Modbus protocol is an open protocol widely used in industrial or process control language (PCL) applications. Modbus devices communicate over a serial netwok in a master/slave (request/response) type relationship using one of two transmission modes: ASCII (American Standard Code for Information Interchange) or RTU (Remote Terminal Unit (RTU) mode. Up to a one-second interval can occur between transmissions without causing communication errors.
McQuay MicroTech II® chiller unit controllers with the optional Modbus communication module communicate using the RTU mode. Modbus integration information for McQuay equipment is available on each product page by clicking on the Control Integration link.
Visit the Modbus web site.