M - Metasys - LIT-1201612 - General System Information - Metasys System - 12.0

Metasys System Glossary

Product name
Metasys System
Document type
Technical Bulletin
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Mobile Access Portal gateway. A pocket-sized web server that provides a wireless mobile user interface to Metasys equipment controllers, FX equipment controllers, CH equipment controllers, TEC3000 Series thermostats, and Smart Equipment Rooftop Units (RTUs). The mobile user interface can be displayed in the browser of a phone, tablet, or computer.


Also known as Meter Bus, M-Bus is a European standard (EN 13757-2) for remote reading of gas and electricity meters. M-Bus is designed for communication on two wires.


Mass Changes Tool. A software tool you can use to edit the System Configuration Tool (SCT) database and export files. The MCT also generates IMP files for the SCT and Metasys engines.

Mesh Coordinator

The Mesh Coordinator is a router that connects to the Wireless Router Gateway (WRG).

Metasys API

Use the Metasys Application Programming Interface (API) to read, write, and command one or more Metasys objects and properties to provide a secure way to bi-directionally integrate with third-party applications. Data is securely extracted from the Metasys system and integrated with third-party data visualization tools to meet robust data analysis and reporting needs.

Metasys Database Manager

Software tool that helps to manage and monitor Metasys system databases on a Metasys server. This optional application adds a database icon to the computer's task bar. The color of the icon indicates the current state of the monitored databases.

Metasys Monitoring and Commanding API

Use the REST-compliant Metasys Monitoring and Commanding Application Programming Interface (API) to read, write, and command one or more Metasys objects and properties, including Present Value. This API succeeds the Metasys System Secure Data Access dynamic link library (MSSDA DLL).

Metasys Server

Device on the Metasys network that runs ADS/ADX/OAS software.

Metasys UI

A software application that is installed when you install the software for any Metasys server (ADS, ADS-Lite, ADX, or OAS) or server-based engines (NAE85 or LCS85). The Metasys UI provides a simple location-based navigation approach to finding information, including the ability to search for any location by name and to bookmark a location in the browser. All data displayed in the Metasys UI is organized in a dashboard format, presenting to you the complete story of what is happening within a space, equipment, or central plant. You can access the Metasys UI from any type of client device with any screen size. Use Metasys UI for any building system operation.

Metasys UI Offline

See Johnson Controls System Configuration Tool (JCT).


Metasys Export Utility (MEU). The Export Utility extracts historical trend, alarm, and audit data from the system and presents the historical data in a variety of formats. Using these flexible formats, in programs such as Microsoft® Excel® and Access®, you can easily sort, compare, and archive data in spreadsheets and databases.


A communication protocol developed by Modicon systems. The protocol transmits information between electronic devices over serial lines.

Modbus Gateway

A communication device for the BCPro system that provides integration of third-party Modbus equipment into the BCM system for monitoring and controlling a wide variety of HVAC equipment, meters, fire alarm panels, and lighting. You can configure the gateway for the Modbus IP or Modbus RTU application protocol.

MQ Telemetry Transport (MQTT)

MQTT is a lightweight, publish-subscribe type network protocol that transports messages between IP devices and applications.

MQTT Broker

An MQTT Broker is an intermediary that enables MQTT clients to communicate. An MQTT broker receives messages published by clients, filters the messages by topic, and distributes them to subscribers.


A communications bus protocol based on BACnet standard protocol SSPC-135, Clause 9. The MS/TP bus connects the various components on both the SA and FC Buses. Media choices for MS/TP Bus communication include three-wire twisted cable and four-wire twisted cable; solid or stranded; shielded or unshielded. The MS/TP Bus superseded the N2 Bus.


Metasys System Secure Data Access dynamic link library (DLL). A now obsolete technology that offered secure access to information in the Metasys network. Using web methods, this DLL allowed you to build custom applications with programs like Microsoft® Visual Basic® to retrieve and update object attribute information in your building network.


Metasys for Validated Environments, extended architecture. MVE is an enhanced feature of the Metasys system for facilities that require regulatory compliance for their environmental systems. It includes the capability to configure electronic signatures with required annotations for user interactions with the system. MVE is specifically designed to help customers address U.S. Food and Drug Administration (FDA) electronic records and signature requirements (Title 21 Code of Federal Regulation [CFR] Part 11). MVE requires an ADX with other specific prerequisite software.

MVE Required Annotation

A note that the user must enter when applying an electronic signature. Required annotations, available on MVE systems only, are different from standard annotations, which are available on any Metasys system. Examples of required annotations include Normal Process Adjustment and Scheduled Maintenance.

MVE Signature Reason

A meaning associated with the signature that the user must enter when executing an electronic signature. Signature reasons exist on MVE systems only. Examples of signature reasons include Review, Approve, Operator Action, and Author.