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Self-Powered AC Line Frequency Monitor with 0.01Hz Resolution

  • Recommended In Production

    Explanation of Product Status

    Under Development Products under development
    Please contact us for product availability and sample lead-time.
    In Production Product is in mass production.
    to be discontinued Not recommended for new designs. We are evaluating the schedule for the discontinuing of production of this item. Contact Murata or refer to the website for details of product supply and possible alternative product information.
    Discontinued product Production of this product has stopped. Contact Murata for inventory availability and possible alternative products.
    Recommended product This product is particularly recommended among our products currently in production.
    New product It's new item.


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Technical Information

Series DMR20-1-FM
Series Headline Self-Powered, LED Display, AC Line Frequency Monitor
Series Description Murata Power Solutions’ new DMR20-1-FM is the world’s smallest, self-powered, ac line frequency monitor. Simply connect 85 to 264Vac (45-65Hz) power and the meter is fully operational—no additional components are required. The unit can also measure distorted 120Vrms power sources with triangle and square waveforms, as well as quasi sine wave outputs of dc to ac power inverters. An ultra-stable, quartz-crystal controlled microprocessor provides accuracies of ±0.02Hz over the operating temperature range of -25 to +60°C. DMR20-1-FM frequency monitors feature a large, 0.30”/7.6mm, bright LED display that can be easily read from 10 feet away (3 meters). A built-in resettable fuse and out-of-range indication assures long term reliability. The DMR20-1-FM is housed in a rugged, round polycarbonate case that provides excellent protection against moisture, dust, shock and vibration. Panel installation is straightforward: using available tooling, simply drill and punch a 1.2 inch (30.5mm) diameter hole and anti-rotation notch, insert the meter and gasket, and securely fasten the meter using the supplied hex nut. The nut and gasket are designed to provide moisture ingress protection to IP67/NEMA 6. DMR20-1-FM is exactly the same size as Murata Power Solutions’ DMR20-1-ACV (ac volts), DMR20-10-DCM (dc volts), and DMR20-1-TMP (temperature) digital panel meters.
Quality UL/CSA recognized
Measurment Type AC Line Frequency
Measuring Range 85 to 264V
Measuring Condition 85 to 140Vac
Resolution (V) 0.01
Accuracy +/-0.01Hz
Display Type LED
Color Red
Number of Digits 4
Digit Height (inch) 0.3
Digit Height (mm) 7.6
Update Rate (samples /sec) 2 to 3
Power Supply Type 2-Wire Self Powered
Power Supply (V) 85 to 264
Power Supply Current (mA) 12
Operating Temp. Range (C) -25 to 60
Mounting Type Panel Mount
Humidity 0 to 85%
Weight (oz) 0.9
Weight (g) 25.5
Case Material Polycarbonate
RoHS 6 Yes