Three energy meter selection tips

Energy saving designs: Consider how long energy data collection is needed, how many phases and accuracy, and how the data should be collected.

By Drew Knobloch February 13, 2020

Many reasons go into specifying an energy meter for a project including LEED requirements, local building codes, or a desire to understand how and where energy is being used in a building or facility. Most customers want to decrease or optimize their energy usage, either for financial reasons or environmental concerns, but are unsure where to start.

For many customers, the only measure of energy usage is a utility bill, which is an aggregate of all energy consumed within a building. The first step to learn more about energy usage in a building or facility may be an energy audit. This gives the customer a view into the overall energy usage of the facility, a breakdown of which circuits are using the most energy, and when the usage is heaviest. Once the existing usage is understood, the customer can use this data to create targeted programs that reduce usage in specific areas such as lighting, HVAC, or upgrades to building efficiency.

Three questions to ask when selecting an energy meter

Selecting the correct meter for a project can be straightforward by asking a few basic questions.

1. How long will data collection occur? If the need is temporary, selecting a simple data logging device may be enough. However, there’s need to collect data over a period of months, a permanent installation may be the answer.

2. How many phases need to be measured, and what accuracy is needed? Select a meter with enough capacity to monitor all the loads and phases that are needed. If data will be used for billing purposes, a meter and current transformers with higher accuracy may be needed.

3. How should data be collected? The two primary methods are individual collection and integration into a building automation system. For one meter, it may be adequate to download the data on a periodic basis over a USB, wi-fi or Ethernet connection. For larger installations, a direct interface with the building automation system via BACnet or Modbus can continuously retrieve energy data for analysis.

Measurements enable savings

The data is only as good as the installation. Ensure the data is accurate and the equipment lasts by selecting a reputable partner for installation and service.

Once baseline data is obtained and a targeted energy reduction program is developed, the meter data will show how effective measurements are at reducing overall energy usage. Use the data to determine if the program is producing the desired results, or if changes need to be made in the program parameters to meet desired energy reduction goals.

The energy landscape is fluctuating, and a durable, accurate metering program can provide the information you need to make business decisions in a changing environment.

Drew Knobloch is senior product manager, Siemens. Edited by Mark T. Hoske, content manager, Control Engineering, CFE Media, mhoske@cfemedia.com.

KEYWORDS: Automation design, energy meters

Energy measurement needs are application dependent.

When specifying an energy meter consider length of measurements and accuracy.

How should energy data be collected?

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Changes to reduce energy use benefit from accurate measurements. Are you using energy meters?


Author Bio: Drew Knobloch is senior product manager, Siemens