The Amazing Benefits of High Voltage Probes
A high-voltage differential probe is a must-have piece of test equipment for anyone who wants to safely explore high voltage signals on a standard oscilloscope. For safety reasons, the ground side of your oscilloscope probe is connected directly to the main earth. This means you can only test earth-referenced or really floating signals, such as those seen in battery-powered circuits where one component can be linked to mains earth via the scope. But what if we want to monitor some signals in a circuit that isn’t linked to the mains, such as a switch-mode power supply off-line? The negative side of the rectified mains is normally connected to the control circuit. This is clearly not the maximum capacity of the earth. Your oscilloscope will make a straight shot to earth if the ground clip of a conventional oscilloscope probe is connected to this position. The circuit under test would almost probably be destroyed, and your oscilloscope would almost certainly be damaged.
Series of VMP Probes
The Ross VMP HV probes are designed for use in hand-held portable applications with an insulated handle or for fixed attachment. Digital multimeters, oscilloscopes, and many types of panel meters employ portable capacitive, resistive, or compensated varieties. Capacitive types are utilized for wideband and pulse work, whereas resistive kinds are used for DC and 50 or 60Hz AC or other particular single frequency sine waves. In both the VMP and VD Series, compensated resistance/capacitance wideband DC to 1MHz (or more) variants are favored for the common applications.
For high-voltage measurements, select the appropriate probe.
For the sake of this discussion, any voltage that exceeds the normal range of a standard DSO equipped with a 10X passive probe is termed “high voltage.” The maximum input voltage for the TDS 220 when using a standard P6112 Probe is 300 V RMS or 424 V DC + peak AC. The observed signal must be totally contained within the scope graticule’s eight vertical divisions for most measurements. To fit within the graticule, signals that surpass this threshold must be decreased. Because of its 100X attenuation, the P5100 High-Voltage Passive Probe is a great choice for this application, extending the TDS 220’s effective range to 2500 V. The P5100 High-Voltage Passive Probe is the tool of choice for safe ground-referenced measurements at high voltages. Its 100X attenuation increases the TDS 220’s effective range to 2500 V. The P5100’s large bandwidth (up to 250 MHz) ensures that transients and quick signal edges are captured intact. It’s UL 3111-1 and IEC 1010 approved for voltages up to 2500 V (DC + peak AC). The P5100 also has the tough physical build that is required for power measurements. On test points up to 6.5 mm in diameter, its distinctive retractable hook tip ensures a secure connection.
The Unit-Under-Test (UUT) of a Motor Drive is a control board located within a “cell.” A major manufacturer of conventional and harmonic drives for high-power AC electric motors used in HVAC systems, oilfield pumping equipment, and other applications is a major manufacturer of conventional and harmonic drives. A system may contain a large number of modular power cells. Each must pass severe production quality inspections to ensure not just client delight but also customer safety. The cells use IGBT (Insulated Gate Bipolar Transistor) devices to power the load. The digital ICs on this board are controlled by a logic board that is built into the cell and is supplied by low-voltage supplies acquired from the system’s transformer secondary voltage. The conversion from line input to the requisite 15 VDC level is handled by a local regulator.