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CBC-300 & CBC-300-1 Series
Dual Channel Adjust Clutch/Brake Controls
Installation & Operating Instructions
P-2105-WE
819-0549
An Altra Industrial Motion Company
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Contents
Introduction .................................2
Specifications ...............................3
Mounting ...................................4
Electrical Connections .....................5, 6, 7
Internal Adjustments ..........................8
Troubleshooting Checklist ......................9
Warranty ...........................Back Page
Failure to follow these instructions
may result in product damage, equipment damage,
and serious or fatal injury to personnel.
Introduction
Warner Electric’s CBC-300 and CBC-300-1 are constant
current, solid state electronic power supplies designed
to operate any of the Warner Electric 90 Volt clutches
and brakes, including fail safe designs. They can operate
a single clutch or brake, two clutches, two brakes,
a combination clutch and brake, or a combination
clutch and fail safe brake, depending on the switching
arrangement used and the application requirements.
The CBC-300 series controls operate from 120 VAC
single-phase input power. They provide constant current
output as set by the torque adjustment potentiometers
on the front panel or remote potentiometer. On the CBC300 series both outputs are adjustable. Output current
ranges are selectable for the adjustable output channels
in one of five ranges by the DIP switches located on the
control’s printed circuit board.
Two versions of the CBC-300 are provided to handle
a wide range of applications. The standard version
is offered the same as before. The CBC-300-1
version is available where an external limit adjustment
potentiometers are required.
Operations of both units are identical except for the
method of the control potentiometer mounting. The
CBC-300-1, external potentiometer option, has terminal
blocks mounted on the PC boards for connection of the
potentiometers.
The potentiometers used can be supplied either as
optional accessory items or be obtained from a local
electronic supply house.
An internal 1.5A FA fuse is provided for line to ground
shorts.
Two LED indicators are provided on the front panel of
the control for “POWER” and “SHORT” indications.
The green indicator marked “POWER” is illuminated
whenever the AC input power is applied to the control. A
red indicator marked “SHORT” is illuminated whenever
a short circuit condition occurs in either of the outputs.
To reset, power must be removed, the shorted condition
cleared, and the AC input power reapplied to the control.
The enclosed version may be used with or without the
cover. Removal of the plastic cover when the control
is used in an enclosure will increase the operating
temperature range of the control.
2 Warner Electric • 800-825-9050 P-2105-WE 819-0549 5/17
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Specications
Input Power: 120 VAC, +10%, -15%, 50/60 Hz, single
phase, 215 VA maximum.
Current Ranges:
Switch Setting 1 2 3 4 5
Max Output, ma 60 175 245 305 533
Output: Pulse-width modulated full wave rectified DC.
Constant current, switch selectable ranges designed
for 90 volt DC clutches and brakes.
Ambient Temperature: -32°F to + 113°F (0°C to + 45°C)
with plastic cover installed. -32°F to +150°F (0°C
to + 66°C) with plastic cover removed, or board
assembly only.
Circuit Protection: Internal short circuit protection
on outputs. An internal fuse is provided for AC
ground faults. It is rated at 1.5A FA replaceable
(5mm X 20mm).
Control Adjust: CBC-300 via front panel potentiometer for
current adjustment.
CBC-300-1 via external mounted potentiometer for
current adjustment.
Status Indicators: “POWER” – green LED indicating AC
power is applied to the control.
“SHORT” – red LED indicating that a short
circuit condition exists on one or both of
the outputs.
Internal Adjustments: Current Range Selection via
DIP switches, SW1 for Channel 1 and SW2 for
Channel2.
External Switching: Mechanical or Electro-mechanical
Switching: Customer supplied, 1 amp, 125 V
minimum rating.
Solid-state NPN isolated transistor
Customer supplied, 2 amp, 250V minimum
rating. Maximum off state leakage current < 1 ma.
External Pots:
Remote current adjust pot
Customer supplied: 10,000 ohm, 2 watt, linear,
maximum distance from control to
potentiometer not to exceed 10 feet.
Optional Accessory Pot Kit;
part number, 6011-101-002
Wiring Entrance: Two 7/8” diameter entrance holes
located on the bottom of the control chassis on
enclosed units. No conduit entrances are on chassis
mount versions.
Enclosure: Rated NEMA 1 only – Control must be kept
clear of foreign materials, dust, grease and oil which
might affect its operation.
Part Numbers:
Enclosed Versions
CBC-300 6021-448-009
CBC-300-1 6021-448-002
Warner Electric • 800-825-9050 P-2105-WE 819-0549 5/17 3