EasyIO FG32+ and EDMI MK7C with SBS Modbus Duo adapter and Moxa nPort
We have received the new EasyIO FG32+ and rapidly had it connected to an EDMI MK7C electricity utility meter on our lab test bench.
Our first impressions are that the unit is ruggedly built with a quality thick ABS plastic enclosure. All terminals are Phoenix style which allow for easy disconnection or replacement of the unit. We have to supply either 24VAC or 24VDC – fortunately I have a bench PSU located not more than 100mm from my test rig. I note that the EasyIO alone consumes 0.1A @ 24VDC. There are two screws located on the front of the FG32 that when removed exposes the circuit board underneath. Against each universal DI or DO, jumpers are provided to change the universtal IO between resistance, current or voltage modes. We decide to wire some outputs to inputs and have one switched DO wire to a resistance input, and a voltage output to a voltage input. This will allow us later to run some feedback tests prior to connecting it to real-world devices. Of course, the range of sensors and devices that can be connected to this device is almost limitless.
The four orange terminals are one each BACnet MSTP and Modbus RTU. Our focus will be on RS485 terminal 2, the Modbus RTU terminal that will provide connection to the EDMI MK7C. Comms to the meter are provided by a RS232 modem port connected to a Smart Building Services Modbus Duo adapter. The adapter provides a dual RS485 bus down one UTP cable along with power – one bus for secure EDMI command line (read/write), and another being Modbus RTU (read only). Standard Modbus holding registers were provided on the adapter and could be polled using the Modbus RTU port on the EasyIO FG32.
Within half an hour, using the CPT Tools commissioning suite, we had real-time polling of the EDMI meter and display onto a very basic HTML5 webpage, hosted on the EasyIO. Another half an hour, and we had single phase kWh meters that provided 2000 impulses/kWh to a resistive DI of the controller, and these numbers also being displayed on the webpage to view. Polling of the meter by default was at around the 3 second mark using the default “normal” polling speed.
Out of the meter, we were obtaining real-time:
- Import Wh (cumulative)
- Export Wh (cumulative)
- Amperage (instantaneous)
- Voltage (instantaneous)
- Watts (instantaneous)
- VA (instantaneous)
- Import Varh (cumulative)
- Export Varh (cumulative)
- Power Factor (instantaneous)
Our next post will show the meter installed along with some kWh circuit meters for a residential project. Following that we’ll take a beginners’ look at the EasyIO commissioning suite – CPT Tools, and then the results of the webpage.