Danfoss VLT AutomationDrive FC 301 Programming Manual page 77

Parameter Descriptions
3.2.15 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 1.2 1.4 1.6 1.8
Illustration 3.16 ETR Profile
3.2.16 ATEX ETR
®
The VLT PTC Thermistor Card MCB 112 offers ATEX-
approved monitoring of motor temperature. Alternatively,
an external ATEX-approved PTC protection device can be
used.
NOTICE
Only use ATEX Ex-e-approved motors for this function.
See the motor nameplate, approval certificate, datasheet,
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 Table 3.9.
M0013101
Programming Guide
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)
2.0
MN
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Function
Parameter 1-90 Motor Thermal
Protection
Parameter 1-94 ATEX ETR cur.lim.
speed reduction
Parameter 1-98 ATEX ETR
interpol. points freq.
Parameter 1-99 ATEX ETR interpol
points current
Parameter 1-23 Motor Frequency
Parameter 4-19 Max Output
Frequency
Parameter 4-18 Current Limit
Parameter 5-15 Terminal 33
Digital Input
Parameter 5-19 Terminal 37 Safe
Stop
Parameter 14-01 Switching
Frequency
Parameter 14-26 Trip Delay at
Inverter Fault
Table 3.9 Parameters
NOTICE
Compare the minimum switching frequency requirement
stated by the motor manufacturer to the minimum
switching frequency of the frequency converter, the
default value in parameter 14-01 Switching Frequency. If
the frequency converter does not meet this requirement,
use a sine-wave filter.
More information about ATEX ETR thermal monitoring can
be found in Application Note for FC 300 ATEX ETR Thermal
Monitoring Function.
3.2.17 Klixon
The Klixon type thermal circuit breaker uses a KLIXON
metal dish. At a predetermined overload, the heat caused
by the current through the disc causes a trip.
Using a digital input and 24 V as supply:
Example: The frequency converter trips when the motor
temperature is too high.
Parameter set-up:
Setting
[20] ATEX ETR
20%
Motor nameplate.
Enter the same value as for
parameter 4-19 Max Output
Frequency.
Motor nameplate, possibly
reduced for long motor cables,
sine-wave filter, or reduced
supply voltage.
Forced to 150% by 1-90 Motor
Thermal Protection option [20]
[80] PTC Card 1
[4] PTC 1 Alarm
Check that the default value
fulfills the requirement from
the motor nameplate. If not,
use a sine-wave filter.
0
®
75
3 3