Key Features in a Quality Power Analyzer
In our research, we found 50+ unique power analyzer models currently in production, and dozens more that are discontinued but still functional and valuable. With so many choices, it is hard to narrow down which ones are the best and if they are worth the price. To make things easier, we have identified some important features to look for when considering power analyzers.
The Bare Minimum
Any power analyzer should have these essential measurement types
- Voltage, current, power, apparent power, power factor, THD, frequency, phase angles, and rudimentary power quality characteristics
- Single-phase, split-phase, three-phase delta & wye, four wire delta, and DC system configurations
Analyzers should also come with a complimentary software for organizing data, analyzing data, and creating reports.
Recommended safety rating: Overvoltage category IV for 600V; category III for 1000V
Ease of Use
A power analyzer is a sophisticated device that may be complicated and difficult to use for someone that has had limited or no experience with one. Having an intuitive, easy to use analyzer that minimizes errors is what to look out for. It should feel like the people designing it know what it is like to use it in the field, which unfortunately is not the case with every power analyzer. Even if you intend to do all your analysis on a laptop, look for a measurement display and keypad so you can control the analyzer and get quick results if a laptop is not there or cannot communicate with the analyzer. There should also be a way for working around the normal setups and interfaces to accomplish whatever specialized measurements or study you need to do.
The analyzer should be your trusted partner for use in a mobile and industrial environment for years to come. It’s difficult to determine the longevity of a device without using it. Customer reviews can help paint a picture, but also check the warranty coverage. Manufacturers that include a generous warranty have confidence in their products and are willing to repair or replace parts, including batteries, if anything happens. There also should be a means for extending its useful life through renewing your warranty and receiving updated and enhanced software and firmware for years into the future.
Whether for storing the analyzer in a locked electrical panel during monitoring or holding it in your hand, smaller power analyzers are more practical. Most power analyzers are relatively large, heavy, and overall cumbersome (and they’re usually not any better when bigger!).
Redundancy in Communications and Storage
You never want to find you don’t have the information you need at the end of a monitoring session. Make sure there is redundant memory storage so there are dual copies of the logged data. Also make sure there are multiple ways to get the data out of the analyzer, in case one method is not working for any reason.
There is little benefit to your analyzer if you cannot operate it when needed. Look for knowledgeable real-time technical support and fast turnarounds for repairs, upgrades, and calibrations. You only generate revenue or answer power questions when your analyzer is doing what you need it to do, when you need it to.
Here are some of the measurement capabilities and features that come in handy for electrical contractors.
- Ampacity & load monitoring
- Power quality analysis
- Energy & cost analysis
- Error-elimination features and sequences
- Wide range of measurement accessories (e.g. precise or wide-range current probes)
- Measurement display and full keypad
- Multiple operating modes to support any power system you will ever need to monitor
- Project management software for efficient and error-free management of logged data (and tracking equipment performance over time)
Bonus: Overrated & Irrelevant “Benefits”
There are some specifications that manufacturers pass off as big advantages but do not make a difference in user experience and results in most cases. Here are some examples:
Class A: The IEC61000-4-30 standard for power measurement has three classes: B, S, and A. Class A, being the highest-level requirement, is a big selling point for models that meet that standard. Its requirements include capability to measure interharmonics, mains signaling, flicker, time synchronization, and a 200ms measurement interval. Often, these are of minimal value in the US, so don’t overpay for a “Class A” analyzer if you do not plan on using these features. Also, some analyzers actually exceed the requirements of Class A in some areas but don’t meet it in others, so don’t assume an analyzer that does not meet Class A is inferior.
Measurement Resolution and Accuracy: Some power analyzer manufacturers mask the accuracy of measurements by providing extended “resolution” or by adjusting the way the measurement is made. Here are a couple examples:
- If a specification says harmonics are accurate to 1%, but harmonics are displayed in tenths of a percent, the analyzer is not more accurate than one with the same accuracy that displays to the nearest rounded percent.
- A specification says frequency is accurate to an impressive 0.01%, but it measures frequency over a 10 second average. It may actually be less accurate than the analyzer that measures frequency each second (or faster) but claims just 0.1% accuracy
More precise resolution or tighter accuracy specs do not necessarily mean a measurement is more accurate, but they give that impression, so you should not accept statements or impressions of accuracy without question.
Touchscreen: When operating a power analyzer during monitoring, users will often be wearing protective gloves, rendering the touchscreen feature useless. Pressure-sensitive touch screens and/or ones that include a stylus provide a good workaround, but the highest resolution is always available from a wirelessly connected laptop. As long as the analyzer has the ability to display measurements and have its operating mode changed, the basics are covered. Weigh how much more the touchscreen is worth to you.