Epson RC90 User Manual

2. Installation
RC700 / RC90 Option Fieldbus I/O Rev.14 21
Total Drop Line Length
Total drop line length is the total distance of all drop lines in one network.
Trunk Line
2 m
2 m
1 m
1 m
3 m
4 m
4 m
Terminating
Resistor
Terminating
Resistor
In the figure above, the total drop line length is 17 m.
The maximum total drop line length is restricted by baud rate as shown in the table below.
The cable thickness is not related to the restriction.
Baud Rate
Max. Total Drop Line Length
500 kbps
250 kbps
125 kbps
39 m
78 m
156 m
Cable Current Capacity
Current-carrying capacity of the DeviceNet network cable is restricted as below:
Trunk Line
Drop Line (Unit: A)
Thick Cable
Thin Cable
Current Capacity
8A
3A
4.57 / Drop Line Length (m) ≤ 3A
Following figures illustrate examples of power supply configuration.
When an external power supply is installed in the network as shown in the figure below,
the current capacity is 11A and it exceeds the permissible current of the cable.
Trunk Line
1A
Power Supply Tap
External Power
Supply 24 V DC
1A
1A
2A 2A
2A
2A
Terminating
Resistor
Terminating
Resistor
If the location of the external power supply is changed as shown in the figure below, the
power supply can be used because the current capacity on the left side of the power supply
tap is 5 A and 6 A on the right side.
Trunk Line
1A
Power Supply Tap
1A
1A
2A 2A
2A
Terminating
Resistor
External
Power Supply
24 V DC
2A
Terminating
Resistor

Epson RC90 Specifications

General

Brand	Epson
Model	RC90
Category	Controller
Language	English