Surge Generator Rental - Combination Wave & Voltage
Combination wave surges are simultaneous, fast, high voltage and high current pulses that together replicate many real world EMI issues including lightning strikes and power grid switching.
CDNs are devices commonly used in testing for transient and other immunity pulses where they are applied to power lines (or data lines) going towards the EUT/DUT (coupled) and subsequntly removed (decoupled). These networks allow the equipment under test to be running while experiencing the surges allowing evaluation of the impact on the operation of EUT. The requirements for the CDNs are typically guided by the underlying standard, commonly IEC 61000-4-5 for combination wave surges, and typically have specific requirements for both power and data lines. We offer rentals of a wide variety of both data line and power couplers up 125Amps making us an ideal resource for additional testing capabilities.
Surge generators provide the necessary waveforms or pulses to simulate over-voltages from switching and lightning transients to replicate the anticpated electrical environment which the equipment will operate. These tests are designed to ensure products are robust enough to withstand the rapid, high engery pulses. The associated waveforms are typically categoriezed by type of pulse, voltage, current, or combination wave (having both current and voltage components).
Most common surge generators include a pulse generator, interface, and built in coupling decoupling network allowing them to meet a variety of common testing requiremetns. Many also include software and programmable test routines assisting in more complex and quicker testing.
Surge generators interface displays and software will vary by manufacturer and model, however there are a few steps that are universal when contaducting testing with these systems.
The video on the left with the Haefely Axos 5 test systems provides a guide on setting up a surge generator designed for compliant testing to IEC 61000-4-5. In the video power on testing is being conducted through the use of the coupling decoupling network as means (CDN).
The direct injection method is the application of surges to a equipment under test through direct connection from the generator without using any coupling decoupling network (CDN) or coupling device. This is commonly done through a direct out connection on either the front or back of the system and is used exclusively for power off testing.
Coupling decoupling networks are the most common method of applying surges to equipment under test. This allows for equipment to be powered through the CDN going towards the device under testing and following testing the pulse is removed not impacting the power supply. These are typically categorized by both AC and DC as well as the voltage and current levels. CDNs are generally seperated by both manual and automatic as well as the criteria above. When testing is commonly conducted a series of lines are tested, L-N, L-G, etc. Manual coupling networks require a physical change in cabling configuration to meet the particular lines that are to be tested, increasing the time needed to complete testing.
Surge pulses are generally categorized by the rise time, duration, and test level given a constant source impedance. Many of the most common surge pulses are defined in this way as many of the other requirements for the waveform are relatively small. It common to define many combination wave pulses, having both voltage and current waveforms, by the voltage. (IE 15kv combination wave generator, the 15kV referring to the max open circuit voltage) The correlation between the voltage annd current levels make this an easy distinction.
The image diminstrates a common 1.2/50 - 8/20 µs pulses with the 1.2/50 being the rise time and duration of the voltage waveform (open circuit) and8/20 µs the rise time and duration of the currnet waveform (short circuit).