5 Reasons To Use a Modbus Data Acquisition System

Whether you monitor environmental conditions, manage a process, or keep track of equipment performance, a Modbus Data Acquisition system can provide valuable insights.
Use these five reasons to use a Modbus Data Acquisition System to make informed decisions about your data collection needs.

One of the most common applications for Modbus Data Acquisition systems is measuring process variables and sending the information to a centralized point. These variables can be processed and sent back for corrective action.
Two wires retrieve the process variables, and the same wires can work for corrective action. Also, one field instrument could have many process variable inputs, such as eight 4-20mA inputs, flow, and temperature. A process controller could also have a process variable, a remote setpoint, and a corrective action. All this information travels on a pair of wires.

A Modbus Controller can log information from Modbus Systems and, with local function blocks, can read internal and external registers. A local USB drive or SD Ram card can store internal or external register information.
Information can also log SCADA packages, where charts can display many process variables.

Many process control instruments now use Modbus RTU. Pressure transmitters, gas analyzers, flowmeters, and density meters all use a Modbus RTU RS485 output.
Modbus function blocks can read decimal integers or a 32-bit floating-point. It can still read whether the lower word is first or second. It is now possible to capture the register that shows the digital value and convert it to an analog signal.
Once the read function block obtains the register, the scale function block converts it to a scaled number, and the write function block provides a 4-20mA output. The only function blocks needed are a holding register, or a read input register, and a scale function block in one single Modbus Controller.

It is possible to control process loops with Modbus, and it can be as simple as having one Modbus analog input card and sending the same signal to a Modbus output card. You can do this with or without a Modbus Master Controller.
Modbus Controllers can act as Modbus Masters or Modbus Slaves. Some Modbus Controllers have analog inputs, analog outputs, digital inputs, and digital outputs. Some Modbus Masters have Thermocouples, RTD, 4-20mA, or Voltage Inputs.

Although the task of Modbus is to provide information to PLCs or SCADA systems, sometimes local information is necessary. With the aid of Remote Modbus Displays, the plant operator visually sees process variables in remote places.
This operator is a low-cost solution to displaying process variables. These variables can display in precise engineering units, and the display could be a Slave or Master.