Modbus RTU I/O Modules

Modbus RTU I/O Modules

Acromag’s BusWorks 900MB Series is a high-performance collection of analogue and discrete I/O modules with Modbus-RTU network communication. These units feature universal input/output ranges and an intelligent microcontroller to provide extreme flexibility and powerful monitoring and control capabilities. BusWorks modules are ideal for a wide variety of distributed I/O applications. Including data acquisition, control, process monitoring, and test & measurement.

To ensure unsurpassed performance, these I/O modules employ the latest digital technology. State-of-the-art flash microcontrollers. Plus optically isolated input, output, power, and network circuits to increase noise/transient immunity and prevent ground loops. Status LEDs provide diagnostic feedback and visually indicate which channels are outside their calibrated range.

Sophisticated watchdog timer functions allow the application to define the module’s fail safe output state. The watchdog timer invokes the failsafe condition. This is when communication between the host and module exceed a duration specified by the application. For further security, a second hardware watchdog timer monitors the microcontroller for failed operations or a “lock-up” condition and automatically resets the unit.

Select from a variety of Analogue or Discrete I/O Models to meet your application requirements.

More specific model information on the Modbus RTU Analogue & Digital I/O is further down the page.

For further information, contact us.

Modbus RTU Analogue I/O	Modbus RTU Digital I/O	RS-485 Repeater Modbus RTU
Multi-channel units with flexible I/O ranges provide an isolated network interface for voltage, current, and temperature sensor signals or for non-networked controller signals. High-resolution, low noise, A/D converters deliver high accuracy and reliability.	Monitor 12 signals per unit with digital input models. These units provide an isolated network interface for discrete logic-level devices with active-high or low inputs. Inputs monitor on/off, high/low, or open/close status of motors, pumps, valves, heaters, fans, and other industrial equipment	Acromag’s RS-485 network repeater device allows users to take full advantage of the RS-485 standard’s extended communication distances and multi-dropping capabilities
Modbus RTU Software Support	Modbus RTU Accessories
For fast and easy implementation, Acromag offers a variety of utilities and controls to speed development with OPC, Visual Basic, Visual C, and .NET environments.	Select from an assortment of power supplies, adapters, cables, and mounting kits to simplify installation.

Modbus RTU Analogue I/O Modules

Analogue Input Highlights

• Universal I/O ranges support a variety of devices
• Differential inputs eliminate ground loops
• Discrete outputs enable local limit alarms or host-controlled on/off switching
• Modbus-RTU high-speed RS-485 communication

Control up to 4 devices with a single unit with 900MB output modules. These units provide an isolated network interface for analogue output signals. Outputs can be used to control mechanical equipment or write to display devices, data loggers and recorders, or to transmit data to non-networked PLCs and controllers.

Analogue Output Highlights

• Universal I/O ranges support a variety of devices
• Discrete outputs enable local limit alarms or host-controlled on/off switching
• Modbus-RTU high-speed RS-485 communication

Modbus devices communicate using a master-slave technique in which only one device (the master) can initiate transactions (called queries). The other devices (slaves) respond by supplying the requested data to the master, or by taking the action requested in the query. A slave is any peripheral device (I/O transducer, valve, network drive, or other measuring device) which processes information and sends its output to the master using Modbus. Acromag Series 900MB I/O Modules are slave devices, while a typical master device is a host computer running appropriate application software.

DC Current / Voltage Modbus RTU Input Module with Limit Alarms Models: 913MB / 914MB	DC Current / Voltage Modbus RTU Output Modules with Discrete Outputs Models: 917MB / 918MB	Thermocouple / Millivolt Modbus RTU Input Module with Limit Alarms Model 924MB
913MB: 4 current input channels 914MB: 4 voltage input channels 4 input channels 0 to 20mA DC (0 to 20A AC with AC sensor) or ±10V DC input range 4 alarm channels, open drain MOSFETS (1A DC loads, 0 to 35V DC) 10 to 36V DC, 24V AC power Modbus RTU high-speed RS-485	917MB: Modbus RTU DC Current Output Module 918MB: Modbus RTU DC Voltage Output Module 4 analogue output channels 0 to 20mA or 0 to 10V DC output range 4 discrete output channels, open drain MOSFETS (1A DC loads, 0 to 35V DC) 10 to 36V DC, 24V AC power Modbus RTU high-speed RS-485	4 input channels, thermocouple (types J, K, T, R, S, E, B, N) or millivolt (±100mV DC) input 4 alarm channels, open drain MOSFETS (1A DC loads, 0 to 35V DC) 10 to 36V DC, 24V AC power Modbus RTU high speed RS-485
RTD / Resistance Modbus RTU Input Modules with Limit Alarms or Discrete Outputs Models: 932MB / 934MB	Frequency / Pulse Counter Modbus RTU Input Modules with Periodic or Pulse Waveform Input Model: 942MB
932MB: Modbus RTU RTD/Resistance input module: 2 input channels 934MB: Modbus RTU RTD/Resistance input module: 4 input channels 2 or 4 input channels, RTD (100 ohm Pt, 120 ohm Ni, 10 ohm Cu) or resistance (0 to 500 ohms) input Solid-state relays discrete output, Form A, SPST-NO 10 to 36V DC, 24V AC power Modbus-RTU high-speed RS-485	2 input channels, 0 to 50KHz in 3 selectable ranges: Amplitudes up to 140V AC peak Amplitudes up to 200V peak Pulse counter range of 0 to 65535 Solid-state discrete output relays (1A DC loads), 0 to 48V DC 10 to 36V DC, 24V AC power Modbus-RTU high-speed RS-485

Modbus RTU Digital I/O Modules

Discrete Input Features

♦ 12 I/O channels in a single inch-wide unit reduces system costs and saves panel space
♦ Built-in pull-up/pull-down resistors simplify wiring and lower system costs

Control 12 devices from one unit with digital output models. These units provide an isolated network interface to control discrete logic-level devices with high or low-side switching. Outputs control on/off, high/low, or open/close status of motors, pumps, valves, heaters, fans, and other industrial equipment.

Discrete Output Features

♦ Bi-directional I/O provides level control and status verification in one unit
♦ Watchdog timers provide a configurable failsafe output state for use when host I/O communication is lost

Multi-Channel Modbus-RTU Discrete I/O Modules Models: 901MB / 902MB / 903MB	Multi-Channel Modbus-RTU Discrete I/O Modules Models: 904MB, 905MB, 906MB
901MB: Discrete Input Module: 12 Input Channels 902MB: Discrete Output Module: 12 Output Channels 903MB: Discrete Input / Output Module: 12 Input and 12 Output Channels Active-Low Inputs, Sinking Outputs (Low-Side Switching) 12 input and/or 12 output channels 0 to 35V DC I/O range 10 to 36V DC, 24V AC power High-speed RS-485	904MB: Discrete Input Module: 12 Input Channels 905MB: Discrete Output Module: 12 Output Channels 906MB: Discrete Input / Output Module: 12 Input and 12 Output Channels Active-High Inputs, Sourcing Outputs (High-Side Switching) 12 input and/or 12 output channels 0 to 35V DC I/O range 10 to 36V DC, 24V AC power High-speed RS-485