Klixon motor protection for
aircraft prevents hazards beyond the control of
the manufacturer — hazards such as sustained overload and excessive temperatures. Since
the protecting devices are sensitive to both temperature and current they inherently
protect against a variety of abnormal conditions while allowing maximum motor output
before shutdown. Motor life is extended by limiting the damaging temperatures to a
designed level.
The ACMP is basically a bimetallic thermostat with a built–in heating element which is installed
in series with the motor winding. The actuating element is a Klixon
snap–acting thermal disc. The built–in heaters simulate winding temperatures caused by
increases in current. This protector provides crisp, positive switching when the specified
trip current is sustained for a specific duration at room temperature. The device will also
actuate when an excessive ambient temperature condition occurs, providing protection against overheat
conditions other than overload. Separately, the disc protects against excessive ambient
temperature and the heaters protect against excessive current increases (as experienced during
locked motor conditions). Together, the heaters and disc protect against any combination of
overload and ambient conditions.
PERFORMANCE Maximum Current Ratings
Standard ratings are available in approximately 5% current steps at ultimate trip for motors with maximum
allowable temperatures of 120°C, 150°C, 175°C, and 200°C.
|
28 VDC |
120 VAC |
SKA |
16 amps |
16 amps |
MKA |
50 amps |
50 amps |
KA |
100 amps |
100 amps |
SJE |
30 amps |
30 amps |
MJE |
60 amps |
60 amps |
BJE |
120 amps |
120 amps |
Ratings are for device series. Specific devices may vary.
APPLICATION
Inherent protection means that a protector is built into a motor and becomes an
integral part of the system. For this reason, Klixon protectors should only be
applied by the motor manufacturer after detailed application tests to determine the
heating characteristics of the motor under a full range of load and ambient conditions
to verify the selected rating will meet the specific application requirements. Consult a
sales correspondent at left for test samples.
