4-2 Optional Accessories
MN409
Winding Thermocouple
−
TIC
Purpose
To measure or monitor winding temperature.
Principle of Operation
The TIC uses a junction of two dis
−
similar metals to generate a voltage which varies with change in
junction temperature.
Customer Interconnect
Using same type of
TIC
wire, connect to leads supplied in separate conduit box. Leads are tagged.
Remarks
1.
Can provide either continuous temperature measuring or temperature monitoring.
2.
Can measure temperature by using a potentiometer and converting from voltage to temperature by
using proper conversion tables.
3.
Needs separately mounted control and power source to read temperature or to provide a means of
relay operation for either alarm or motor shutdown features.
Winding Thermistors
Purpose
To indicate the winding temperature has exceeded normal operating temperatures.
Principle of Operation
Device is a semiconductor that changes its resistance abruptly at a certain temperature. The change is
used to trigger a switching action in an external control which provides an alarm or shutdown signal.
Customer Interconnect
Thermistor leads are brought to a terminal strip located on the coil head. Separate leads continue to
controller, located in the accessory conduit box, where customer connections are made.
Remarks
Cannot be used to measure or monitor winding temperatures. Similar to thermostat providing a switching
action to alarm or shutdown. Will not provide locked rotor protection.
Bearing Resistant Temperature Detector
−
RTD
Purpose
To measure or monitor bearing temperature during operation.
Principle of Operation
The RTD uses a wire wound in a coil. It is wound so that it is a non
−
inductive device. Its mode of
operation is that of a linear change in resistance with temperature.
Customer Interconnect
A terminal strip is supplied inside a conduit box. Leads are tagged.
Remarks
1.
Can provide either continuous temperature measuring or temperature monitoring.
2.
Needs a separately mounted control and power source to read temperatures or to provide a means
or relay operation for either alarm or motor shut down features.
3.
Temperature can be monitored using an ohm meter or a resistance bridge and converting the
resistance (after subtracting led resistance) to temperature by using the appropriate conversion
tables for the element.
This Manual:http://www.manuallib.com/baldor/mn409-large-ac-motors-handbook.html
