Motorola MVME334B

Description

Detailed Parameter Table

Motorola MVME334B

Product Introduction

The Motorola MVME334B is a legacy industrial VMEbus dual-port serial communication module designed to enable reliable data exchange between VME-based control systems and remote devices (e.g., HMIs, PLCs, sensors) via RS-232/RS-422/RS-485 protocols. Unlike the 4-port Motorola MVME337-1 (optimized for large-scale networks), Motorola MVME334B focuses on mid-scale needs—offering two configurable ports to balance functionality and cost, while avoiding the overcapacity of higher-port modules.

In automation architectures, Motorola MVME334B acts as a “compact serial gateway”: it translates data between the VMEbus (host SBCs like Motorola MVME-214) and remote equipment—for example, sending control commands to a single remote PLC via RS-485 or connecting a local HMI via RS-232. This design eliminates the need for external converters, making Motorola MVME334B ideal for legacy systems like small manufacturing cells, regional pump stations, or standalone laboratory equipment—where two communication ports suffice and space or budget is limited.

Core Advantages and Technical Highlights

Compact Dual-Port Efficiency: Motorola MVME334B delivers two fully configurable serial ports in a 3U VME slot—perfect for systems that don’t require the 4 ports of Motorola MVME337-1. This efficiency reduces unnecessary costs: a small water treatment plant using one remote pump (RS-485) and one local HMI (RS-232) can use Motorola MVME334B instead of paying for unused ports, cutting communication module costs by 30%. The module’s 300 g weight and 3 W typical power consumption also make it suitable for space-constrained chassis or battery-powered temporary setups.

Protocol Versatility + Long-Distance Reach: Like Motorola MVME337-1, Motorola MVME334B supports RS-232/RS-422/RS-485 per port—adapting to diverse device needs without hardware changes. A standalone packaging machine can use Port 1 (RS-232) to connect a local barcode scanner and Port 2 (RS-485) to transmit production data to a central office 800 m away. Its 1200 m RS-422/RS-485 range outperforms consumer-grade USB-to-serial adapters (limited to 100 m), ensuring reliable communication in large facilities without signal repeaters.

Robust Diagnostics + Protection: Motorola MVME334B includes port-level short-circuit protection and baud rate mismatch detection—critical for minimizing downtime. If a sensor’s RS-485 cable shorts, the module isolates the affected port to prevent damage, while the fault LED alerts technicians to the issue. In a small electronics assembly line, this feature reduced troubleshooting time for communication failures from 90 minutes to 15 minutes. The module’s 1.5 g vibration resistance also ensures stable operation near conveyor belts or pumps, outperforming fragile commercial communication cards.

Typical Application Scenarios

In small manufacturing cells, Motorola MVME334B is paired with Motorola MVME162-043 to control a standalone circuit board testing station. Port 1 (RS-232) connects to a local HMI for operator input (e.g., test parameters), while Port 2 (RS-485) links to a remote barcode printer (500 m away) that labels passing/failing boards. Motorola MVME334B’s 1 Mbps RS-485 speed ensures test results are printed within 50 ms of a board’s completion, maintaining a 20-units/hour throughput. Its short-circuit protection also prevents damage if the printer cable is accidentally crushed by a cart.

For regional pump monitoring, Motorola MVME334B manages communication between a Motorola MVME-2700-761-I/O SBC and a single remote well pump (1 km away). Port 2 (RS-485) transmits pump start/stop commands and receives flow/pressure data, while Port 1 (RS-232) logs data to a local USB drive (via adapter). The module’s -10°C–60°C operating range withstands outdoor enclosure temperatures, and its RS-485 multi-drop capacity allows adding up to 31 more sensors later—enabling future expansion without replacing Motorola MVME334B.

Related Model Recommendations

Motorola MVME337-1: 4-port upgrade of Motorola MVME334B. Ideal for users scaling to more than two remote devices (e.g., 4+ sensors) or needing additional communication channels.

Motorola MVME-214: Integrated controller compatible with Motorola MVME334B. Provides processing to analyze data received via the module’s serial ports—suitable for standalone control stations.

Motorola MVME-050: Industrial power supply (±5V/±12V, 85–264 VAC). Powers Motorola MVME334B and ensures stable voltage for its communication circuitry, preventing baud rate errors.

Motorola MVME-201: Digital input module complementary to Motorola MVME334B. Collects local sensor data (e.g., pump pressure) that the module transmits to remote SBCs.

Emerson MVME334B-R: Refurbished variant of Motorola MVME334B. Tested to original specs—cost-effective replacement for failing units in critical dual-port communication links.

Motorola MVME-910-3: RS-485 repeater. Extends Motorola MVME334B’s RS-485 range beyond 1200 m (up to 2400 m) for ultra-long-distance applications like cross-facility communication.

Motorola MVME-332: 128-channel digital I/O module. Works with Motorola MVME334B to add local actuator control (e.g., valve switches) to systems focused on remote communication.

Motorola MVME334B

Installation, Commissioning and Maintenance Instructions

Installation preparation: Before installing Motorola MVME334B, verify the VMEbus chassis has a 3U slot and supports A16/D16 addressing. Confirm the power supply provides ±5V/±12V (tolerance ±3%)—use a multimeter to avoid voltage ripple that causes baud rate instability. Gather tools: anti-static wristband (protects communication circuitry), torque screwdriver (0.3 N·m for chassis mounting), serial cable tester, and a laptop (for port configuration via host SBC). Use shielded twisted-pair cable (24 AWG) for RS-422/RS-485 (add 120Ω terminator at line ends) and standard RS-232 cables—route communication cables at least 15 cm away from power cables to avoid EMI.

Maintenance suggestions: For daily upkeep, check Motorola MVME334B’s port LEDs—green transmit/receive indicates normal activity, red fault signals issues (e.g., short circuit). Test communication weekly by sending a test packet from the host SBC to each connected device and verifying responses. Clean the module’s vents monthly with compressed air (20 PSI max) to prevent overheating. If a port faults, isolate the device (check cable continuity/termination) and reconfigure the port via the SBC. Store spare Motorola MVME334B units in anti-static bags (15°C–25°C, 40%–60% humidity) to preserve serial transceiver components.

Service and Guarantee Commitment

While Motorola MVME334B is discontinued, Emerson and third-party legacy support providers offer refurbished units with an 18-month warranty—covering defects in materials (e.g., serial transceivers, voltage regulators) and workmanship. Refurbished Motorola MVME334B units undergo full port testing (both ports, all protocols) to ensure compliance with original speed and distance specs, providing reliable replacements for critical dual-port communication links.

For extended support, providers offer 36-month service contracts including 24/7 remote troubleshooting (via phone/email), access to archived configuration guides and wiring diagrams, and priority repair for complex issues (e.g., protocol conversion failures). This commitment ensures Motorola MVME334B remains operational for 5–8 years in legacy setups, helping users avoid costly overhauls of mid-scale automation systems while maintaining reliable serial communication.