Ultrasound Power Meter - Digital - 2 mW Resolution
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Ohmic Instruments 3081 Elm Point Industrial Dr. St. Charles, MO 63301 ULTRASOUND POWER METER Approved Electronics www.ohmicinstruments.com Sales: sales@ohmicinstruments.com Service: service@ohmicinstruments.com FIVE POINT CERTIFICATION (NIST TRACEABLE) HIGH RESOLUTION: 2 OR 20mW (1.5 or 15 mW in grams mode) MEASUREMENT RANGE: 0-30 WATTS MEASURES TOTAL PULSED OR CONTINUOUS POWER AUTOMATIC ZEROING & STABILIZATION DIGITAL DISPLAY & RS-232 INTERFACE EQUIPPED WITH CARRYING CASE UPM-DT SERIES WATTMETERS VERIFIED BY NIST & FDA OHMIC Instruments Models UPM-DT-1PA & 10PA are precision wattmeters designed to measure the power output of diagnostic and therapeutic ultrasound transducers. The UPM-DT series have been in use worldwide since 1986 and conform to the testing guidelines recommended by FDA, JCAHO, AAMI and AIUM. Power is measured by the radiation methodand the accuracy of the UPM-DT’s are traceable to NIST. Principle of Operation The most reliable and repeatable means of measuring ultrasound power is the radiation force balance method. The transducer to be tested is centered above a 45° air-backed cone target in water media, which is linked to a precision balance capable of resolving 0.1 or 1.0 mg. When acoustic energy is applied to the cone, the resultant force exerted on the load cell of the balance is directly proportional to the total radiated power. The test tank is lined with sonic absorbent rubber to prevent power reflection. The balance is programmed to convert milligram magnitude forces directly to a readout in watts with resolution to the nearest 0.002 watt for Model UPM-DT -1PA and 0.02 watt for Model UPM-DT-10PA. Verification of the UPM-DT-Series is easily accomplished by placing a calibrated weight on the arm of the target cone. (A 1-gram weight is equal to 14.65 watts.) OHMIC also maintains NIST traceable mass and ultrasound standards, therefore the units can be returned for periodic recertification. The Importance of Calibrating Ultrasound Transducers It is important to measure ultrasound power levels to verify correct patient exposure and reduce potential risks. All diagnostic and therapeutic Doppler and ultrasound equipment should be tested periodically. Typical safe values are defined by the temporal average intensity at the point in the acoustic field where the intensity is at its maximum value, referred to as Spatial Peak Temporal Average (SPTA ). The FDA and AIUM provide guidelines for the maximum SPTA values in medical applications. Typical safe SPTA values are 10mW/cm 2 for echo sounding, 100 mW/cm2 for Doppler devices and 3W/cm2 for therapeutic use. The watt density (watts/cm 2) of a transducer is determined by measuring the total power output and dividing by the active cross sectional area of the transducer. A sample form to document and report ultrasound performance is included in the manual. WARRANTY: All products manufactured by OHMIC Instruments are warranted to be free of defects in material and workmanship for one year after delivery. Any equipment found to be defective within this period will be repaired or replaced free of charge

* Power packs and cord sets are available to meet any configuration or VAC needed. UPM-DT Series Ultrasound Power Meters feature a high contrast alphanumeric LCD display. Membrane "touch buttons" enable quick setup, automatic zero, selection of units for the power reading (grams or Watts "custom"), and printer control. The cone target and transducer positioner. (Tank not shown.) The rear panel of the UPM-DT Series showing RS-232 and printer ports. ENGINEERING SUPPORT: OHMIC Instruments designs and manufactures a full line of environmental and bio-medical sensors, instruments and controls....