{"product_id":"siemens-505-6851a-remote-base-controller-5056851a","title":"Siemens 505-6851A Remote Base Controller","description":"\u003cdiv\u003e\u003cp\u003eSiemens 505-6851A Remote Base Controller is a stand-alone or redundant RBC used in the SIMATIC TI505‑based 545\/555\/575 I\/O systems to extend remote I\/O across RS‑485 to a central Series 505 controller. It enables linking up to 15 additional remote I\/O bases, and a remote I\/O arrangement can handle 256 discrete inputs and 256 discrete outputs across two remote bases with updates in about 3 milliseconds at a 1 megabaud data rate, ensuring real-time synchronization with the controller’s scan. The 505‑6851A version employs a thumbwheel to set the base address, while the 505‑6851B uses a rotary switch, and the unit provides RS‑232 and I\/O ports along with a modem F‑connector for optional dial‑up communications. Power options include a stand‑alone DC supply (PPX:505‑6663) or a redundant 110\/220 VAC supply (PPX:505‑6660‑A); the 110\/220 VAC supply cannot be used in a redundant configuration. Designed for TI505 controllers, the RBC sits in the remote I\/O architecture and supports synchronous updates across remote bases, making it well suited for distributed automation where multiple remote bases must be coordinated from a single controller. \u003c\/p\u003e\u003c\/div\u003e","brand":"SIEMENS","offers":[{"title":"Used Surplus - Excellent Condition","offer_id":46268225552618,"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-017.png?v=1788727429","url":"https:\/\/gtghardware.com\/products\/siemens-505-6851a-remote-base-controller-5056851a","provider":"GTG Hardware","version":"1.0","type":"link"}