Joost Giesbers, Lead Engineer Measurements
In general, we can distinguish two methods for measuring electrical phenomena: interval-based measurement and continuous waveform recording. Both types are suitable for specific applications. In which cases does measuring predefined factors at regular intervals suffice? Some examples: recording trends, average voltage levels, harmonic loads, or dip/swell frequencies over a relatively long period. Or in cases when only statistics (such as voltage variations, harmonic levels, or flicker) are needed, and there is no need for continuous insight into the sinusoidal waveform. Continuous Waveform Recording measurements, on the other hand, are useful for detecting short-term, complex problems (such as disruptive transients) or for analyzing waveforms during malfunctions. In this article, I’ll be delving deeper into this topic.
Continuous Waveform Recording
With Continuous Waveform Recording (CWR), voltage and current are continuously recorded. Unlike traditional interval measurements or recordings that are only activated after a predefined threshold has been exceeded, CWR provides a complete, uninterrupted view. This measurement method enables detailed analysis of disturbances such as harmonics, voltage spikes (transients), and dips. Traditional measurements often miss very brief or subtle issues, whereas CWR can accurately capture these. Phenomena that only last a few milliseconds, which would otherwise go unnoticed, can be thoroughly analyzed with precision.
CWR makes it possible to conduct precise research into rapid events, for which it is crucial to analyze the exact shape of the voltage or current wave (sine wave), rather than just individual data points. For CWR, advanced measuring instruments are required, with high resolution, storage capacity, and analysis capabilities. Equipment must comply with international standards (such as IEC 61000-4-30 Class A). Proper configuration, expert interpretation, and regular updates are essential. It’s also vital to pay attention to the sampling frequency and ensure smart data management to efficiently work with large amounts of measurement data. Through continuous monitoring, deviations can be detected and addressed early, preventing malfunctions and unnecessary energy consumption. This increases efficiency and helps organizations comply with standards such as EN 50160. CWR supports predictive maintenance and provides insights into energy consumption, leading to optimizations in load patterns.
The Elspec Pure BlackBox
A traditional meter captures measurement values at fixed intervals, and the raw measurement data is not retained. The Pure BlackBox, however, stores all raw measurement channels and is the only handheld analyzer that continuously records more than 5,000 Power Quality parameters, such as RMS, THD, harmonics, and voltage spikes, without interruption. Thanks to smart data storage, the significant potential drawback of Continuous Waveform Recording—massive amounts of data—is resolved. The innovative patented PQZIP technology, compresses data in real-time, enabling months or even years of storage without issues.
Using this meter, measurement can continue indefinitely. The meter is connected and keeps measuring—even for years on end, if necessary—until a malfunction occurs. This approach results in a complete overview of all collected data, allowing precise tracking of a device or installation’s performance. Measurements start as soon as the meter is powered on and only stops when it is turned off. Once the meter is connected to a system with the accompanying software installed, live data can be read out—that’s not possible with many traditional meters.
A smartphone can be used as a screen, instead of a traditional display. Using the app, all measurement data can be easily read and managed. This may take some getting used to, but ultimately, it offers much greater flexibility and convenience. As with any new technology, its use requires some adjustment, but the benefits are clear. Because virtually nothing needs to be configured, the chance of missing data is very small. You don’t have to rfind outthat you should have chosen a smaller measurement interval, for example, after the fact. The meter is not only highly suitable for Power Quality measurements but also for many other applications. Large industrial parties and companies that regularly receive questions about machine performance, overload, or available capacity in installations can gain deep insights with it.Installers and installation managers also benefit from this technology: they can provide substantiated answers to complex technical questions. If desired, the measurement data can also be analyzed by HyTEPS.
Comparison of measurement methods
| Interval-based (Periodic logging) | CWR (Continuous Waveform Recording) |
| Advantages – Limited data volume, low storage requirements – Suitable for long-term measurements and trend analysis – Simple, clear dataset (aggregated per interval) | Advantages – Highly detailed information (all signals) – All parameters can be determined retrospectively – Also records transients and short disturbances |
| Disadvantages – Low time resolution – misses very short events if not triggered – Only predefined parameters and intervals are available – Not suitable for in-depth waveform analysis – No indefinite-time measurements | Disadvantages – Very large amounts of data due to more data points per time unit – high storage and processing requirements – Requires advanced equipment and software |
| Typical Applications – Long-term network monitoring (weeks/months) – PQ compliance measurements (EN50160 over a week) – Trend analysis of quality parameters over time | Typical Applications – In-depth troubleshooting of PQ issues – Short, detailed measurement campaigns – Capturing infrequent or very fast events |
Pure BlackBox Handheld Power Quality Analyzer with CWR
- Extensive, continuous monitoring and recording of Power Quality data
- Detect and analyze PQ issues using precise measurements
- Three-phase version that can also perform single-phase measurements
- Easy-to-use plug-and-play device
- No need to configure event recording
- Continuously records all Power Quality parameters
- No need to set threshold values
- Waveform measurements: 256 Samples/Cycle at 50/60Hz
- Includes battery add-on – when power is lost, meter keeps measuring for several hours
- Measures up to the 128th harmonic order
- Can be connected to live analysis software
- Up to five hours of battery life (with the add-on module; otherwise, 30 seconds)
When purchasing the Pure BlackBox, you not only receive a state-of-the-art meter but also comprehensive training, specifically designed to help your team utilize the analyzer optimally. This training, provided by HyTEPS, focuses on the effective use of the Pure BlackBox analyzer for monitoring and improving Power Quality in electrical installations. Our experts conduct extensive training four times a year. This is included in the purchase price. In this way, expert use of the analyzer is guaranteed, ensuring you get the most out of your investment.
The handheld Pure BB is also available in a version designed for permanent installation, such as a panel meter.
For this application, we would like to refer you to the G4400 series from Elspec.