Black Box ME800A-R4

Overview

The Black Box ME800A-R4 is an asynchronous RS232 extender designed to transmit serial signals over CATx cabling, extending communication distances up to four miles while supporting data rates up to 115.2 kbps. It enables full duplex communication on a four-wire link, making it ideal for environments where legacy RS232 devices need to connect over long distances without signal degradation.

This extender is well suited for industrial control rooms, security systems, building automation, and other settings where RS232 devices are located far from controllers or computers. Its design protects against electrical noise and ground loops, ensuring reliable data transmission even in challenging environments.

Key features

• Extends RS232 signals over standard CATx cabling, allowing long-distance connections without specialized cables
• Supports full duplex communication to maintain simultaneous two-way data flow
• Built-in transformer and optical isolation provide protection from electrical interference and ground loops
• Flip-top lid allows quick switching between DTE and DCE modes to match device pinouts without guesswork
• Front-panel loopback test button enables easy verification of continuity and polarity before deployment
• Compatible with common RS232, DB9, and RJ-11 connectors through standard adapters for flexible integration
• Compact form factor fits easily into racks or wall-mount enclosures without requiring system redesign

Key specs

• Data rate: up to 115.2 kbps
• Maximum distance: up to four miles over CATx cable
• Communication: asynchronous RS232, full duplex
• Connection type: DB9 female to removable terminal block for four-wire CATx
• Isolation: transformer and optical isolation for noise and ground loop protection
• Mode selection: flip-top lid for DTE/DCE switching

Connectivity and compatibility

The ME800A-R4 connects to standard RS232 devices via a DB9 female connector, while the remote end interfaces with CATx cabling through a removable terminal block. This setup allows easy integration with existing RS232 equipment and network-grade cabling infrastructure. The unit supports common adapters for RJ-11 and other RS232 connectors, making it versatile for various legacy devices.

Its compatibility with standard cabling and connectors means it can be deployed without extensive rewiring or specialized hardware, fitting well into existing control rooms, security racks, or automation closets.

Installation and setup

Installation is straightforward, requiring only a pair of ME800A-R4 units—one near the host device and one near the remote equipment. The flip-top lid simplifies configuration by allowing quick selection between DTE and DCE modes, eliminating common wiring errors. The front-panel loopback test button helps technicians verify the connection before full operation, reducing troubleshooting time.

This ease of setup makes it practical for field technicians and engineers who need to extend RS232 signals reliably without complex configuration or downtime.

Ideal uses and environments

This extender is a strong choice for industrial and commercial environments where RS232 devices remain in use but require longer cable runs than typical RS232 limits allow. It works well in factory floors, security installations, building automation systems, and remote monitoring setups. Users who need to maintain legacy serial equipment while leveraging cost-effective CATx cabling will find this unit particularly valuable.

Its robust noise protection and flexible connectivity make it suitable for electrically noisy environments and installations where equipment placement is constrained by cabling rather than device location.

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, with tags, manuals, accessories, and original, unaltered packaging. Any item kept will be deducted from the refund. Start a return by sending us an email. Items sent back without approval may be refused or returned to the sender.

Some items are not returnable: opened TVs/combos/monitors 37″+, 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; allow 5–7 business days for the credit to post. Shipping, handling, customs duties, and import taxes are nonrefundable. If an item is used, incomplete, or not in original condition, a 30% restocking fee may apply. Direct exchanges are not offered; purchase the replacement and return the original for a refund.

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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