Delta Electronics VFD-M User Manual

Page 95

Chapter 4 Parameters|

4-60

Revision May 2008, ME14, SW V3.04

Each drive has a built-in RS-485 serial interface, marked (RJ-11 Jack) on the control terminal

block, whose pins are defined as shown:

1: +15V
2: GND

3: SG-
4: SG+

5: NC

6: for communication

Either ASCII or RTU Modbus protocols are used for communication. Users can select the

desired mode along through parameters Pr.92 and Pr.113.

Each VFD-M AC drive has a pre-assigned communication address specified by Pr.88. The

master controller communicates with each AC drive according to its particular address.

Code

Meaning:

ASCII mode:

Each 8-bit data is the combination of two ASCII characters. For example, a 1-byte data: 64 Hex,

shown as ‘64’ in ASCII, consists of ‘6’ (36Hex) and ‘4’ (34Hex).

Character ‘0’ ‘1’ ‘2’ ‘3’ ‘4’ ‘5’ ‘6’ ‘7’

ASCII code

30H

31H

32H

33H

34H

35H

36H

37H

Character ‘8’ ‘9’ ‘A’ ‘B’ ‘C’ ‘D’ ‘E’ ‘F’

ASCII

code 38H 39H

41H

42H

43H 44H

45H

46H

RTU mode:

Each 8-bit data is the combination of two 4-bit hexadecimal characters. For example, 64 Hex.

2. Data Format

2.1 10-bit character frame (For 7-bit character):

( 7.N.2 : Pr.92=0)

( 7.E.1: Pr.92=1)

Start
bit

Stop
bit

10-bit character frame

( 7.O.1:Pr.92=2)

Odd

parity

Start
bit

Stop
bit

10-bit character frame

Even

parity

Start
bit

Stop
bit

7-bit character

10-bit character frame

Stop
bit

7-bit character