Automated Logic MEX816U Expander Control Module

Automated Logic MEX816U Expander Control Module

Automated Logic MEX816U Expander Control Module The Automated Logic MEX816U Expander Control Module is a high-performance ruggedly manufactured I/O expansion unit designed to easily scale your ME-line multi-equipment automation systems. Designed for demanding commercial, industrial and maritime building management systems (BMS), the MEX816U brings high density monitoring and control by adding 16 universal inputs and 8 universal outputs via a high speed Xnet I/O expander bus.

Configured to control complicated central plant machinery, maritime HVAC ducting or auxiliary plant systems, this expander module provides accurate data acquisition and robust output execution in high-stress environments. This is the industry standard solution for maximum system architectural efficiency. It is constructed with a heavy duty aluminum cover for enhanced noise immunity and electrical protection.

Model Details

• Brand: Automated Logic Corporation (ALC)
• Model Number: MEX816U / MEx816u
• MPN (Manufacturer Part Number): MEX816U
• Product Type: I/O Expander Module (ME-Line Series)

Technical Specifications: MEX816U

Features

• High Density I/O Scaling System capacity is scaled up to 16 ultra-precise 14-bit inputs and 8 adaptable 12-bit outputs in a single small footprint.
• Xnet High-Speed Communication: Operates on a dedicated 500 Kbps Xnet I/O bus, enabling daisy-chaining to a maximum of 100 feet from the master ME controller.
• Built in Integrated Local Override Switches: Hand/Off/Auto (HOA) switches and potentiometers provide important manual override control for testing or emergency overrides.
• Industrial Grade Noise Protection: Heavy electromagnetic interference (EMI) is shielded from the internal electronics by a sturdy aluminum enclosure.

Applications

1. Multi-Equipment HVAC Automation: Major mechanical AHUs, VAV Loops and complicated dampers.
2. Marine & Industrial Chillers: Real time monitoring of thermal fluid loops, compressor relays and temperature thermistor sensors raw.
3. Boiler Plant Integration: Universal analog outputs control secondary pumping, burner staging and sequence flow networks.
4. Environmental Conditioning: Marine machinery space ventilation, offshore accommodation deck pressure zones and vessel cargo hold cooling controls.

System Compatibility

• Primary Controllers: Integrates directly with Automated Logic ME812u master controllers and standard WebCTRL system interfaces.
• Legacy Systems: Backward compatible with select Mx-series I/O expanders utilizing specialized 9-pin Sub-D connection setups.
• Programming Software: Fully addressable and configurable via WebCTRL’s GEO tree I/O points tab and EIKON LogicBuilder software platforms.

Part Number Cross-References

• ALC-MEX816U
• MEx816u Rev. 2011
• Carrier CSMEXrev3

Professional Integration Guide:

1. Prevent Ground Loops: If you are running loop-powered 4-20 mA sensors, utilize the onboard Aux Power Out connector (+24 VDC, 200 mA max). Wire the positive lead of the sensor directly to the Aux terminal and return the negative lead to your designated input (+) terminal. This guarantees clean signal readings across the 14-bit A/D converter.
2. Jumper Verification: Never apply 24 VAC power to the Universal Outputs (UO). Always set your output jumpers before powering up the module. Incorrect jumper positions on an active analog control loop run the risk of frying downstream actuators or safety interlocks.
3. Daisy-Chain Topology: When configuring multiple MEX816U expanders on the Xnet bus, ensure they are wired in a true daisy-chain structure. Avoid star topologies, as they degrade the 500 Kbps data transfer rate and introduce parsing noise into the WebCTRL interface. Use the rotary dip switches to establish clear, distinct hardware addresses before commissioning the logic loops in EIKON.