Product Manual

overloaded due to additional weight of product added to the conveyor,
the controller should notice a change in pulses from the encoder, for the
speed of the conveyor slows down from this additional weight, and the
controller will send a signal to the motor to speed up to compensate
for this load change. Once the load has been returned to the standard
expected load, the control will again see a signal from the encoder and
will slow the motor down to the needed speed.
There are two main types of Encoders, Rotary and Linear and each type
can use different sensing technologies. They include Optical, Magnetic
or Inductive. Optical Rotary encoders are the most common type used.
Thermal Protection (Overload)
A thermal protector, automatic or manual, mounted in the end frame
or on a winding, is designed to prevent a motor from getting too
hot, causing possible fire or damage to the motor. Protectors are
generally current- and temperature-sensitive. Some motors have no
inherent protector, but they should have protection provided in the
overall system’s design for safety. Never bypass a protector because of
nuisance tripping. This is generally an indication of some other problem,
such as overloading or lack of proper ventilation.
Never replace nor choose an automatic-reset thermal overload
protected motor for an application where the driven load could cause
personal injury if the motor should restart unexpectedly. Only manual-
reset thermal overloads should be used in such applications.
Basic types of overload protectors include:
Automatic Reset: After the motor cools, this line-interrupting
protector automatically restores power. It should not be used where
unexpected restarting would be hazardous.
Manual Reset: This line-interrupting protector has an external button
that must be pushed to restore power to the motor. Use where
unexpected restarting would be hazardous, as on saws, conveyors,
compressors and other machinery.
Resistance Temperature Detectors: Precision-calibrated resistors
are mounted in the motor and are used in conjunction with an
instrument supplied by the customer to detect high temperatures.
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