APP NOTE: Metering Project – Managing Energy Usage with Ethernet I/O
Managing Energy Usage with Ethernet I/O
Defining the Problem:
The university power plant produces both electricity and steam for the campus. The chilled water and steam condensate need to be monitored and recorded by totalizing the pulsed outputs from magnetic, positive displacement, and vortex flowmeters. The volumetric flow rate, along with the liquid heat loss from the steam-to-heat transfer process, is used in steam cost calculations to better manage the energy demand across the campus.
• The university requires consistent installations that can be duplicated across the campus.
• Communication with the data historian software, eDNA, via modbus TCP/IP over the campus Ethernet network.
Implementing the Solution:
1. Connect a PC to the 989EN-4016, open an internet browser, assign the network parameters and configure the discrete inputs as counters to totalize the flowmeter pulse outputs.
2. Simulate input pulses and observe the count increase in the 989EN-4016 counter test page.
3. The eDNA software periodically reads the current count value of each input from the 30,000 modbus input registers or the 43,000 holding registers. Two registers of 16-bit unsigned integer values yield a 32 bit totalized count value.
- BusWorks Discrete I/O 989EN-4016
Notes: 989EN-4016 modules have 16 discrete I/O where
each channel can be an input or an output. Optionally, this models allows the first 8 channels to be used as non-volatile pulse counters with the remaining 8 channels available as local output alarms for their associated input counters
The 989EN-4016 module is an affordable, versatile discrete and counter/alarm remote I/O. With fast installations and Class 1 Div 2 ratings, duplication across the campus was easily achieved. Additionally, the campus data historian software was quickly programmed to communicate with the 989EN solution.