4P642495-1A
–
2022.02
Page
3
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52
Safety Precautions
Before performing design, construction, or maintenance thoroughly,
read the “Safety Precautions” in the
installation manual provided with the product.
1. Introduction
A Building Manangement System (BMS) can control Daikin units through the Modbus protocol by using the
Modbus Interface DIII
EKMBDXB7V1.
Glossary:
- BMS: Building Management System
- DIII unit: Unit with DIII communication connected to the Modbus Interface DIII.
- DIII device: A centralised device from Daikin with DIII communication (e.g.
iTM, …)
- Indoor unit: As the main target is to monitor and control VRV connected indoor units, the DIII units are
referred to as
indoor units
. For some systems the connected DIII units are in reality outdoor units (e.g. Applied
units)
1.1 System layout
Typical setup (e.g. VRV)
DIII address (Group NO) needs to be set on an individual indoor unit or group by the connected userinterface.
Functions of each Indoor unit in a range for each register:
Example:
Register address
DIII address functions
31001
–
31003
1-00
31004 - 31006
1-01
…
…
BMS
Outdoor
Outdoor
Indoor
Indoor
Indoor
1-00
1-01
1-02
DIII address
Indoor
Indoor
Indoor
1-03
1-04
1-05
DIII address
Modbus Interface DIII
RS485 Modbus protocol
2 wire, max wire length 500m
DIII indoor
connection
DIII outdoor
connection
One Modbus slave
address
(e.g. 1)
