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7.2.7 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 instal-
lation 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.
Please see
Installation of Duct Cooling Kit in Rittal enclosures
,
for further information.
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.
NOTE
A door fan(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 of
45
°
C for the D3 and D4 drives is 391 m
3
/h (230 cfm). The
minimum airflow required at an ambient temperature of
45
°
C for the E2 drive is 782 m
3
/h (460 cfm).
Airflow
The necessary airflow over the heat sink must be secured.
The flow rate is shown below.
Enclosure protection
Frame size
Door fan(s) / Top fan airflow
Heatsink fan(s)
IP21 / NEMA 1
IP54 / NEMA 12
D1 and D2
170 m
3
/h (100 cfm)
765 m
3
/h (450 cfm)
E1 P250T5, P355T7, P400T7
340 m
3
/h (200 cfm)
1105 m
3
/h (650 cfm)
E1P315-P400T5, P500-P560T7
340 m
3
/h (200 cfm)
1445 m
3
/h (850 cfm)
IP21 / NEMA 1
F1, F2, F3 and F4
700 m
3
/h (412 cfm)*
985 m
3
/h (580 cfm)*
IP54 / NEMA 12
F1, F2, F3 and F4
525 m
3
/h (309 cfm)*
985 m
3
/h (580 cfm)*
IP00 / Chassis
D3 and D4
255 m
3
/h (150 cfm)
765 m
3
/h (450 cfm)
E2 P250T5, P355T7, P400T7
255 m
3
/h (150 cfm)
1105 m
3
/h (650 cfm)
E2 P315-P400T5, P500-P560T7
255 m
3
/h (150 cfm)
1445 m
3
/h (850 cfm)
* Airflow per fan. Frame size F contain multiple fans.
Table 7.3 Heatsink Air Flow
NOTE
The fan runs for the following reasons:
1.
AMA
2.
DC Hold
3.
Pre-Mag
4.
DC Brake
5.
60% of nominal current is exceeded
6.
Specific heatsink temperature exceeded (power
size dependent).
7.
Specific Power Card ambient temperature
exceeded (power size dependent)
8.
Specific Control Card ambient temperature
exceeded
Once the fan is started it will run for minimum 10 minutes.
Mechanical Installation - ...
FC 300 Design Guide
MG.33.BD.02 - VLT
®
is a registered Danfoss trademark
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