Branch level monitoring
From Local
Introduction
Branch-level power monitoring is to instrument the power usage at a circuit breaker level. While power usage at a branch-level can be measured by reading the output current of a current transformer wound around a circuit breaker wire, the complexity of deployment increases when we are to measure the power usage of an electric panel of a building which contains tens of circuit breakers. This problem has been well addressed by commercial level panel monitoring instruments such as Veris E30. Veris E30 reads the current of multiple circuit breakers using a current-transformer array, processes the sampled data, and provides it over the RS485 serial bus using Modbus RTU protocol. While this can be a reasonable solution to monitor a few Veris E30 devices, but it is not scalable because it requires wiring over RS485 serial bus and interfacing to an RS485 master (e.g. PC that interfacts over RS485 bus). A better approach is to utilize the infrastructure of the Internet, which allows us to monitor and control the panel level instrument over the Internet and to scale over the LAN infrastructure in a building.
Status
- Veris E30 is installed for the electrical panel that covers the half the area of RAD lab in Soda Hall. As of now we monitor the voltage and the current of each circuit breaker. In the next scheduled electrical work, we plan to add instruments to measure the current of the mains, where all the circuit-breaker wires in the panel is from.
- A working C library and client application that sends a command and receives the data from the Veris E30 device.
- A working web service over the C library is written and is installed in a server machine [link].
Related Document
- Application Protocol for Veris E30 Panel-board Monitoring System [PDF] : A technical report on initial deployment of Veris E30 panel-board monitoring board and description on TCP/IP interface that wraps the low-level MODBUS interface of Veris E30.
