“An investment in knowledge always pays the best interest.” – Benjamin Franklin
Surges, transients, and temporary over-voltages are all forms of over voltage and confused by the often loose and interchangeable use of terminology. A way of understanding the significance of each, however, is the duration or each event.
Surges have a greater energy component and last for >10 microseconds & <1 milliseconds, charring the electronic components and appliances.
Transients, on the other hand, have a much shorter duration (<10 microseconds) with relatively low energy content, but significant in voltage to confuse data logic and cause lock-ups or unexplained data corruption.
Over-voltages are created by faults on the utility power distribution system and can cause extensive damage since their time domain is much longer (milliseconds to seconds to hours). Note while UL 1449 (Second Edition) ensures that the Surge Protection Devices (SPD) will not create a fire or safety hazard under these conditions, SPDs are not designed to protect against over voltages.
Protect yourself, your equipment and your company’s integrity by taking these power related symptoms out of the equation when performing service calls. It will lead to better cost management and higher service agreement profitability.
NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)
Surge Protection Institute