3.2.6 Switching frequency and temperature
The drive inverter cooling is designed by way that the heat sink overtemperature thresh-
old is not exceeded at rated conditions. A switching frequency higher than the rated
switching frequency also produces higher losses and thus a higher heat sink heating.
If the heat sink temperature reaches a critical threshold (
T
DR
) the switching frequency
can be reduced automatically, in order to prevent that the drive inverter switches off
due to overheating of the heat sink. If the heat sink temperature falls below TUR, the
switching frequency is increased back to the setpoint. At temperature
T
EM
the switching
frequency is immediately reduced to rated switching frequency. "Derating“ must be acti-
vated, for this function to work.
Module
A
b
C
Rated switching frequency
1)
f
SN
/ kHz
8
Minimum switching frequency
1)
f
S_min
/ kHz
8
Maximum switching frequency
1)
f
S_max
/ kHz
16
Maximum heat sink temperature
T
HS
/ °C
75
80
Temperature for derating the switching frequency
T
DR
/ °C
65
70
Temperature for uprating the switching frequency
T
UR
/ °C
45
50
Temperature for switching to rated switching frequency
T
EM
/ °C
70
75
Maximum internal temperature
T
IT
/ °C
95
Table 17:
Switching frequency and temperature
1) The output frequency is to be limited in such a way that it does not exceed 1/10 of the switching frequency.
3.2.7 Cooling and coolant connection
Design system
Material
max. operating
pressure
Connection
Aluminium heat sink
EN-AW-6060 T66
2 bar
coolant for all housing sizes“
NOTICE
Deformation of the heat sink by pressure peaks!
Maximum test pressure 4 bar!
►
Maximum test pressure may not be exceeded briefly by pressure
peaks !
►
Observe Directive 2014/68/EU for pressure equipment !
44
SYSTEM AND MODULE DATA
Summary of Contents for COMBIVERT T6APD
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