WEG Drive Scan, Manual

Page: 66 / 74

8
DRIVE SPECIALIST
Table 8.3: Values of
I
R
,
I
S
e
I
T
in the AC power supply as a function of the imbalances of power supply phases – 60 Hz frequency
Voltage imbalance I Max RMS I Min RMS I Max Peak
I
R
I
S
I
T
0% 15A 15A 22A 15A 15A 15A
2% 19A 15A 29A 15A 19A 15A
3% 20A 15A 33A 16A 20A 15A
4% 22A 16A 36A 16A 22A 16A
2. Cooling:
The fans that cool the power part of the inverters are fundamental for the safe operation of the power semicon-
ductors and guarantee the expected service life of the internal parts of the inverters. Air flow is a fundamental
factor for proper cooling. When mounting inverters in panels with a high protection rating, input and output
filters may restrain the cooling air flow. Dust buildup in the air filters of such panels is a common cause of
temperature rise in inverters. A malfunction of the cooling system may lead to the indication of a fault in the
inverters due to overtemperature, namely:
F011 - Rectifier Overtemperature,
F051 - IGBTs U Overtemperature,
F054 - IGBTs V Overtemperature,
F057 - IGBTs W Overtemperature,
F153 - Internal air Overtemperature,
F183 - IGBTs ov Temperature
The fans used in the CFW11 inverters are of the “Dual Bal Bearing” type with 3-wire DC power supply, en-
abling speed measurement. The fan manufacturer specifies an expected service life in hours considering
environmental conditions, such as maximum temperature and air pollution degree (pollution degree 2 ac-
cording to EN50178 and UL508C with non-conductive pollution). In case the fan exceeds this number of
hours of operation, it may present a failure, especially a mechanical one. A very common cause is the degree
of air pollution in industrial applications exceeding the specification.
On the Diagnostic tab, you can see values specified for the fans as shown in Figure 8.7 :
Figure 8.7: Indications related to the health of fans
Cooling health indications are described below:
Total time: total time in hours that the fan had been running. Note that the inverter automatically turns
the fans on and off depending on the inverter internal temperature;
Daily time: average number of hours the fan had been running per day. This value is updated daily and
is used to estimate the fan replacement time;
Replacement estimate: is the estimated date, based on the number of hours determined by the man-
ufacturer, for the fan service life to end. This date is calculated and updated every day, subtracting the
number of hours of operation of the last 24 hours from the maximum number of hours of service life
specified by the manufacturer and projecting the number of days remaining considering the average
of daily hours of operation.
Note that the service life will be valid if the fan is used in environmental conditions within the limits
specified by the manufacturer. The fan model varies according to the CFW11 model and the service
life information of the monitored model comes from a database stored in WEGnology.
The Normal (green), Alert (yellow) and Critical (red) states are defined by the following criteria:
• Normal: 180 days (from the current date)
≤
Replacement date
• Alert: 90 days
≤
Replacement date < 180 days,
• Critical: Replacement date < 90 days
Low Voltage Devices | 8-5