Modbus Master

A Modbus master is the device within a Modbus communications network that requests information from other devices.

Modbus is a way of communicating information between electronic devices on a network. It is generally used by a data gathering system to collect signal transmissions from instrumentation and control devices.

Modbus Operates Under Master/Slave Model
Modbus is a master/slave protocol. This means that a single Modbus master will control all of the other devices on a network.

A Modbus master can request information from up to 247 other electronic devices, which are known as slaves along the network. A Modbus master will request information from these devices across a serial connection, either RS-485 or RS-232. The Modbus master can also write information to the slave devices using the same serial connection.

Bits are Sent to the Modbus Master in the Form of Voltages
Data is sent from slave devices to the Modbus master serially. These communications take the form of bits, or strings of ones and zeros. These bits are sent as voltages, with a zero being a positive, and a one being a negative voltage. Since these long strings of bits can be difficult to read, they are repacked into the hexadecimal form, packaging 4 bits together.

Each slave device is assigned a function code. Before it transmits communications to the Modbus master, it will identify itself to the Modbus master using a unique function code. This identifies which of the networked slave devices the data is coming from. Following the function code transmission, the slave device will communicate its full message to the Modbus master.

An Advanced Modbus Master Can Support Your Other Protocols
An advanced Modbus master can be used for more than simply communicating with Modbus slave devices. When seeking a master for your Modbus network and other devices, you should look for a master than can bring your Modbus alarms and notifications from your other protocol devices into one master screen. This will help you monitor your network as efficiently as possible, eliminating the need for multiple operators and workstations to accomplish your network alarm monitoring.

T/Mon NOC is an Advanced Modbus Master that Saves Your Company Money
The T/Mon NOC is one such Modbus master that can greatly increase your organization's visibility while reducing your monitoring costs. With an ordinary Modbus master, you will be unable to collect alarms from your non-Modbus devices. This will require you to deploy multiple masters to support all of the different protocols within your network, and hire additional operators to monitor the communications from these assorted masters.

ith T/Mon NOC, you can have Modbus alarms and alarms from over twenty-five additional protocols forwarded into one master browser. This convenient, single-window view allows you to monitor your entire network of devices through a single workstation, using a single operator.

T/Mon NOC Modbus Master Sends You Page and Email Alarm Notifications, No Matter Where You Are
Another advanced feature of the T/Mon NOC Modbus master is the page and email alarm notifications utilized by the system. Anytime an alarm occurs within your network, your Modbus master will send a page or email directly to your network technician. These pages can even be directed to specific technicians according to your technical staff's schedule, and their individual skill sets. With these advanced features, you'll be the first to know anytime a slave device has lost communication with your Modbus master.

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T/Mon NOC

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