
EIR203 Series Quick Start 
Guide 
Package Contents 
• EIR203 Series Industrial, Unmanaged, Ethernet Switch 
• Quick Start Guide (One per shipment) 
• Power Terminal Block (installed) 
• Fiber Optic Dust Covers (installed on fiber optic models) 
If any item is missing or damaged, contact B&B Electronics 
for a replacement 
EIR203 (3 Fiber) 
1  Power Terminal Block  2 Position, Removable  
2  PWR LED  ON When Power Applied  
3  Fiber Optic SPD LED  Normally OFF (100BaseFx)  
3  Fiber Optic LINK LED  ON When Fiber Port Linked  
4  Fiber Ports  Number and type depends on Model  
5  RJ45 Ports  Number depends on model  
6  RJ45 LINK LED  On when RJ45 Port Linked  
    Flashes When Data Transmitted 
6  RJ45 SPD LED  On if 100 mbps 
Front Panel 
EIR203 (1 Fiber, 2 RJ-45)
DIN Rail Mounting 
B&B ELECTRONICS    QUICK START GUIDE
© 2008 by B&B Electronics. All rights reserved. 
1. Slide and hold the DIN clip toward the bottom of the 
switch. Angle the top portion of the DIN mount over the 
top of DIN Rail. 
2. Move the switch so that it is parallel with the DIN Rail. 
3. Let go of the DIN Clip. The spring should return it to its 
original position.  
EIR203 1308qsg-1/2 
Attach Power Leads 
External Supply Required 
Warning: Work Safe – Equipment 
damage or electrical shock hazard 
exists. DO NOT ATTACH OR REMOVE 
LEADS WITH THE POWER SUPPLY 
ENERGIZED! 
1. Loosen the screw to open the terminal block lead clamp. 
2. Insert the power lead. TB will accept 12-28 AWG wire. 
3. Tighten the screw to close the terminal block lead clamp. 
Ensure the clamp holds the lead securely. However, do not 
over tighten. 
NOTE: For replacement Terminal Block order Part # 7444. 
Attach RJ45 Cable 
If equipped) 
MDI Cable Pinout 
Pin Signal 
1 Tx+ 
2 Tx- 
Female RJ45 
1. Auto MDI/MDI-x is 
supported. A straight 
through or cross-over 
cable may be used. 
2. 10/100BaseT auto 
negotiation and full/halfduplex are supported. 
3 Rx+ 
6 Rx- 
MDI-X Cable Pinout 
Pin Signal 
1 Rx+ 
2 Rx3 Tx+ 
6 Tx- 
815-433-5100 Fax 433-5104 www.bb-elec.com orders@bb-elec.com support@bb-elec.com 
International Headquarters: 707 Dayton Road PO Box 1040 Ottawa, IL 61350 USA 
European Headquarters: Westlink Commercial Park Oranmore Co. Galway Ireland
           +353 91 792444 Fax +353 91 792445 
www.bb-europe.com orders@bb-europe.com support@bb-europe.com

Attach Fiber Optic Cable 
if equipped) 
Warning: Work Safe – Fiber Optic 
equipped models are Class I 
Laser/LED devices. To avoid causing 
serious damage to your eyes, DO NOT 
STARE DIRECTLY INTO THE LIGHT. 
1. Slider Guide 
2. Slider Ridges
3. Slide
1. Ensure your fiber optic cable is terminated with 
the correct connector type. EIR203 switches use 
SC or ST connectors. 
2. Fiber optic type for each port is located on the 
product’s side label. When connecting the cable 
to the switch, be sure to line up the slider guide 
on the cable and switch connectors. 
3. Connect the fiber optic transmitter to the 
downstream device’s receiver and vice-versa. 
Mode and Distance  Type  Wavelength 
Multi-mode (2 km)  62.5/125 µm  1310 nm 
Single-mode (15 km)  9/125 µm  1310 nm 
Single-mode (40 km)  9/125 µm  1310 nm 
Single-mode (80 km)  9/125 µm  1550 nm 
  Output Power  RCVR Sensitivity  
Multi-mode (2 km)  -19 to -14 dBm  ≤ -32 dBm 
Single-mode (15 km)  -15 to -8 dBm  ≤ -32 dBm 
Single-mode (40 km)  -5 to 0 dBm  ≤ -34 dBm 
Single-mode (80 km)  -5 to 0 dBm  ≤ -34 dBm 
Fiber Optic Cable Information 
Installation Complete 
© 2008 by B&B Electronics. All rights reserved. 
EIR203 1308qsg-2/2 
Mechanical Diagram 
B&B ELECTRONICS    QUICK START GUIDE
1. When the network cables are attached and power 
is applied, installation is complete. 
2. The switch will automatically discover network 
devices, populate its MAC address table, and 
pass traffic to the appropriate ports. 
International Headquarters: 707 Dayton Road PO Box 1040 Ottawa, IL 61350 USA 
815-433-5100 Fax 433-5104 www.bb-elec.com orders@bb-elec.com support@bb-elec.com 
European Headquarters: Westlink Commercial Park Oranmore Co. Galway Ireland
           +353 91 792444 Fax +353 91 792445 
www.bb-europe.com orders@bb-europe.com support@bb-europe.com