Introduction; Accessories - Johnson Controls MS-FIT100-0 User Manual

1/7/2021
6. Appendix A
1. MS/TP Communication Basics and the FIT
2. Voltage Levels
3. 1-ON-1 Communication Voltage Levels
4. Tips for Correcting Bus Installation Problems
5. Quick Start Guide
6. FIT Display Table
7. Appendix B: FIT Firmware Update Instructions
1. Programming the FIT
8. Single point of contact

Introduction

The Field Inspection Tool (FIT) is a portable handheld device with a user interface that
is used to test and troubleshoot the BACnet® protocol MS/TP RS-485
communications bus that connects supervisory controllers and field controllers to
field point interfaces.
The FIT can be used to check out the wiring of the MS/TP RS-485 bus as well as verify
proper communications of supervisory controllers and field controllers connected to
the bus. The FIT can be used on both the Field Controller Bus (FCB) and Sensor
Actuator Bus (SAB).
The FIT can perform the following functions on the FC/SA Bus:
Measure bus bias voltage levels
Communicate with controllers and provide:
- Number of Devices Online
- Device addresses
- Model Name
- Application Name
- Firmware Revision
- Status of End of Line (EOL) termination switch
- Measure RS-485 communication voltage levels from controller
- Other controller attributes
Monitor and report communication errors
For more information on MS/TP basics see,

Accessories

https://docs.johnsoncontrols.com/bas/internal/api/webapp/print/b4118696-0b8a-4733-98fb-fdd04b065b15
1. Communication Voltage Levels
2. Idle Bus Voltage Levels
3. Proper EOL Termination
4. FIT Connection, EOL, and Shield Grounding Scenarios
1. Network Communication Voltage Levels
2. Voltage Table
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MS/TP Communication Basics and the FIT.
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