NOTE!
If [20] is selected,
4-18 Current Limit
must be set to 150%.
3.3.10.1 PTC Thermistor Connection
Figure 3.4 PTC profile
Using a digital input and 10 V as power supply:
Example: The Adjustable frequency drive trips when the
motor temperature is too high.
Parameter set-up:
Set
1-90 Motor Thermal Protection
to
Thermistor Trip
[2]
Set
1-93 Thermistor Source
to
Digital Input
[6]
PTC / Thermistor
R
OFF
ON
<800 Ω
+10V
130BA152.10
>2.7 kΩ
12 13
18
37
32
27
19
29
33 20
55
50
39 42
53 54
Using an analog input and 10 V as power supply:
Example: The Adjustable frequency drive trips when the
motor temperature is too high.
Parameter set-up:
Set
1-90 Motor Thermal Protection
to
Thermistor Trip
[2]
Set
1-93 Thermistor Source
to
Analog Input 54
[2]
Input
Digital/analog
Supply Voltage
Threshold
Cut-out Values
Digital
10 V
< 800
Ω
- > 2.7 k
Ω
Analog
10 V
< 3.0 k
Ω
- > 3.0 k
Ω
NOTE!
Ensure that the chosen supply voltage follows the specifi-
cation of the thermistor element utilized.
3.3.10.2 KTY Sensor Connection
(FC 302 only)
KTY sensors are used especially in permanent magnet
servo motors (PM motors) for dynamic adjusting of motor
parameters as stator resistance (
1-30 Stator Resistance (Rs)
)
for PM motors and also rotor resistance (
1-31 Rotor
Resistance (Rr)
) for asynchronous motors, depending on
winding temperature. The calculation is:
Rs = Rs20° C x (1 + αcu x ΔT) Ω
where
αcu = 0.00393
KTY sensors can be used for motor protecting (
1-97 KTY
Threshold level
).
FC 302 can handle three types of KTY sensors, defined in
1-95 KTY Sensor Type
. The actual sensor temperature can be
read out from
16-19 KTY sensor temperature
.
Parameter Descriptions
FC 300 Programming Guide
MG33MD22 - VLT
®
is a registered Danfoss trademark
3-25
3
3
Remote Site Products - 1-888-532-2706 - www.remotesiteproducts.com
http://www.remotesiteproducts.com/p-20872-Danfoss-131H4490-VLT-Automation-VT-Drive-VFD-FC302-460V-25-HP.aspx
