GE ASTAT XT QT 0008U Series, User Manual, Page: 77 / 123

77
• Application diagrams
8.20.5
ASTAT-XT Connected Inside Delta - Reverse Speed
IMPORTANT! If speed reversing is required, L1, L2 and L3 on the input of the ASTAT-XT can not be switched!
This is because
Phase Sequence Disabled
can not be implemented when ASTAT-XT is connected Inside Delta.
Thus, in order to reverse motor rotation two motor windings need to be switched as shown in the following diagram:
(Winding V1-V2 is switched with winding U1-U2):
Reverse speed with ASTAT-XT connection Inside Delta with bypass contactor to the ASTAT-XT
and Inside Delta contactor.
C1 is a bypass contactor.
C2 is an Inside Delta contactor.
U1-U2, V1-V2, W1-W2 are motor windings.
1L1-2T1, 3L2-4T2, 5L3-6T3 are ASTAT-XT controlled phases.
A, B, C are preparation for bypass to maintain current protection when the ASTAT-XT is bypassed.