperatures are causes of rapid wear. Units,
therefore, should be ventilated as efficiently as
possible, especially if the application requires
fast, repetitive cycle operation.

Warner Electric • 800-825-9050 P-208 • 819-0367

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Foreign Materials: If units are used on
machinery where fine, abrasive dust, chips or grit
are dispelled into the atmosphere, shielding of
the brake may be necessary if maximum life is to
be obtained.

Where units are used near gear boxes or
transmissions requiring frequent lubrication,
means should be provided to protect the friction
surfaces from oil and grease to prevent serious
loss of torque.

Oil and grease accidentally reaching the friction
surfaces may be removed by wiping with a rag
dampened with a suitable cleaner, which leaves
no residue. In performing this operation, do not
drench the friction material.

If the friction materials have been saturated with
oil or grease, no amount of cleaning will be
completely effective. Once such a unit has been
placed back in service, heat will cause the oil to
boil to the surface, resulting in further torque loss.

with one magnet lead, will normally indicate
approximately .40 amperes for the 90 volt
units, 1.0 ampere for the 24 volt, and 3.5
amperes for the 6 volt series. These readings
are with the power on and the potentiometer
control in the maximum position.

Ohmmeter checks should be made with the
power off and the circuit open (to be certain,
disconnect one lead to the magnet). Average
resistance for the 90 volt series is 220 ohms;
for the 24 volt, 20 ohms; and for the 6 volt
series, 1.5 ohms. A very high or infinite
resistance reading would indicate an open coil.

If the above checks indicate that the proper
voltage and current is being supplied to the
magnet, mechanical parts should be checked
to assure that they are in good operating
condition and properly installed.

Torque Loss: If a brake or clutch slips or loses
torque completely, the initial check should be the
input voltage to the magnet as follows:

90-Volt Series: Connect a DC voltmeter with a
range of 0-100 or more directly across the
magnet terminals. With the power on and the
potentiometer turned up, a normal reading is 90
volts, although 85 to 95 is satisfactory. The
reading should drop as the potentiometer
control is adjusted counterclockwise.

24-Volt Series: Use a DC voltmeter with a
range of 0-30 volts or more. A normal reading
is approximately 22-26 volts.

6-Volt Series: Use a DC voltmeter of
approximately 0-15 volt range. A normal
reading is from 5.5 to 6.5 volts.

The above checks normally are sufficient.
Further checks may be made as follows: a
low range ammeter, when connected in series

Warner Electric • 800-825-9050 P-208 • 819-0367

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