Epson RC700, Manual

Page: 287 / 340

4. Troubleshooting (DeviceNet)
RC700 / RC90 Option Fieldbus I/O Rev.14 275
♦
Causes of Error
Possible Cause Examination Method Countermeasure

Voltage drop of
communications
power supply
Measure voltage of
communications power supply at
the master unit.
→ Normal: 11V or more between
V+ and V-

If the voltage is 11 to 14 V, the
unit is a possible cause. Fix the
problem on the unit.
Check voltage of the power
supply.

Disconnected
terminating
resistors

Cable
disconnection

Disconnected
connector

Disconnected
signal wire
(1) Check that terminating
resistors are connected to both
ends of the network.
(2) Measure resistance between
signal wires with
communications power supply
OFF.
→ Normal: 50 to 70 Ω

Measuring point: Connection of
the master

For details, refer to the section
4.1.3.1 Connection Problem .
Fix the problem.
How to find the trouble
point:
Remove the terminating
resistor on one end of the
network. The trouble point
is where resistance changes
from 120 Ω .

Loose connector

Loose signal wire
Check for the connection of
connectors and signal wires.
→ The connectors and signal
wires should be firmly
connected.

Checkpoint: Between the master
and its slaves

For details, refer to the section
4.1.3.2 Loose Connector and
Signal Wire .
Connect the connectors and
signal wires again.

All slaves power
OFF
Measure the power voltage of the
slaves.
(It should be within the range of
sufficient voltage for the slave
operation.)
Supply power to the slaves.

Master unit
configuration
(1) Start applicomIO Console
application and check that the
configuration has no
difference with the network
condition.
(2) Check that the configuration
data were written in flash.

For details, refer to the section
4.1.3.6 EPSON RC+ Master
Configuration .
Change the configuration.