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SER485 MODBUS
SER485/Modbus

Modbus interface

  • Directly connect your HVAC systems to your Qbus system
  • Compatible with Daikin, Mitsubishi, Fujitsu, and many more
  • With pre-programmed Modbus commands
  • Suitable for heating, cooling, ventilation, and more
Technical info

Module to integrate Qbus with devices that have a Modbus (SER485) port. The Modbus data from various devices (Daikin, Toshiba, Mitsubishi, Fujitsu, Priva, Robur) is standard in the Qbus module, for others the code must be added by Qbus.

Technical info for installers

  • Function description

    Module to integrate products with a Modbus (SER485) interface into a Qbus installation. The specific Modbus commands from various devices are standard integrated in the SER485 (e.g. Daikin RTD, Toshiba, Mitsubishi, Fujitsu, Priva, Robur,…). Through a dropdown box, the correct Modbus commands for the module to be integrated can be selected. Additional Modbus commands are regularly integrated into the Qbus Modbus Interface Module upon customers' request. Each SER485/Modbus module has a unique serial number, allowing programming anywhere and anytime. All programmed data is internally stored in permanent memory

  • Technical specifications

    General Specifications 

    • Power Supply: bus
    • Ambient Temperature: Operating Temperature: 10°C to 50°C Storage Temperature: -10°C to 60°C
    • Maximum Humidity: 93%, no moisture condensation
    • Bus Power: 30 mA nominal at 13.8 V • Max. mounting height: 2,000 meters. 

    SER485/Modbus Connections

    • A maximum of 64 Modbus registers can be controlled by one SER485/Modbus module. It is necessary to verify how many Modbus registers need to be controlled per external device (usually 5-8) to calculate the total number of external devices that can be controlled by one SER485/Modbus.
    • The maximum distance between the SER485/Modbus and the external module is 1000m.
    • The connection between the SER485/Modbus and the external module can be laid in either a loop or a star configuration.

     Physical Specifications: 

    • Housing: plastic, self-extinguishing according to UL94-V0 • Protection degree: IP20, EN60529
    • Installation: quick mounting on DIN rail, width 2 modules
    • Dimensions (H x W x L): 62 mm x 90 mm x 36 mm • Weight: approximately 0.072 kg 

    CE:  

    • Bus: 13.8 VDC low voltage
    • Non-toxic, in compliance with WEEE/RoHS
    • Compliant EN 60730-1:2000-11 +A11 2002
  • Sizing
    SER485 Dimensionering MODBUS
  • Explanation of symbols
    Symbool Dubbele isollatie

    Equipment where protection against the risk of electric contact is not only based on basic insulation but also on additional protection such as double insulation or reinforced insulation. There is no possibility for grounding.

     

    Symbool Gevaar Aandachtig lezen

    Before connecting the device, it is mandatory to read the manual of the respective product. ISO7000-0434

    Symbool Gevaarlijke spanning

    Power supply connection (230V) to the power supply connector. IEC 60417-5036

    Symbool CE

    CE conformity. All declarations of conformity are available upon request.

  • Warranty provision

    2 years from the date of delivery. The warranty becomes void if the module has been opened! The warranty period is extended by 2 years if it was installed by a certified Qbus installer.

    In case of defects, Qbus support should be contacted by a certified installer. After registration with Qbus support, the defective module can be sent, unsealed and with a description of the defect, to our Qbus support.

    Contact details:       

    Qbus NV

    Joseph Cardijnstraat 19

    B-9420 Erpe-Mere

    Tel: +32 (0)53 60 72 10

    Fax: +32 (0)53 60 72 19

    Email: support@qbus.be

General

  • Safety regulations

    Read the entire manual before installing and activating the module. 

    WARNING

    •  Installation, commissioning, and maintenance of the devices must be carried out by a qualified electrician in accordance with the applicable legal requirements.
    • This device is exclusively suitable for DIN rail mounting according to EN50022. It must be mounted in a fire-resistant distribution panel with ventilation openings.
    • Do not open the device. The warranty will be void if the module is opened.
    • Risk of electric shock upon contact with live parts.

Installation and wiring

  • Installation

    Snap the module onto a DIN rail DIN EN50022.

  • Power supply

    The SER485/Modbus is powered by the bus

  • RS485/MODBUS

    The wiring between the Modbus port on the external device and the RS485 connector on the Qbus Modbus interface should be done with solid conductors of up to 0.8 mm². Use a CAT5 cable for this. The green EIB cable can also be used for this purpose (use the conductors individually).

  • Bus connection

    It is recommended to use the Qbus cable or any other cable with a minimum of 2 conductors of 1mm² as the bus cable. The green shielded EIB cable can also be used if the conductors are paired to achieve a minimum cross-section of 2 x 1mm².

Wiring diagram

  • Wiring diagram

    General cabling example

    P54 SER485 MODBUS

    Specific example of cabling with Daikin RTD modules

    P54 SER485 MODBUS met Daikin

Each modules has an unique serial number. By this number the System Manager recognizes the modules.

This is completely explained in our knowledge center.

After entering the serial number or selecting the module, following screen appears:

Qbus System Manager III Manual Update 04 2025 pdf image 412

The SER485/Modbus module can link up to 127 Modbus registers at different slave addresses to a qbus I/O. Known types are preconfigured in the file “ModbusTypes.Json”
This file can be customized to your preference. When one of these types is selected, the registers, function codes and conversions are fixed. Only the correct Qbus I/O has to be selected.
If you choose the – Custom – all settings are completely free.

The name of the slave address can be changed at the top of the Tab, as well as copying the settings from another slave address is possible.

When clicking on “Read values”, both the modbus register will be read and displayed (in the column “Modbus St.) and the status of the Qbus IO (in the penultimate column).
In the last column you can (temporarily) disable certain lines. When sending the configuration of the module, these lines will not be sent, but they will remain in the configuration on the PC.