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What is the difference between Open and Closed protocol IO Modules?


What is the difference between Open and Closed protocol IO module?

Closed Protocol 

A Closed Protocol IO module will be part of a stand-alone system where all elements are produced by the same manufacturer and these elements will not be compatible with any other manufacturer’s equipment.  Examples of Closed Protocol manufacturers include Trend, Distech, Schneider and Siemens. 


If you choose to use a Closed Protocol IO you can benefit from a lengthy warranty and because all parts of your system are produced by the same manufacturer, when you have an issue an engineer can run diagnostics across your whole system to isolate and identify the problem.


The drawbacks of choosing a Closed Protocol IO come in the form of restrictions. By being bound to one manufacturer, you will also be restricted in where you can go for repairs and you could find yourself trapped when mandatory upgrades come around or parts become discontinued. This also means that a decision to migrate to another manufacturer will mean a complete change of system.


Open Protocols


An Open Protocol IO module will work with any controller (BACnet or Modbus) and provide you with the flexibility to choose your system components based on the specifics of your requirements.


By choosing an Open Protocol IO Module you can benefit from knowing your product has been well tested to ensure compliance with other systems. 

Open Protocol IOs will also provide you with the flexibility to be able to upgrade the BMS controller, when you decide and without the need to change the rest of the system.

A drawback to using Open Protocols is you may find yourself in a situation where components will no longer be compatible after a system upgrade, or when an engineer call out is required they may be unfamiliar with some of your system components.


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Innon Team

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