Danfoss FC 300 Design Manual page 171

FC 300 Design Guide
Using an analog input and 10 V as power supply:
Example: The frequency converter trips when
the motor temperature is too high.
Parameter set-up:
Set Par. 1-90 Motor Thermal Protection
to Thermistor Trip [2]
Set Par. 1-93 Thermistor Source to
Analog Input 54 [2]
Do not select a reference source.
Input Supply
Digital/ana- Voltage
log Volt
Digital 24 V
Digital 10 V
Analog 10 V
NOTE
Check that the chosen supply voltage
follows the specification of the used
thermistor element.
Select ETR Warning 1-4, to activate a warning on
the display when the motor is overloaded.
Select ETR Trip 1-4 to trip the frequency converter
when the motor is overloaded.
Programme a warning signal via one of the
digital outputs. The signal appears in the event
* default setting ( ) display text
How to Program
Threshold
Cut-out Values
< 6.6 kΩ - > 10.8 kΩ
< 800Ω - > 2.7 kΩ
< 3.0 kΩ - > 3.0 kΩ
[ ] value for use in communication via serial communication port
MG.33.B6.22 - VLT is a registered Danfoss trademark
of a warning and if the frequency converter
trips (thermal warning).
ETR (Electronic Terminal Relay) functions 1-4 will
calculate the load when the set-up where they were
selected is active. For example ETR starts calculating
when setup 3 is selected. For the North American
market: The ETR functions provide class 20 motor
overload protection in accordance with NEC.
1-91 Motor External Fan
Option:
*
No
Yes
Function:
Select No [0] if no external fan is required, i.e.
the motor is derated at low speed.
Select Yes [1] to apply an external motor fan
(external ventilation), so no derating of the motor is
required at low speed. The graph below is followed
if the motor current is lower than nominal motor
current (see par. 1-24). If the motor current
exceeds nominal current, the operation time still
decreases as if no fan were installed.
[0]
[1]
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