Vacon NX User Manual page 24

vacon • 22
All values with cosϕ = 0.83 and efficiency = 97%.
*) c = power loss into coolant; a = power loss into air; T = total power loss; power losses of input chokes not
included. All power losses obtained using max. supply voltage, I
Closed Loop control mode. All power losses are worst case losses.
If some other mains voltage is used, apply the formula P =
Cooled drive output power.
The enclosure class for all NX Liquid-Cooled frequency converters is IP00.
If the motor is continuously (besides start and stop ramps) run at frequencies below 5 Hz, pay attention to the
drive dimensioning for low frequencies, i.e. maximum I
recommended to check the rating with your distributor or Vacon.
Drive overrating may also be necessary if the process requires high starting torque.
Table 6. Internal brake chopper unit (BCU) ratings, braking voltage 840—1100 VDC
Loadability
Converter
Rated min
Type
resistance
1)
NX_325 6
1)
NX_385 6
1)
NX_416 6
1)
NX_460 6
1)
NX_502 6
NX_820 6
NX_920 6
NX_1030 6
NX_1180 6
NX_1300 6
NX_1500 6
NX_1700 6
NOTE! Braking power: P
NOTE! Braking DC current: I
1)
Only 6 pulse drives
The internal brake chopper can also be used in motor application where 2...4 x Ch7x drives are used for a
single motor, but in this case the DC connections of the power modules must be connected together. The
break choppers are working independently of each other and because of this the DC connections must be
connected together otherwise there can be unbalance between the power modules.
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: info@clrwtr.com
4
Internal brake chopper ratings, braking voltage 840-1100 Vdc
Braking capacity at 840 Vdc
Rated cont. brak-
ing power
[Ω] [kW]
2,8 252
2,8 252
2,8 252
2,8 252
2,8 252
2,8 252
2,8 252
2,8 252
2,8 252
2,8 252
2,8 252
2,8 252
= U ^2 / R
brake brake brake
= P
in_max brake_max
and switching frequency of 3.6 kHz and
th
x Un x In x cosϕ x eff% to calculate the NX Liquid
3
= 0.66*I or choose drive according to I
H th
Braking capacity at 1100 Vdc
BCU rated cont.
Rated cont. brak-
braking current,
ing power
I
br
[kW]
[A]
300 432
300 432
300 432
300 432
300 432
300 432
300 432
300 432
300 432
300 432
300 432
300 432
/ U
brake
TECHNICAL DATA
. It is
H
BCU rated cont.
Chassis
braking current,
I
br
[A]
392 Ch72
392 Ch72
392 Ch72
392 Ch72
392 Ch72
392 Ch74
392 Ch74
392 Ch74
392 Ch74
392 Ch74
392 Ch74
392 Ch74