Integrating power monitoring systems

03/12/2014


Figure 3: The photo shows branch circuit level power monitoring integrated into the writing gutter of a typical electrical panelboard.Q: How large does a power load profile of a commercial building need to be to justify a power monitoring system? To justify integrating the power monitoring system into a BAS or with other engineered systems?

Shapiro: A power monitoring system should be recommended for all commercial buildings regardless of the size. The nature of the system depends on the size and tenants of the building. Power usage at the service as well as throughout the major portions of the distribution facility allow for proper operation of the facility as well as a functional method of understanding the possible maintenance requirements and load growth possibilities without subjecting operating personnel to the risk of arc flash by actually opening electrical equipment to measure loads.

Strang: I don’t think a particular load profile would be the determining factor for justifying a power monitoring system, or for integrating it with an overall BMS. I suppose if you were looking at only ROI of the power monitoring system based on energy savings, you could prognosticate typical payback numbers. I think the criticality of the load would be the biggest factor in implementing the power monitoring system. A strip plaza could have a larger load than a small data center, but the small data center may serve critical 24x7 customers (i.e., a bank) where the data from a power monitoring system would provide much more value.

Yoon: It goes beyond the size of the load profile. To say that a building falls into a specific utility rate class doesn't justify it by itself. Concepts of load profile variability and value of business continuity also factor into it.

Q: How have power monitoring systems helped ensure a building’s power quality is stable?

Shapiro: Power monitoring systems have given operating personnel a tool to diagnose internal as well as external power quality issues. Having power quality monitoring at the facility on a continuous basis allows for immediate identification of power quality issues before they can cause operational problems. As equipment is added to the distribution system or changes are made to the distribution system, the power quality is monitored and anomalies can be identified. The monitoring provides evidence of power quality before and after changes to help identify the causes of power quality issues, help remedy them, and ensure power quality stability.

Strang: Power electronics have come a long way. A 256 sample/cycle analog-to-digital converter is nothing today. Many of the power monitors today can easily achieve this resolution and much higher. This monitoring resolution allows capturing of sub-cycle events and THD that, years ago, required more expensive portable equipment. So, in addition to seeing general trends to ensure power stability, now we can easily see sub-cycle aberrations that can be indicative of equipment that hasn’t quite failed yet but may fail very soon. A power monitoring system can also be very valuable in analyzing what events are produced internally vs. from the utility. For example, a motor starting the same time every day could be easily identified and turned off to see the effect.

Yoon: We have seen situations where utility side power quality issues such as brownouts and single phasing have caused or contributed to equipment failures. However, we've typically seen power monitoring systems used simply to record such disturbances and not necessarily to automatically take equipment offline.

Q: When working with a building’s operations and maintenance (O&M) staff to set up training, systems manuals, etc., what guidelines do you provide for system testing and/or maintenance of the power monitoring system?

Shapiro: EPMS system testing and maintenance goes hand-in-hand with the electrical system testing and maintenance program. As the electrical systems are operated and tested, the EPMS is used to document the positions of circuit breakers, facility load changes, power quality impact of load shifts, etc. As long as the proper signals are received by the EPMS through the electrical equipment and LAN systems, the actual maintenance of the EPMS system and interfaces is limited to the meters and LAN infrastructure, which is minimal.

Strang: When implementing a power monitoring system, testing, commissioning, and training are definitely requirements. We have seen projects where a power monitoring system was installed as part of the original contract, with all of the capabilities intended to be brought back to a PC for remote monitoring and trending. However, the communication cables were never terminated. All the capability was there and the owner was completely unaware. Typically, we specify that the system be completely tested and commissioned by the installer in cooperation with the vendor, and after complete functionality is achieved, a vendor’s representative (of the equipment manufacturer) provides at least 8 hr of training to the O&M staff. Obviously, the actual duration should be adjusted based on the number of staff and complexity of the project, but the goal is for the staff to be comfortable with basic operations before this new system is dropped in their laps. The system will have no value if no one knows how to use it. Lastly, be careful to specify a system that will not hold the customer hostage for minor assistance and changes.

Yoon: One of the biggest gaps that we've experienced in the design process is how to define the look and feel of the HMI and the commissioning of the overall system. Every integrator does things just a bit differently.

Young: For system testing, the specifications are written requiring a 1% calibration between the power monitoring system and calibrated test equipment. A maintenance contract is usually required from respective vendors, as well as 8 hr on-site staff training on all systems.



MAHBUB , TX, United States, 05/28/14 06:56 AM:

Like to see paralleling switch gears. Thanks
The Top Plant program honors outstanding manufacturing facilities in North America. View the 2015 Top Plant.
The Product of the Year program recognizes products newly released in the manufacturing industries.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
World-class maintenance: The three keys to success - Deploy people, process and technology; 2016 Lubrication Guide; Why hydraulic systems get hot
Your leaks start here: Take a disciplined approach with your hydraulic system; U.S. presence at Hannover Messe a rousing success
Hannover Messe 2016: Taking hold of the future - Partner Country status spotlights U.S. manufacturing; Honoring manufacturing excellence: The 2015 Product of the Year Winners
The digital oilfield: Utilizing Big Data can yield big savings; Virtualization a real solution; Tracking SIS performance
Getting to the bottom of subsea repairs: Older pipelines need more attention, and operators need a repair strategy; OTC preview; Offshore production difficult - and crucial
Digital oilfields: Integrated HMI/SCADA systems enable smarter data acquisition; Real-world impact of simulation; Electric actuator technology prospers in production fields
Improving flowmeter calibration; Selecting flowmeters for natural gas; Case study: Streamlining assembly systems using PC-based control; CLPM: Improving process efficiency, throughput
Putting COPS into context; Designing medium-voltage electrical systems; Planning and designing resilient, efficient data centers; The nine steps of designing generator fuel systems
Warehouse winter comfort: The HTHV solution; Cooling with natural gas; Plastics industry booming

Annual Salary Survey

Before the calendar turned, 2016 already had the makings of a pivotal year for manufacturing, and for the world.

There were the big events for the year, including the United States as Partner Country at Hannover Messe in April and the 2016 International Manufacturing Technology Show in Chicago in September. There's also the matter of the U.S. presidential elections in November, which promise to shape policy in manufacturing for years to come.

But the year started with global economic turmoil, as a slowdown in Chinese manufacturing triggered a worldwide stock hiccup that sent values plummeting. The continued plunge in world oil prices has resulted in a slowdown in exploration and, by extension, the manufacture of exploration equipment.

Read more: 2015 Salary Survey

Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Society for Maintenance and Reliability Professionals an organization devoted...
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
This article collection contains several articles on the vital role that compressed air plays in manufacturing plants.
This article collection contains several articles on the Industrial Internet of Things (IIoT) and how it is transforming manufacturing.
This article collection contains several articles on strategic maintenance and understanding all the parts of your plant.
click me