Toshiba TOSVERT VF-AS3 Instruction Manual page 17

2. 2. 3 Signaling
As for the encoder feedback signals, Terminal A and NA are connected for Phase A, Terminal B and NB
are connected for Phase B.
The polarity of the pulse input signal should be as follows.
Non-inverting input side: A, B
Inverting input side: NA, NB
The signal feedback from the encoder should have the waveform shown in Fig.2 in terms of the
motor rotation direction. The encoder installation direction and signal wiring should be done
accordingly.
• Forward rotation or reverse rotation is judged from the feedback pulses of Phase A and Phase
B (2-phase pulse that have 90 degrees of phase difference). Therefore, it should be noted that,
when connections are wrong, there is possibility for abnormal rotation of the motor.
Important
Phase A(V )
A
Forward rotation
Phase B(V )
B
A
A
A
NA
B
B
B
NB
Fig.2 - Judge on normal and reverse rotations by the encoder
Phase A(V
Reverse rotation
Phase B(V
V
A
PG
V
B Phase difference : Xn>= 0.15T(n= 1,2,3,4)
feedback of two phases (Phases A and B)
2-5
)
A
)
B
X X X X
1 2 3 4
T
2. Connection to the Inverter
E6582148
2
3
9
10