Danfoss VLT AutomationDrive FC 302 Programming Manual page 56

Parameter Descriptions
1-90 Motor Thermal Protection
Option:
[7] ETR
warning 3
[8] ETR trip 3
3 3
[9] ETR
warning 4
[10] ETR trip 4
[20] ATEX ETR
[21] Advanced
ETR
NOTICE
If [20] ATEX ETR is selected, follow the instructions in the
dedicated chapter of the VLT
Guide and the instructions provided by the motor
manufacturer.
NOTICE
If [20] ATEX ETR is selected, parameter 4-18 Current Limit
must be set to 150%.
3.3.13.1 PTC Thermistor Connection
R
(Ω)
4000
3000
1330
550
250
-20°C
Illustration 3.12 PTC Profile
Using a digital input and 10 V as power supply:
Example: The frequency converter trips when the motor
temperature is too high.
Parameter set-up:
54
VLT
Function:
Activates the thermal monitoring function for
Ex-e motors for ATEX. Enables
parameter 1-94 ATEX ETR cur.lim. speed
reduction, parameter 1-98 ATEX ETR interpol.
points freq. and parameter 1-99 ATEX ETR
interpol points current.
®
AutomationDrive Design
 nominel -5°C
 nominel +5°C
 nominel
Danfoss A/S © Rev. 10/2014 All rights reserved.
®
AutomationDrive FC 301/302
Set parameter 1-90 Motor Thermal Protection to [2]
Thermistor Trip
Set parameter 1-93 Thermistor Source to [6] Digital Input
39 42 50 53 54
12 13 18 19
PTC / Thermistor
Illustration 3.13 PTC Thermistor Connection - Digital Input
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 parameter 1-90 Motor Thermal Protection to [2]
Thermistor Trip
Set parameter 1-93 Thermistor Source to [2] Analog Input 54
39 42 50 53 54
PTC / Thermistor
Illustration 3.14 PTC Thermistor Connection - Analog Input
Input
digital/analog
Digital
Analog
NOTICE
Check that the selected supply voltage follows the
specification of the used thermistor element.
3.3.13.2 KTY Sensor Connection
 [°C]
(FC 302 only)
KTY sensors are used especially in permanent magnet
servo motors (PM motors) for dynamic adjusting of motor
parameters as stator resistance (parameter 1-30 Stator
Resistance (Rs)) for PM motors and also rotor resistance
(parameter 1-31 Rotor Resistance (Rr)) for asynchronous
motors, depending on winding temperature. The
calculation is:
55
OFF
27 29 32 33 20 37
ON
<800 Ω
55
OFF
ON
<3.0 k Ω
>3.0 k
Supply voltage Threshold
cut-out values
< 800 Ω - > 2.7 kΩ
10 V
10 V < 3.0 kΩ - > 3.0 kΩ
R
>2.7 kΩ
R
Ω
MG33MJ02