Johnson Controls Metasys N2 - Page 2

2
Network Communications—N2 Communications Bus
Troubleshooting Procedures Page *51
• Overview *51
• Checking for Good Wire Runs 51
• Checking for Proper Termination 52
• Checking the End-of-Line Device Settings 52
• Checking for Proper Channel Selection 52
• Checking the N2 Device 52
• Checking the Number of Defined N2 Devices 52
• Checking the Length of N2 Bus *53
• Checking for “T” or “Y” Connections 53
• Checking for a Ground Loop 53
• Checking the Repeater 53
• Checking the Surge Protector 53
• Checking the Communication Terminal Board 54
• Checking Communication Faults *55
Ordering Instructions 57
• Johnson Controls Code Numbers 57
• Vendor Code Numbers *57
• Repair Parts *58
* Indicates those sections where changes have occurred since the last printing.