WEG MVW3000 A0040 V023, User Manual

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9-16 | MVW3000
9
Communication Networks
9-16 | MVW3000
Diagram:
Inverter
Basic variables
Parameters
Master
Serial connection
Variables
Figure 9.11: Scheme of basic variables
Parameter/Variable Resolutions
During parameter reading/writing their decimal points are disregarded in the values received/sent via telegrams,
whereas the basic variables V04 (Serial Reference) and V08 (Motor Speed) that are standardized as 13 bit (0 to
8191).
Examples:
„
Writing: If the purpose is to change the P0100 content to 10.0 s, 100 must be sent (disregarding the decimal
point).
„
Reading: If 1387 (disregarding the decimal point) is read from P0409, them its value is 1.387.
„
Writing: in order to change V04 content to 900 rpm one must send:
V04 = 900 x 8191 = 4096
P0208
Assuming that P0208 = 1800 rpm
„
Reading: If 1242 is read from V08 the corresponding value is given by:
V08 = 1242 x P0208 = 273 rpm
8191
Assuming that P0208 = 1800 rpm
Character Format
„
1 start bit.
„
8 data bits (they codify text and transmission characters, taken from the 7-bit code, according to ISO 646 and
complemented for even parity [eighth bit]).
„
1 stop bit.
After the start bit goes the least significant bit:
START B1 B2 B3 B4 B5 B6 B7 B8 STOP
Start
bit Stop
bit
8 data bits