Warner Electric PCBC-1525_1225 User Manual
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Warner Electric • 800-825-9050
P-214
•
819-0518
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.
Coil Data
Unit Size
PB & PC-825
PB & PC-1000
PB & PC-1225
PB & PC-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
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 mate-
rial 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 slip-
ping the friction surfaces together at reduced volt-
age. 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 40% of the rated value.
The unit should be cycled on and off to allow suffi-
cient time between slip cycles to prevent overheat-
ing.
When a Warner Electric brake or clutch is properly
assembled and installed, no further servicing, lubri-
cation, 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 rema-
chine 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 .002"
- .004" below the metal poles.