Omron SYSDRIVE 3G3JV, Communications Manual

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Chapter 1
1-3
Communications Methods
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Transmission Procedure
When the host computer transmits a command frame, the 3G3JE transmits a response frame that
corresponds to the command frame. A single response frame is returned for each command frame.
The following diagram shows the operation of the command and response frames.
Note Allow a wait time of at least 2 ms before the next command is sent after the host computer
receives a response from the 3G3JE.
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Interface
A K3SC Interface Converter is recommended for RS-485/RS-232C (or USB) interface conversion.
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Connections and Wiring
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Connections
• Make the connections according to the host computer and 3G3JE communications specifications.
• The connection format can be either 1:1 or 1:N.
• Up to 32 nodes including the host computer can be connected in a 1:N system.
• When connecting in a 1:N system, make sure that the communications specifications are the same
for all the nodes that are connected. In addition, set a communications unit number for each node.
(For details, refer to the communications setting items for the communications unit number setting.)
• Use shielded twisted-pair cable for RS-485 signal wires.
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Wiring
• The total cable length is 500 m max.
• Use shielded twisted-pair cable with a wires size of AWG24 to AWG16.
• Do not solder the ends of power lines. Doing so may result in faulty contact.
• For ease of wiring and enhanced reliability, it is recommended that solderless terminals be crimped
to the control circuit wires.
• When solderless terminals are not used, the end of each wire for the control lines must be stripped
for approximately 6 mm.
• Cover the shield with tape so that the shield will not come into contact with other signal wires or
machines.
Name Model Description
K3SC Interface Converter
(OMRON) K3SC This Converter is used to convert RS-232C (or USB) to RS-485.
Command frame Command frame
Response frame
Host computer
3G3JE