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4TO (BACnet MSTP / Modbus RS485)


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4TO (BACnet MSTP / Modbus RS485)


Multiprotocol I/O Module in a Compact Size
Powerful I/O module that works as a remote I/O over a serial port with open protocols, BACnet MS/TP and Modbus RTU/ASCII. A compact size and ease of installation allow the module to be fitted even into limited space installations.

4 Triac Outputs 
Silent control of AC current with four solid-state outputs with PWM mode and up to 0.5 A load.

Manual Override Switches 
Each output can be manually overridden using a dedicated hand operating switch.

Simplified Configuration and Commissioning Process
The module allows for seamless configuration over BACnet, Modbus or dedicated free of charge tool. The ability to be powered from a USB port facilitates local testing and a straightforward updating process, and the high-end RS485 transceiver allows up to 128 devices to communicate reliably with the client on a single bus.


Technical Specification
Hardware Specification
RS485 interface
mini USB type B interface
Status LED indicators
DIN rail mounted

4 Triac Outputs (TO) 
0.5 A @ 24 V AC, 0.5 A @ 230 V AC
Continuous load per channel: 0.5 A (1.5 A peak 30 s) 
Switching voltage: 20 to 250 V AC

Free software iSMA Configurator
Dedicated Niagara Framework modules

Power Supply
24 V DC ± 20%
24 V AC ± 20%


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