Danfoss VLT HVAC Drive FC 102 Programming Manual page 54

Parameter Descriptions
3.3.13.1 PTC Thermistor Connection
R
(Ω)
3 3
4000
3000
1330
550
250
-20 °C
Illustration 3.11 PTC Profile
Using a digital input and 10 V as supply:
Example: The frequency converter trips when the motor
temperature is too high.
Parameter set-up:
•
Set 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 27
PTC / Thermistor
Illustration 3.12 PTC Thermistor Connection - Digital Input
Using an analog input and 10 V as supply:
Example: The frequency converter trips when the motor
temperature is too high.
Parameter set-up:
•
Set 1-90 Motor Thermal Protection to [2] Thermistor
Trip.
•
Set parameter 1-93 Thermistor Source to [2] Analog
Input 54.
52
VLT
 nominal -5 °C  nominal +5 °C
 nominal
55
OFF
29 32 33 20 37
ON
<800 Ω
Danfoss A/S © 03/2015 All rights reserved.
®
HVAC Drive FC 102
39 42 50 53 54
PTC / Thermistor
Illustration 3.13 PTC Thermistor Connection - Analog Input
Input
digital/analog
Digital
Analog
Table 3.9 Threshold Cut Out Values
 [°C]
NOTICE
Check that the selected supply voltage follows the
specification of the used thermistor element.
3.3.13.2 ETR
The calculations estimate the need for a lower load at
lower speed due to less cooling from the fan incorporated
in the motor.
t [s]
2000
1000
600
500
400
300
200
100
60
50
40
30
20
10
1.0
R
>2.7 kΩ
Illustration 3.14 ETR Profile
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
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
1.2 1.4 1.6 1.8 2.0
R
Ω
I
M
I (par. 1-24)
MN
MG11CE02