Danfoss VLT HVAC Drive FC 100 Series, Руководство по конструкции

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7.3 Network Configuration
7.3.1 Adjustable Frequency Drive Set-up
Set the following parameters to enable the FC protocol for
the Adjustable frequency drive.
Parameter Number Setting
8-30 Protocol FC
8-31 Address 1–126
8-32 Baud Rate 2400–115200
8-33 Parity / Stop
Bits Even parity, 1 stop bit (default)
Table 7.3
7.4 FC Protocol Message Framing Structure
7.4.1 Content of a Character (byte)
Each character transferred begins with a start bit. Then 8
data bits are transferred, corresponding to a byte. Each
character is secured via a parity bit. This bit is set at "1"
when it reaches parity. Parity is when there is an equal
number of 1s in the 8 data bits and the parity bit in total.
A stop bit completes a character, thus consisting of 11 bits
in all.
Figure 7.5
7.4.2 Message Structure
Each message has the following structure:
1. Start character (STX)=02 Hex
2. A byte denoting the message length (LGE)
3. A byte denoting the Adjustable frequency drive
address (ADR)
A number of data bytes (variable, depending on the type
of message) follows.
A data control byte (BCC) completes the message.
STX LGE ADR DATA BCC
195NA099.10
Figure 7.6
RS-485 Installation and Set...
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