Black Box MD650A-13

Overview

The Black Box MD650A-13 is a fiber extender designed to transmit asynchronous RS232, RS422, and RS485 serial signals over single-mode fiber using ST connectors. It enables long-distance communication for control systems, sensors, PLCs, and other serial devices where copper cabling is limited by distance or electrical interference. Supporting data rates up to 10 Mbps for RS422/RS485 and 200 kbps for RS232, it extends serial connections up to 21.75 miles (35 km) while providing electrical isolation to reduce noise and ground loop issues.

Key features

• Supports RS232, RS422, and RS485 protocols with built-in end-to-end protocol conversion to simplify wiring and reduce failure points
• Enables both point-to-point and multipoint network configurations for flexible system design
• Operates in simplex, full-duplex, or half-duplex modes to match various application requirements
• Uses single-mode fiber with ST connectors for long-distance transmission up to 21.75 miles (35 km)
• Provides electrical isolation to protect equipment from ground loops and electromagnetic interference common in industrial environments
• Compact enclosure fits easily into control panels or DIN-rail shelves without occupying excessive space
• Terminal block connectors simplify serial wiring and installation

Key specs

• Supported protocols: RS232, RS422, RS485
• Maximum data rate: 10 Mbps (RS422/RS485), 200 kbps (RS232)
• Fiber type: Single-mode
• Fiber connector: ST
• Maximum range: 21.75 miles (35 km)
• Operating modes: Simplex, full-duplex, half-duplex
• Enclosure dimensions: 1.3 in H × 3.5 in W × 4 in D

Connectivity and compatibility

This extender connects serial devices via terminal block connectors, supporting legacy RS232 equipment alongside newer RS422 and RS485 devices on the same fiber link. The ST fiber connectors ensure compatibility with standard single-mode fiber infrastructure, making it suitable for integration into existing industrial or automation networks.

Ideal uses and environments

The MD650A-13 excels in industrial and commercial settings where serial communication must cover long distances or overcome electrical noise. It is well suited for applications such as SCADA systems, remote sensor monitoring, factory automation, and campus-wide control networks. Its electrical isolation and protocol flexibility make it a strong choice for environments with heavy machinery or mixed serial device types.

Orders are processed within 2 business days, which includes verification, packing, and dispatch. Shipping costs are calculated at checkout based on destination, total weight, and selected speed. Free shipping applies to carts over $100 (excluding heavyweight items). All available options and final pricing are clearly shown before payment so you can choose the service that best fits your needs.

Deliveries are handled by major carriers such as USPS, UPS, and FedEx. Estimated delivery times are displayed at checkout and may vary depending on service level and location. Please note that these are estimates and can be affected by weather, holidays, or carrier volume. Once your order ships, you’ll receive a tracking number for real-time updates from pickup to final delivery.

Providing an accurate shipping address helps prevent delays, and changes may be limited once the order has been dispatched. P.O. boxes are supported only when permitted by the selected carrier. Packaging and handoff are optimized to protect items during transit, though oversized or high-weight products may require special handling. All shipping methods and any related constraints are clearly shown during checkout.

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Returns are accepted within 30 days of delivery. Items must be unused, in the same condition received, and include all tags, manuals, accessories, and original, unaltered packaging. To start a return, please email us for approval. Items sent back without approval may be refused or returned to the sender. If any item is kept, its value will be deducted from the refund.

Non-returnable items include opened TVs, combos, or monitors 37″ or larger, opened computers or software, electronic downloads, opened consumables (film, paper, bulbs, media, ink), custom or modified computers, special-order or “nonreturnable” items, submerged underwater gear, and opened educational media.

After inspection, refunds are issued to the original payment method. Please allow 5–7 business days for the credit to post. Shipping and handling are nonrefundable. If an item is used, incomplete, or not in its original condition, a 30% restocking fee may apply. Direct exchanges are not offered. To exchange an item, please purchase the replacement separately and return the original for a refund.

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We act solely as a reseller. Any product warranty is provided and administered by the manufacturer, not by our store. That means eligibility, coverage, and outcomes are determined by the manufacturer’s policy for each brand and model. Before purchasing, we recommend reviewing the warranty terms on the manufacturer’s website or in the product documentation to confirm what is covered and for how long.

If you need warranty service, please file the claim directly with the manufacturer. They may require proof of purchase, the product serial number, original packaging, photos, or basic troubleshooting. Some brands ask you to register the product or obtain a case number before shipping it for repair or replacement. We don’t submit or approve claims, but we can point you to the correct support links and contact details.

Keep your invoice and packaging in a safe place, and report any functional issues to the manufacturer as soon as they appear. If you’re unsure whether a problem is covered, the manufacturer’s support team can confirm next steps and timelines. While we cannot intervene in decisions or outcomes, we’re happy to provide purchase documentation or guidance so you can move through the warranty process smoothly.

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