To Jarek Bras, preserving the quality of power delivered to electrical equipment is a lot like performing a routine tune-up on your car. Service the car, and it will drive more smoothly and ultimately use less fuel. As senior product manager for Amprobe, a business unit of SPX Corp. based in Miramar, Fla., it's Bras' job to develop products that help customers achieve a similar objective: increase the efficiency of their equipment while consuming less energy.

“With the rising cost of energy, dependence on foreign oil, and global increase in energy consumption, there is a significant focus on making electrical systems as efficient as possible,” says Bras. “By monitoring and properly maintaining electrical systems, their efficiency could be increased more than 30%.”

That's where the company's line of power quality recorders — the latest of which launched in March at Electric West in Las Vegas — comes into play. Developed out of a growing need for a more affordable power quality analyzer, the DM-4 is capable of performing a complete spectrum of measurements like more expensive models. The initial goal with the DM-4, says Bras, was to offer a sophisticated power quality tool capable of recording the same parameters as its higher-end counterparts but at a more modest price point. Listing at $3,495, the device delivers on the financial front as well as satisfies the analysis objective, capturing up to 500 parameters simultaneously, including fast spikes.

One of the most unique features of the DM-4 that differentiates the device from its competitors is its pocket-size Remote User Interface. In addition to the box recorder, this PDA functions as a standard built-in display, recording all parameters and providing real-time viewing and analysis of the results through the company's Download Suite. Users can transfer recorded information from the DM-4 to the PDA and then to a PC in the office, while the recorder remains “working” in the field. Users also have the option to connect the DM-4 directly to the PC for independent use.

Another benefit is that the unit is protected against setup changes by unauthorized individuals during recording. Setup is simple. Using the Remote User Interface's touchscreen, technicians can simply tap on the parameters that they wish to record.

“Under the Basic mode, the parameters are grouped, so there are only a few check boxes to select,” Bras says. “For example, when the Voltage check box is selected, the device is going to record all voltages on all phases, or if the Current Harmonics check box is selected it will record all harmonics from DC to the 51st. For users who want more control, the Advanced setup is available, where each of the individual parameters can be selected individually.”

Because Mark Snead already uses a Palm pilot for business, the DM-4 was immediately appealing when it was time for him to look for a new PQ tool. Snead is president of MultiNet, an electrical and voice/data services company based in Alexandria, Va. After using older data recorders in the past that printed data on paper rolls, Snead was optimistic about the portability and functionality of the Palm feature of the DM-4.

Using the DM-4 to troubleshoot a 3-phase, 208V, 400A circuit at one client location, he left the unit connected for 48 hours. “The load on two phases would ramp up quickly and intermittently for reasons unknown,” he says. “At first, we discovered some loads that the customer was unaware of. Secondly, the DM-4 revealed a voltage drop situation that contributed to the higher loads. It was very convenient to have the data automatically loaded in my Palm Pilot for show and tell during meetings with the client.”

From a technical standpoint, Snead also likes the fact that the DM-4 literally puts all of the harmonics readings at your fingertips, including spikes, voltage, amperage, and power factor. “All you have to do is click on the heading with the stylus to open the various windows,” he says. “This makes the DM-4 much simpler to use.”

So simple, contends Bras, that even a toddler can do it. “I actually tested it with my five-year-old and he was able to set it up in just a few minutes,” he says. “It takes me less than 5 minutes to train people on the DM-4.”

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Product Features

  • Features true RMS capability

  • Comes with carrying case, CTs, test leads, PC software and download cable, remote user interface PDA with protective hard case and interface cable

  • Works with single- and three-phase systems

  • Detects and records voltage sags, surges, and spikes (100 nsec or slower)