Danfoss VLT AutomationDrive FC 300 User Manual

A number of data bytes (variable, depending on the type
of telegram) follows.
A data control byte (BCC) completes the telegram.
STX LGE ADR DATA BCC
195NA099.10
Illustration 7.5
7.3.3 Telegram Length (LGE)
The telegram length is the number of data bytes plus the
address byte ADR and the data control byte BCC.
Data Length
4 data bytes LGE = 4 + 1 + 1 = 6 bytes
12 data bytes LGE = 12 + 1 + 1 = 14 bytes
Telegrams containing texts
10
1)
+n bytes
Table 7.3
1)
The 10 represents the fixed characters, while the “n’” is variable
(depending on the length of the text).
7.3.4
Frequency Converter Address (ADR)
Two different address formats are used.
The address range of the frequency converter is either 1-31
or 1-126.
1. Address format 1-31:
Bit 7 = 0 (address format 1-31 active)
Bit 6 is not used
Bit 5 = 1: Broadcast, address bits (0-4) are not
used
Bit 5 = 0: No Broadcast
Bit 0-4 = frequency converter address 1-31
2. Address format 1-126:
Bit 7 = 1 (address format 1-126 active)
Bit 0-6 = frequency converter address 1-126
Bit 0-6 = 0 Broadcast
The slave returns the address byte unchanged to the
master in the response telegram.
7.3.5
Data Control Byte (BCC)
The checksum is calculated as an XOR-function. Before the
first byte in the telegram is received, the Calculated
Checksum is 0.
7.3.6
The Data Field
The structure of data blocks depends on the type of
telegram . There are three telegram types, and the type
applies for both control telegrams (master⇒slave) and
response telegrams (slave⇒master).
The 3 types of telegram are:
Process block (PCD)
The PCD is made up of a data block of 4 bytes (2 words)
and contains:
- Control word and reference value (from master to
slave)
- Status word and present output frequency (from
slave to master)
ADRLGESTX PCD1 PCD2 BCC
130BA269.10
Illustration 7.6
Parameter block
The parameter block is used to transfer parameters
between master and slave. The data block is made up of
12 bytes (6 words) and also contains the process block.
PKE INDADRLGESTX PCD1 PCD2 BCC
130BA271.10
PWE
high
PWE
low
Illustration 7.7
RS-485 Installation and Set... VLT Automation Low Harmonic Drive Operating Instructions
134 MG34O202 - VLT
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Danfoss VLT AutomationDrive FC 300 Specifications

General

Brand	Danfoss
Model	VLT AutomationDrive FC 300
Category	DC Drives
Language	English