DELTA RS485 UNOnext UNO-7TB Indoor Air Quality Monitor User Manual
- June 3, 2024
- Delta
Table of Contents
RS485 UNOnext UNO-7TB Indoor Air Quality Monitor
User Manual
Delta Electronics, Inc.
UNOnext UNO-7TB
Troubleshooting: RS485
V20220225
RS485 UNOnext UNO-7TB Indoor Air Quality Monitor
UNOnext UNO-7TB supports Modbus RTU and BACnet MS/TP via RS485, and these two protocols run simultaneously. Following the document: UNOnext BACnet use guide, the Building Management System (BMS) system retrieves the UNOnext data RS485 interface. If there is any trouble, please check the items below to verify the environment and device settings in the RS485 bus. All referred documents can be found at https://isdweb.deltaww.com/resources.
Environment Settings
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Check for correct power from the 9-24V DC input or adapter is correct. The requirement of Adapter is output 12VDC/1A. Please refer to Quick start guide about the mechanical specification of mechanical.
If the power supply is normal and the UNOnext hardware is normal, the power led is on. If the power supply is normal but the power led is not on, please send UNOnext back for repair.
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For Modbus RTU, check that the A2 (+) and B2 (-) are properly connected to Modbus RTU client.
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For BACnet MS/TP, check that the A1 (+) and B1 (-) are properly connected to BACnet MS/TP client.
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Check the cable specifications.
It is recommended to use a 22AWG/24AWG multi-core shielded twisted pair cable or above to achieve the best performance for UNOnext. -
Check that the signal and power wire are in the same conduit or not.
It is recommended to separate the signal and power wire into separate conduit. Or use the individual power supply for UNOnext.
Please refer the following suggested RS485 wire specs:
Twisted Pair Cable
- 22-24AWG twisted pair, shielded jacketed communication cable.
- Characteristic impedance of 100-120 ohms.
- Capacitance of 17 pF/ft conductor-to-conductor or less. 18AWG cable does not meeting this specification.
- Braided or aluminum foil shield.
- Velocity of propagation of 66% or higher.
Example compatible cable products are Belden 9841, Belden 82841 and Windy City Wire 42002-S
Device Settings
- Check the Modbus RTU slave address and BACnet MAC address settings.
The Modbus RTU slave address and BACnet MAC Address are set by DIP switch from [2] to [5] in the back of UNOnext. The DIP definition of address is shown as below table.
Modbus Salve Address| BACnet MAC Address| PIN No. of DIP
switches
---|---|---
Decimal| Hexadecimal| Decimal| Hexadecimal| | | |
208| OxDO| 0| Ox00| | | |
209| 0xD1| 1| Ox01| | | |
210| 0xD2| 2| 0x02| | | |
211| 0xD3| 3| 0x03| | | |
212| 0xD4| 4| 0x04| | | |
213| OxDS| 5| Ox05| | | |
214| 0xD6| 6| 0x06| | | |
215| OxD7| 7| 0x07| | | |
216| OxD8| 8| 0x08| | | |
217| OxD9| 9| 0x09| | | |
218| OxDA| 10| OxOA| | | |
219| OxDB| 11| OxOB| | | |
220| OxDC| 12| OxOC| | | |
221| OxDD| 13| OxOD| | | |
222| OxDE| 14| OxOE| | | |
223| OxDF| 15| OxOF| | | |
2. For Modbus RTU, check the UART settings.
The UART settings for UNOnext as:
• Baud: 9600 by default, also supports 38400, 57600, 115200 modified by Modbus
RTU protocol. (See UNOnext BACnet use guide or UNOnext Modbus RTU)
• Data-bit: 8
• Parity: None
• Stop-bit: 1
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For BACnet MS/TP, check the UART settings.
The baud rate of BACnet MS/TP UART settings is set by DIP switch [6] and [7]. Refer to the below table. BACnet MS/TP BaudrateBaudrate| DIP
76800| 6| 7
9600| |
19200| |
38400| | - If the UNOnext daisy-chained for longer distances, please pull up the DIP switch [1] to enable RS485 terminal resister to try.
- Try a factory reset.
If the problem is still not solved after checking and modifying the above device settings, please try to restore the factory settings.
METHOD: After booting, press the reset key three times duration one second to execute factory reset. After factory reset, all settings will be cleaned.
Note. If all actions do not resolve the problem, please contact your dealer for assistance.