IntelliLogger Modbus Capability
With the suite of new Modbus Options, the IntelliLogger can now be utilized in Modbus network applications. A Modbus RTU Master enabled IntelliLogger can read Modbus register parameters from a connected Modbus Slave device (e.g. a flow computer, transducer, etc) along with other conventional hardwired inputs (e.g. thermocouples, pressure transducers, etc). These sampled values can then be processed, reported, stored to memory, embedded into emails, FTP’d and/or served up in Web pages… all by the IntelliLogger.
Alternatively, the IntelliLogger can be configured as a Modbus RTU Slave (or Modbus TCP Server) and share its own internal Modbus registers for interrogation or update from other networked Modbus Master (Client) devices.
A Modbus educational overview as well as further details about the IntelliLogger Modbus feature are described below.
Modbus Interface with the IntelliLogger™
The IntelliLogger can be integrated into a Modbus network providing a whole new set of data collection and reporting capabilities. With the new Modbus interface options, the IntelliLogger can be quickly programmed to perform functions such as:
- Query connected Modbus ‘smart’ transducers for Register values and utilize them in the IntelliLogger Program Net simultaneously with other hardwired inputs.
- Expose internal registers to other Modbus devices for use in their algorithms. Shared IntelliLogger Registers can be input, output and/or calculated values.
- Remotely control IntelliLogger outputs via Modbus communications from a Modbus Master
- Serve Web pages with embedded data collected from Modbus Slave devices
- Adjust IntelliLogger operation via Modbus communications during IntelliLogger program execution
- Send status and/or alarm emails (or SMS) with embedded readings and/or attached data collected from Modbus Slave devices
- Acknowledge IntelliLogger programmed alarms
- Change IntelliLogger alarm thresholds during IntelliLogger program execution
- FTP readings collected from Modbus Slave devices as well as hardwired inputs
The IntelliLogger can now be ordered with the following Modbus support options:
MODBUS RTU MASTER
MODBUS RTU SLAVE
MODBUS TCP SERVER
Modbus RTU Master Option
IntelliLoggers equipped with the Modbus RTU Master option can read (and optionally write) register values from (to) other Modbus networked Slave devices. 1000’s of Modbus slave devices are manufactured by various companies ranging from flow computers to ‘smart’ transducers to power meters, displays, controllers, and much more… all of which can now be interrogated by the IntelliLogger with the new Modbus Master option.
Programming the IntelliLogger as a Modbus RTU Master
In the Modbus RTU Master mode, the IntelliLogger is programmed using the powerful and intuitive icon-based programming capability provided by HyperWare-II . A Program Net is built which can query the connected Modbus Slave device internal registers through the addition of an icon representing that register… much like the method used for logging conventional hardwired input and output signals.
A Modbus RTU Slave Device icon is added for each of the Slave device registers that the IntelliLogger will access. The values retrieved from the Slave device can then be used in further processing within the Program Net just like other analog or digital inputs that have been hardwired to the IntelliLogger (e.g. thermocouples, RTD’s, 4-20mA, voltages, etc). The values can be scaled, averaged, used in calculations, used in alarms and more.
Additionally, many Modbus Slave devices may have writable Registers… allowing the IntelliLogger to change settings within the Slave device by writing new values into these writable registers. Write functionality may be used for changing alarm thresholds, changing output states, adjusting operational constants, branching of algorithms, input scaling values within the device, etc.
Modbus Slave icons are configured similarly to all HyperWare-II Program Net icons… through the Icon Configuration dialog. Within the Modbus Slave icon configuration dialog settings such as device address, Register address and data format are specified. The icon supports 16 and 32 bit integer, 32 bit floating point and even 16 bit ‘bitfield’ register types. Once the icon for a particular Slave device Register is made, it can be saved/opened from a growing library of Modbus icons for quick future use.
Modbus RTU Slave Option
IntelliLoggers equipped with this option and connected to a Modbus network can be programmed to expose internal Register values representing the different parameters to connected Modbus Master devices (e.g. controllers, displays, etc). With this feature, the IntelliLogger can be sampling temperatures, pressures, flows, etc from hardwired inputs… performing calculations and also serving the Register values to a connected Master device over the Modbus RTU network.
Configuration of the Registers is simply done from within the HyperWare-II icon-based programming environment. Register addresses are assigned to each of the icons within the Program Net for which register value sharing with a connected Modbus Master device is desired.
IntelliLogger Modbus Registers can be configured to allow a Master device to access the following IntelliLogger parameters:
Current Value Readings
Current values, whether they be analog input signals, calculated values, event states or any other I/O parameter can be read from the IntelliLogger. Modbus access is implemented by the addition of Probe Point icons into the IntelliLogger Program Net and then assignment of a Modbus register number to the Probe Point.
Remote Contol Icon State Update
Remote Control (On/Off) icon states within the IntelliLogger Program Net can be updated by writing to IntelliLogger Modbus Registers . This facilitates remote On/Off control of actions within the IntelliLogger from a remote instrument over the Modbus link. These On/Off actions can change the operation of the IntelliLogger program while it is running as well as control physical outputs on the IntelliLogger.
Remote Constant Update
Upon command from a Modbus Master device, the Remote Constant icon within an IntelliLogger Program Net can be updated. This allows a remote Modbus Master device to change set-points, alarms, constants used in calculations, etc via the Modbus link.
Modbus TCP Server
This option functions identically to the Modbus RTU Slave option (above) with the exception that communications are all performed over Ethernet using the Ethernet port of the IntelliLogger. With the Modbus TCP Server option, Current Values as well as Remote Control and Remote Constant settings can be read and updated by a Modbus TCP Master on the LAN… or even over the Internet!
IntelliLogger™ Communication Ports
The IntelliLogger has an integral Ethernet Port for LAN connectivity and Modbus TCP communications. Modbus RTU communications with other Modbus devices is via one of the integral RS-232 ports directly (for RS-232 capable Modbus devices) or more commonly via the Logic Beach
SCC-1, RS-232 to RS-485 converter… allowing for connection to one or more RS-485 multi-dropped Modbus devices.