WEG MVW3000 A0040 V023, User Manual

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5-2 | MVW3000
5
Synchronous Motor Line
Clock
Data
MSB
BIT 13 BIT 12 BIT 11 BIT 0 Zero Par.
LSB Zero Parity
t1 T
nT
t2
Figure 5.2: Clock specification and data transfer for the absolute encoder
Supply voltage of 15 V, with consumption lower than 300 mA.
Resolution of 14 bits per turn, which ensures a dynamic equivalent to the conventional incremental encoder;
When mounting the encoder next to the motor, it is recommended:
„
Coupling the encoder directly to the motor shaft (using a flexible coupling, however without torsional flexibility).
„
Both the shaft and the metallic frame of the encoder must be electrically isolated from the motor (minimum
distance of 3 mm).
Use good quality flexible couplings that prevent mechanical oscillations or “backlash”.
NOTE!
The standard absolute encoder recommended for the MVW3000 is the Baumer MHAP 400 B5
XXXXSB14EZ D.
The maximum encoder cable length is 120 m.
Refer to the motor project to define the type of encoder mounting.
5.1.2 RSSI Board
The use of absolute encoder implies the need for an SSI data interface (Synchronous Serial Interface) between
the encoder and the inverter. The RSSI board was developed for the encoder specification previously described.
This board has the following features:
Supply voltage of 24 V DC, with consumption of up to 700 mA.
RS485 communication channel for data transmission and clock according to SSI standard with absolute encoder;
2 fiber optic communication channels for use with up to two boards, MVC3 control and FOI3.
For electric connection, use shielded cables, keeping them at least 25 cm away from the other cables (power,
control, etc.). Preferably inside a metal conduit.