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MAQ20 Communication Modules

Provide Connection, Power, Interface

MAQ20 Communication Modules image

The MAQ20 communication module is offered in two models and provides the connection between a host computer and a MAQ®20 Data Acquisition System. MAQ20-COM4 communicates using Ethernet, USB, or RS-485; MAQ20-COM2 uses Ethernet, USB, or RS-232. Ethernet communications use the Modbus TCP protocol and USB communications are based on the Modbus RTU protocol, which RS-485 and RS-232 communications also use. Serial communications over RS-485 can be either 2-wire or 4-wire.

When using the Ethernet interface, up to four simultaneous socket connections are supported and each socket can process up to four simultaneous Modbus TCP transactions. Serial communications over RS-232 or RS-485 can be run at baud rates as fast as 921.6 kbps.

A very useful feature of the MAQ20 system is the capability to store acquired data locally for later analysis. This is provided by the easily accessible and removable 4GB micro-SD memory card that is in the MAQ20-COMx module and can be used to log data acquired from all input modules.

Each MAQ20-COMx module can interface to up to 24 I/O modules in any combination, allowing high channel counts and great flexibility in system configuration.

To power the system, a 7-34 VDC power source is connected to the communication module. Regulated and protected supplies within the module then provide power both to the internal circuits and to all I/O modules in the system. When many high power I/O modules are used in a system, MAQ20-PWR3 load-sharing boost power supply modules can be installed in standard I/O module slots to provide the necessary additional power.

To ensure robustness, the communications interface-to-bus isolation is 50 VDC and power input terminals are protected against overvoltage, transient, and reverse connections.

As a minimum, a MAQ®20 Data Acquisition System must have a communication module, a backbone, and one I/O module.

Circuit diagram Dataforth MAQ20 Communication Modules

Block Diagram MAQ20 Communication Modules

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  • Connect Host Computer and MAQ®20 System
  • Communicate using Ethernet, USB, RS-485, RS-232
  • Up to 4 Simultaneous Socket Connect. with Ethernet
  • Baud Rates to 921.6 kbps with RS-232 / RS-485
  • Follow Modbus TCP or RTU Protocols
  • Store Acquired Data Locally
  • Interface to up to 24 I/O Modules
  • 50 VDC Communications Interface-to-Bus Isolation
  • Operating Temperature -40 °C to +85 °C
  • Dimensions 114.6 x 28.2 x 82.8 mm
  • DIN Mount
  • Heavy Industrial CE, ATEX Pending
  • UL/CUL Class I, Division 2, Gr. A, B, C, D Pending