1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the ADTRAN TSU 600 Modular T1/FT1 DSU/CSU. The TSU 600 is a versatile data service unit/channel service unit designed for T1 and fractional T1 network access, offering robust connectivity and multiplexing capabilities for various network environments.
2. Safety Information
- Ensure the device is connected to a grounded power outlet.
- Do not expose the unit to moisture or extreme temperatures.
- Only qualified personnel should perform installation and maintenance.
- Disconnect power before cleaning or servicing the unit.
3. Package Contents
Verify that all items are present in the package:
- ADTRAN TSU 600 Modular T1/FT1 DSU/CSU Unit (Model: 1202076L2)
- Power Adapter/Cord
- Documentation (this manual or quick start guide)
4. Product Overview
The ADTRAN TSU 600 is a compact networking device designed for reliable T1/FT1 connectivity. Its front panel features indicators and controls for monitoring and basic configuration.

Figure 1: Front view of the ADTRAN TSU 600 Modular T1/FT1 DSU/CSU unit. This image displays the beige-colored rectangular device with a small LCD screen on the left, a grid of buttons in the center, and a series of LED indicators on the right side of the front panel. The bottom edge features ventilation slots.
4.1 Front Panel Indicators and Controls
- LCD Display: Provides status information and menu options.
- Navigation Buttons: Used to navigate menus and adjust settings.
- LED Indicators: Display operational status for power, T1 line, data activity, and alarms. Refer to the detailed LED status guide in Section 5.2.
5. Setup
5.1 Physical Installation
- Placement: Position the TSU 600 on a flat, stable surface or mount it in a standard equipment rack (if applicable hardware is used). Ensure adequate ventilation around the unit.
- Power Connection: Connect the provided power adapter to the unit's power input and then to a suitable electrical outlet. Do not power on the unit until all other connections are made.
5.2 Cable Connections
- T1/FT1 Line: Connect the T1 or fractional T1 line from your service provider to the designated T1/FT1 port on the TSU 600.
- Data Interface: Connect your data equipment (e.g., router, multiplexer) to the appropriate data interface port(s) on the TSU 600 using compatible cabling (e.g., Ethernet, serial).
5.3 Initial Configuration
Upon powering on, the TSU 600 will perform a self-test. Basic configuration can be performed via the front panel LCD and buttons. For advanced configurations, refer to the comprehensive ADTRAN TSU 600 Command Line Interface (CLI) guide or web interface documentation, if available for your specific firmware version.
6. Operating
6.1 Powering On and Off
- Power On: After all connections are secure, connect the power cord to the electrical outlet. The unit will power on automatically.
- Power Off: Disconnect the power cord from the electrical outlet.
6.2 Understanding LED Indicators
The front panel LEDs provide quick visual status of the unit's operation:
- Power LED: Solid Green indicates power is on.
- T1/FT1 Link LED: Solid Green indicates a stable T1/FT1 link. Flashing Orange may indicate a link issue or synchronization attempt. Solid Red indicates a critical line alarm.
- Data Activity LEDs: Flashing Green indicates data transmission or reception on the respective port.
- Alarm LED: Solid Red indicates a system fault or major alarm. Consult the LCD for details.
7. Maintenance
7.1 Cleaning
To maintain optimal performance, periodically clean the exterior of the unit with a soft, dry cloth. Do not use liquid cleaners or solvents. Ensure ventilation slots are free from dust and obstructions.
7.2 Firmware Updates
Firmware updates may be released to improve performance or add features. Refer to the ADTRAN support website for the latest firmware and instructions on how to apply updates. Always back up your configuration before performing a firmware update.
8. Troubleshooting
This section addresses common issues you might encounter with the ADTRAN TSU 600.
- No Power:
Ensure the power cord is securely connected to both the unit and a working electrical outlet. Verify the outlet has power.
- T1/FT1 Link Down (Link LED is Red or Off):
Check the T1/FT1 cable connection. Contact your service provider to verify the line status. Ensure the unit's configuration matches the service provider's line settings.
- No Data Transmission:
Verify that the data interface cables are correctly connected. Check the data activity LEDs. Confirm that the connected data equipment is operational and configured correctly to communicate with the TSU 600.
- System Alarm (Alarm LED is Red):
Consult the LCD display for specific alarm messages. Refer to the ADTRAN TSU 600 technical documentation for detailed alarm code explanations and resolutions.
9. Specifications
Key technical specifications for the ADTRAN TSU 600 Modular T1/FT1 DSU/CSU (Model: 1202076L2).
| Feature | Specification |
|---|---|
| Brand | ADTRAN |
| Model Number | 1202076L2 |
| ASIN | B0000516BX |
| Product Type | Electronic Switch / DSU/CSU |
| Connectivity Protocol | X-10 (Note: This may refer to control method, not primary data protocol) |
| Connector Type | Plug In |
| Mounting Type | Plug In Mount |
| International Protection Rating | IP54 |
| Item Weight | 18.4 pounds (8.35 kg) |
| Package Dimensions | 22 x 18 x 9.5 inches (55.88 x 45.72 x 24.13 cm) |
| UPC | 607565000096 |
| Date First Available | September 4, 1973 |
10. Warranty Information
ADTRAN products typically come with a limited warranty. For specific warranty terms and conditions applicable to your TSU 600 unit, please refer to the warranty card included with your product or visit the official ADTRAN website. Keep your proof of purchase for warranty claims.
11. Support
For technical assistance, additional documentation, or to report issues, please contact ADTRAN Technical Support. You can find contact information and resources on the official ADTRAN website:
- ADTRAN Website: www.adtran.com





