Cooling And Airflow - Danfoss FC 300 Design Manual

7 Mechanical Installation - Frame size D, E and
F

7.2.6 Cooling and Airflow

Cooling
Cooling can be obtained in different ways, by using the cooling ducts in the bottom and the top of the unit, by taking air in and out the back of the unit
or by combining the cooling possibilities.
Duct cooling
A dedicated option has been developed to optimize installation of IP00/chassis frequency converters in Rittal TS8 enclosures utilizing the fan of the
frequency converter for forced air cooling of the backchannel. The air out the top of the enclosure could but ducted outside a facility so the heat loses
from the backchannel are not dissipated within the control room reducing air-conditioning requirements of the facility.
Installation of Duct Cooling Kit in Rittal enclosures
Please see
Back cooling
The backchannel air can also be ventilated in and out the back of a Rittal TS8 enclosure. This offers a solution where the backchannel could take air from
outside the facility and return the heat loses outside the facility thus reducing air-conditioning requirements.
NB!
A doorfan(s) is required on the enclosure to remove the heat losses not contained in the backchannel of the drive and any additional
losses generated from other components installed inside the enclosure. The total required air flow must be calculated so that the
appropriate fans can be selected. Some enclosure manufacturers offer software for performing the calculations (i.e. Rittal Therm
software). If the VLT is the only heat generating component in the enclosure, the minimum airflow required at an ambient temperature
7
of 45 o C for the D3 and D4 drives is 391 m
drive is 782 m
Airflow
The necessary airflow over the heat sink must be secured. The flow rate is shown below.
Enclosure protection
IP21 / NEMA 1
IP54 / NEMA 12
IP21 / NEMA 1
IP54 / NEMA 12
IP00 / Chassis
* Airflow per fan. Frame size F contain multiple fans.
Table 7.3: Heatsink Air Flow
NB!
The fan runs for the following reasons:
1.
2.
3.
4.
5.
6.
Once the fan is started it will run for minimum 10 minutes.
External ducts
If additional duct work is added externally to the Rittal cabinet the pressure drop in the ducting must be calculated. Use the charts below to derate the
frequency converter according to the pressure drop.
142
, for further information.
3 /h (230 cfm). The minimum airflow required at an ambient temperature of 45
3 /h (460 cfm).
Frame size
D1 and D2
E1 P250T5, P355T7, P400T7
E1 P315-P400T5, P500-P560T7
F1, F2, F3 and F4
F1, F2, F3 and F4
D3 and D4
E2 P250T5, P355T7, P400T7
E2 P315-P400T5, P500-P560T7
AMA
DC Hold
Pre-Mag
DC Brake
60% of nominal current is exceeded
Specific heatsink temperature exceeded (power size dependent).
MG.33.BC.02 - VLT
Door fan / Top fan airflow
3
170 m /h (100 cfm)
340 m 3 /h (200 cfm)
340 m 3 /h (200 cfm)
700 m 3 /h (412 cfm)*
525 m 3 /h (309 cfm)*
255 m 3 /h (150 cfm)
3
340 m /h (200 cfm)
3
340 m /h (200 cfm)
® is a registered Danfoss trademark
FC 300 Design Guide
o C for the E2
Airflow over heatsink
3
765 m /h (450 cfm)
1105 m 3 /h (650 cfm)
1445 m 3 /h (850 cfm)
985 m 3 /h (580 cfm)
985 m 3 /h (580 cfm)
765 m 3 /h (450 cfm)
3
1105 m /h (650 cfm)
3
1445 m /h (850 cfm)