{"product_id":"honeywell-621-9938r-serial-i-o-module","title":"Honeywell 621-9938R Serial I\/O Module","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eThe\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eHoneywell 621-9938R Serial I\/O Module (SIOM)\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eprovides reliable serial communication for\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eUCN\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003esystems, including\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eTDC 3000\u003c\/strong\u003e. It links remote I\/O card files with processor card files through high-speed serial channels. The module ensures robust data transfer and supports redundant operation when paired with the\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e621-9939 SLM\u003c\/strong\u003e. Engineers use it in distributed control applications where stability and scalability are critical.\u003c\/p\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eModel\u003c\/strong\u003e: 621-9938R\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eManufacturer\u003c\/strong\u003e: Honeywell\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eModule Type\u003c\/strong\u003e: Serial I\/O Module (SIOM)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eCommunication Protocols\u003c\/strong\u003e: RS-232, RS-485, optional CAN in some setups\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eInput Voltage\u003c\/strong\u003e: 24 VDC\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eCurrent Consumption\u003c\/strong\u003e: Approx. 300 mA\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eDimensions\u003c\/strong\u003e: 1.5\" × 10.5\" × 6.5\" (3.8 × 26.7 × 16.5 cm)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eWeight\u003c\/strong\u003e: 1.85 lbs\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eI\/O Capacity\u003c\/strong\u003e: Supports 8, 16, or 32-point configurations\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eRedundancy Support\u003c\/strong\u003e: Dual communication ports; interfaces with 621-9939 SLM\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eDIP Switch Settings\u003c\/strong\u003e:\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003eSW1: Starting address (0–2032, increments of 8)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSW2: Fault response and test mode\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSW3–SW5: I\/O points per slot\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eTermination Requirements\u003c\/strong\u003e: 200 or 300 Ω resistors at channel ends\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eInstallation Notes\u003c\/strong\u003e:\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003eInstall in slot N of remote serial I\/O card file\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eUse Serial Link Selector\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e621-9928R\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003efor dynamic switching\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eDo not mix 8\/16-point modules in 32-point slots\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/ul\u003e","brand":"HONEYWELL","offers":[{"title":"Default Title","offer_id":42278630916186,"sku":"621-9938R","price":209.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0612\/4601\/3530\/files\/621-9938R.jpg?v=1757487765","url":"https:\/\/www.plcmasters.com\/uk\/products\/honeywell-621-9938r-serial-i-o-module","provider":"PLC Masters Ltd.","version":"1.0","type":"link"}