Introducing CTM-530 Interface Modules Enhanced with Modbus Over RS-485


Protectowire FireSystems is pleased to announce that all new CTM-530 Modules currently being manufactured have been upgraded to include Modbus over RS-485 communications capability.
RS-485 is a standard defining the electrical characteristics of drivers and receivers for use in serial communications systems. RS-485 allows for installation of extensive local network systems and supports multi-drop communication links. RS-485 has been widely adopted in many industries as the underlying physical layer of industrial automation networks and can span distances of up to 4,000 feet (1,220m) without repeaters.

Modbus is a serial communications protocol originally for use with programmable logic controllers (PLCs). Simple and robust, it has become a de facto standard communication protocol and is now a commonly used means of connecting industrial electronic devices. The new enhanced CTM-530 Interface Modules can be configured as a Modbus slave device on an RS-485.

Once configured to communicate on a network, each module can be polled by a master device for a variety of module specific data. A master device, such as a PLC (Programmable Logic Controller) can monitor the status of one or more modules and take actions based on their status. This type of communication is a convenient method for utilizing detector status information to implement equipment shutdown or other automation events. The enhanced CTM-530’s are available for immediate shipment with no increase in price.

Datasheet: CTM Module w/ Modbus RS-485

Protectowire FireSystems is the originator of Linear Heat Detectors and the leading manufacturer of Special Hazard Linear Heat Detection Systems. Our solutions include complete alarm systems for fire protection suitable for a vast array of industrial and commercial applications. Our products are made in the USA at our factory located in Pembroke, Massachusetts. For over 75 years, many of the world’s largest companies have chosen Protectowire to protect their valuable assets and business operations. If you would like more information, please visit or call 781-826-3878.

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