{"product_id":"rkc-instruments-z-com-a-55-122d-extension-module","title":"Rkc Instruments Z-Com-A-55 122D Extension Module","description":"\u003cdiv\u003e\u003cp\u003eRKC Instruments Z-COM-A-55\/122D SRZ PLC Communication Extension Module is a 24 V DC RS-485 extension device for the SRZ control family, enabling additional host communication by linking Z-TIO, Z-DIO, and Z-CT modules to a single SRZ processor. It is powered from 21.6 to 26.4 V DC (rated 24 V DC) and draws less than 30 mA in normal operation, with surge capability under 10 A to handle power transients. This Z-COM module supports up to 16 units in a network and communicates at selectable baud rates of 4800, 9600, 19200, or 38400 bps using either ANSI X3.28 sub-category 2.5B4 (RKC standard) or MODBUS-RTU protocol, providing flexible interoperability with RKC devices and third‑party masters. Designed for industrial environments, it operates from -10 to 50°C and tolerates supply ripple up to 10% p-p; a power loss of 4 ms or less will not affect control actions, ensuring quick recovery. The Z-COM extension is a specialized data conduit within the SRZ system, serving as the communication backbone for extended configurations that require multiple field devices and robust Modbus\/RS-485 communication capabilities in a compact form factor, and its 122D variant designation identifies this specific configuration of the A-55 family.\u003c\/p\u003e\u003c\/div\u003e","brand":"rKC","offers":[{"title":"New","offer_id":46284582977770,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0716\/8039\/3450\/files\/GTG-STOCK-023.png?v=1788727428","url":"https:\/\/gtghardware.com\/products\/rkc-instruments-z-com-a-55-122d-extension-module","provider":"GTG Hardware","version":"1.0","type":"link"}