The 428B measures direct current without interrupting your measured circuit or producing loading errors. DC current is measure by utilizing a clip-on transducer that converts the magnetic field around the conductor to an AC voltage proportional to DC current. This voltage is detected and displayed as direct current. Since no contact is made to the circuit, complete DC isolation is ensured. Low frequency currents up to 400 Hz can also be measured by connecting an oscilloscope or voltmeter to the front panel.

SPECIFICATIONS:
• DC Current Range: 1 mA to 10 A full scale nine ranges
• Output: variable linear output level with switch position for calibrated 1 V into open circuit
• Frequency Range: DC 20 400 Hz (3 dB point)

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