Epson RC90 User Manual

4. Troubleshooting (PROFIBUS DP)
RC700 / RC90 Option Fieldbus I/O Rev.14 301
♦ Causes of Error
Possible Cause
Examination Method
Countermeasure
 Electrical surges of
device power supply
Measure voltage of the device
power supply at the trouble
unit.
→ It should be within the range
of sufficient voltage for
device operation.
Check voltage of the device
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
device power supply OFF.
→ Normal: 100 to 120 Ω
 Measuring point: Connection
of the trouble unit
 For details, refer to the
section 4.2.3.1 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 220
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: all stations and
all branch taps
 For details, refer to the
section 4.2.3.2 Loose
Connector and Signal Wire.
Connect the connectors and
signal wires again.

Broken unit
Replace the trouble unit with a
new one.
→ Verify whether the problem
is fixed.
Replace the unit with a new
one.

Epson RC90 Specifications

General

Brand	Epson
Model	RC90
Category	Controller
Language	English