Omron EJ1 User Manual

179
Determining the Error from the Current Situation for Communications Errors
Section 7-4
Programless
Communications
No Programless Communications between the PLC and the EJ1
Status Possible cause Countermeasure
No communications between
the PLC and the EJ1.
Connection
Connection port
There is no power supply to
the EJ1.
Supply power from the EDU power
supply terminal.
The Serial Communications
Board (SCB)/Unit (SCU) wir-
ing is incorrect.
Refer to the respective manuals and
wire the connection correctly.
See Related Manuals on page xiv.
The port C communications
are set to RS-485.
Turn ON pin 8 on the HFU settings
switch 2 (SW2) to set to RS-232C.
The Serial Communications
Board (SCB)/Unit (SCU) RS-
485 port is connected to the
EJ1 RS-232C port.
Connect the SCU RS-232C port to
the EJ1 RS-232C port.
The EJ1 programless commu-
nications parameters are
incorrect.
Refer to 5-1 Programless Communi-
cations in SECTION 5 Advanced Unit
(HFU) Functions and check the set-
tings.
The Serial Communications
Board (SCB)/Unit (SCU) com-
munications settings are
incorrect.
Same as above.
No communications between
the PLC and the EJ1.
Connection
or
Connection port
There is no power supply to
the EJ1.
Supply power from the EDU power
supply terminal.
The Serial Communications
Board (SCB)/Unit (SCU) wir-
ing is incorrect.
Refer to the respective manuals and
wire the connection correctly.
See Related Manuals on page xiv.
The port C communications
are set to RS-232C.
Turn OFF pin 8 on the HFU settings
switch 2 (SW2) to set to RS-485.
The Serial Communications
Board (SCB)/Unit (SCU) RS-
232C port is connected to the
EJ1 RS-485 port.
Connect the SCU RS-485 port to the
EJ1 RS-485 port.
Alternatively, connect the RS-422A
Converter to the RS-232C port to
convert to RS-485, then connect to
the EJ1 RS-485 port.
The EJ1 programless commu-
nications parameters are
incorrect.
Refer to 5-1 Programless Communi-
cations in SECTION 5 Advanced Unit
(HFU) Functions and check the set-
tings.
The Serial Communications
Board (SCB)/Unit (SCU) com-
munications settings are
incorrect.
Same as above.
EJ1
(RS-232C)
PC
PLC
CS/CJ
SCB/SCU
Connection
port
SCU ---
EJ1
(HFU)
Port C
(RS-232C)
EJ1
(RS-485)
PC
PLC
CS/CJ
SCB/SCU
EJ1
(RS-485)
PC
PLC
CS/CJ
SCB/SCU
CJ1W-CIF11
RS-422A Converter
Connection
port
SCU ---
EJ1
(HFU)
Port C
(RS-485)

Omron EJ1 Specifications

General

Brand	Omron
Model	EJ1
Category	Temperature Controller
Language	English