Omron E5*C Series Communications Manual

1 - 3
1 Communications Methods
E5C-T Digital Temperature Controllers Programmable Type Communications Manual (H186)
1-1 Overview of Communica-
tions Methods
1
1-1-3 Transmission Procedure
When the host transmits a command frame, the E5@C-T 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.
Communications with the host are carried out through a standard RS-485 interface. Use a K3SC Inter-
face Converter for RS-485 interface conversion.
 RS-485
• The RS-485 connection can be either one-to-one or one-to-N. Up to 32 units including the host
can be connected in a one-to-N system.
• The total cable length is 500 m max.
• Use a shielded twisted-pair cable with a wire gauge of AWG24 to AWG18 (cross-sectional area of
0.205 to 0.823 mm
2
).
E5CC-T/EC-T/AC-T
1-1-3 Transmission Procedure
1-1-4 Interface
1-1-5 Wiring
E5@C-T
Command frame
Command frame
Response frame
Host
Allow a wait time of at least 2 ms before the next command is sent after the host
receives a response from the E5@C-T.
RS-485
14
13
RS-485
6.8 V
TX
RX
14
13
FG
−
+
SG
A (−)
B (+)
A (−)
B (+)
120 Ω
(1/2 W)
Abbreviation
Pin
Abbreviation
Specify both ends of the transmission path including the host
as the end node (that is, connect terminators to both ends).
Use a terminating resistance of at least 54 Ω.
Host
E5CC-T/EC-T/AC-T
E5CC-T/EC-T/AC-T
End node
RS-485
Shield
Shield
Terminator
Use a 120 Ω (1/2 W)
terminator.
A < B: "1" Mark
A > B: "0" Space
Communications
transceiver
Pin
Abbreviation

Omron E5*C Series Specifications

General

Brand	Omron
Model	E5*C Series
Category	Controller
Language	English