Danfoss VLT AutomationDrive FC 301 Programming Manual page 52

Parameter Descriptions
Resistance (Rr)) for asynchronous motors, depending on
winding temperature. The calculation is:
Rs = Rs 20° C x (1 + α cu x Δ T ) Ω
KTY sensors can be used for motor protecting (1-97 KTY
Threshold level).
3 3
FC 302 can handle 3 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.
4500
4000
3500
3000
2500
2000
1500
1000
500
0
-25
Illustration 3.15 KTY Type Selection
KTY Sensor 1: 1 kΩ at 100 °C (e.g. Philips KTY 84-1)
KTY Sensor 2: 1 kΩ at 25 °C (e.g. Philips KTY 83-1)
KTY Sensor 3: 2 kΩ at 25 °C (e.g. Infineon KTY-10
NOTICE
If the temperature of the motor is utilised through a
thermistor or KTY sensor, the PELV is not complied with
in case of short circuits between motor windings and
sensor. To comply with PELV the sensor must be extra
isolated.
3.3.11.3 ETR
The calculations estimate the need for a lower load at
lower speed due to less cooling from the fan incorporated
in the motor.
50
VLT
where
α cu = 0.00393
0 25 50 75 100
Temperature [°C]
KTY type 1 KTY type 2
®
AutomationDrive FC 301/302 Programming Guide
t [s]
2000
1000
600
500
400
300
200
100
60
50
40
30
20
10
Illustration 3.16 ETR Profile
3.3.11.4 ATEX ETR
The B-option MCB 112 PTC Thermistor option offers ATEX
approved monitoring of motor temperature. Alternatively,
an external ATEX approved PTC protection device can be
used.
NOTICE
125 150
Only ATEX Ex-e approved motors may be used for this
KTY type 3
function. See motor nameplate, approval certificate, data
sheet or contact motor supplier.
When controlling an Ex-e motor with "Increased Safety", it
is important to ensure certain limitations. The parameters
that must be programmed are presented in the following
application example.
MG33MH02 - Rev. 2013-09-30
1.6 1.8 2.0
1.0 1.2 1.4
f OUT = 1 x f M,N (par. 1-23)
f OUT = 2 x f M,N
f OUT = 0. 2 x f M,N
I
M
I (par. 1-24)
MN