De-Rating; De-Rating Information - Johnson Controls VFD66 Drive User Manual

5

De-rating

5.1

De-rating information

Figure 5-1 200/230 Vac Temperature De-Rating
12
10
8
6
4
2
0
40°C
104 F °
No de-rating for 400/460 Vac drives up to 60°C (140°F). Contact JCI application
engineering for 6KHz and 12KHz versions
This is the de-rating with the switching frequency at 3kHz.
NOTE
De-Rating examples
For these examples, the drive used is a VFD66EBA type. See Figure 5-1 and Table 5-1.
• If the VFD66EBA drive is used in Denver, Colorado (altitude 5200 ft), the output
rating is reduced (see Table 5-1). When the temperature is less than 122°F (50°C),
the VFD66EBA drive is rated for 9.96 amperes, as shown by the equation:
De-Rated maximum output amperes = 10.6 A x 0.94 = 9.96 amperes
• If the VFD66EBA drive is used in Denver, Colorado (altitude 5200 ft) and the
ambient temperature reaches 140°F (60°C), then the VFD66EBA drive is de-rated
to maximum current of 9.0 amperes due to the high ambient temperature and is
further de-rated to 8.46 amperes because of the high altitude.
De-Rated maximum output amperes = 9.0 amperes x 0.94 = 8.46 amperes.
VFD66 User Guide
Issue Number: 2
50°C
122 F °
Temperature
www.johnsoncontrols.com
VFD66EBA
VFD66CAA
VFD66AAA
60°C
140 F °
21