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In principle this type of probe can be used at any frequency, but at DC and lower frequencies circuits often have high impedances that would be unacceptably loaded by the probe's low 500 or 1000 ohm probe impedance. Parasitic impedances limit very-high-frequency circuits to operating at low impedance, so the probe impedance is less of a problem.
Electric power quality is the degree to which the voltage, frequency, and waveform of a power supply system conform to established specifications. Good power quality can be defined as a steady supply voltage that stays within the prescribed range, steady AC frequency close to the rated value, and smooth voltage curve waveform (which resembles a sine wave).
Switched-mode power supply units (PSUs) in domestic products such as personal computers often have universal inputs, meaning that they can accept power from mains supplies throughout the world, although a manual voltage range switch may be required. Switch-mode power supplies can tolerate a wide range of power frequencies and voltages.
Note the connection of the security system to the phone line requires a wiring configuration that allows the security system to disconnect all phones in the home when it needs to connect to the monitoring center. This is critical, if the wiring is not correct the system may not communicate back to base when an intrusion is detected.
This is useful when sudden turn-on in the middle of a sine-wave half-cycle could cause undesirable effects like high-frequency spikes, for which the circuit or the environment is not expected to handle gracefully. The point where the AC line voltage is zero is the zero cross point. When a TRIAC is connected in its simplest form, it can clip the ...
Lighting and general purpose receptacles are at 120 volts AC, with larger devices fed by three wire single-phase circuits at 240 volts. In commercial construction, three-phase circuits are often used. Common 3 phase configurations within a building are 208v/120 wye, 120/240 center tapped delta and 480v/277v wye. Lighting is usually fed by 277 V ...
Droop speed control is a control mode used for AC electrical power generators, whereby the power output of a generator reduces as the line frequency increases. It is commonly used as the speed control mode of the governor of a prime mover driving a synchronous generator connected to an electrical grid.
These present a high impedance only at high frequency, so they will effectively stop radio frequency and digital noise, but will have little effect on 50/60 Hz noise. Reinforce the shield of the signal cable connecting C1 and C2 by connecting a thick copper conductor in parallel to the shield.