Measuring 20 x 3-Phase Supplies with BMS Integration
Challenge:
Our client had been tasked with installing metering in a food processing facility. They were looking to reduce their energy consumption and costs but needed to understand where their energy was being used. They had a large distribution board with 20 x 3-phase supplies, and they wanted to link their metering to their existing building management system, (BMS). An additional complication was that they could only mount the meter enclosure around 5m from the supplies they were looking to measure.
Solution:
S P Wales worked with the contractor to specify a meter that would feed information into their BMS using the Modbus communication protocol. Unlike traditional CT operated meters which have a 5A input, we specified the ND Metering Solutions Cube 400V with a 0.333V input. This allowed the use of current sensors which have a 0.333V secondary and offer more flexibility in the length of cable that can be used. The CT’s supplied were split-core, meaning they could be opened up and clamped round the required cables without having to disconnect any existing cables.
We pre-wired all 20 meters into a steel enclosure, fitting the panel mount meters onto the front of the enclosure, with all CT links and voltage references fitted inside. By looping both the power supplies for each meter, and the Modbus outputs, the installer only needed to make one connection for each, saving time and ensuring an error free installation.