Emerson Control Techniques EN-204, Руководство по установке, Страница: 32 / 89

EN Series Drives Manual
I f the distribution transformer is configured as shown in Figure 13 or Figure
14, an isolation transformer is required.
I f an isolation transformer is used between the power distribution point and
the drives, the transformer secondary must be grounded for safety reasons as
shown in the figures below.
DISFit DUI ION PANEL
r
3 0 ISOLATION TRANSI ORME R
r
L l I
L 3
P E
EARTH J I ( P r o t e c t i v e Ear-11)1
L G R O U N D
Figure 13
. To F u s i n g a n d
EN D r i v e L I Te r m i n a l s
Example 3: Three Phase Delta /Delta (With Midphase GND)
Distribution to a Three phase WYE WYE Isolation
Transformer.
DISTRIBUTION PANEL
T-7
GROUND =
3 0 ISOLA-ION TRANSI ORMFR
(Protect'
I 7
To F u s i n g a n d
EN D r i v e J I T e r m i n a l s
Figure 14 E x a m p l e 4: Three phase Delta WYE (ungrounded) Distribution
to a Three Phase WYE/WYE Isolation Transformer
20