We've included this handy glossary to help with the terminology & abbreviations relating to power products. Pick a letter below to begin, or download the glossary to refer to it whenever you like.A B C D E F G H I J K L M N O P Q R S T U V W X-Z #
Abbreviation for temperature (in °C).
Unit of width (usually) in a 19 inch rack. 1 TE = 1 HP = 0.2 inches = 5.08mm.
The average percent change in output parameter (usually voltage) per degree Centigrade change in ambient temperature over a specified temperature range. (Expressed as %/°C). See also Ambient Temperature.
The amount by which power supply or component ratings are decreased to permit operating at elevated temperatures.
SI prefix multiplier. Multiplies by 1012. So 1 THz = 1 x 1012 Hz. Written as 'tera'. Abbreviated to 'T'.
Shuts down a power supply (PSU) if its internal temperature (or the temperature of specific components) exceeds a predetermined limit.
A condition in a component where increasing temperature results in increasing losses bringing about a further temperature increase and so on. If left unprotected, this leads to failure.
A device which changes resistance with temperature. In power supplies, negative temperature coefficient thermistors frequently are used as inrush current limiting devices.
A voltage regulator in a standard 3 terminal transistor package.
Combination of three alternating currents having their voltages displaced by 120°, or 1/3 cycle. It is used for the distribution of high power electricity (all national electricity distribution networks distribute 3 phase electricity) and is particularly suited to high power loads.
See Plated Through Hole.
Measured or specified percentage variation from nominal.
See DIN Rail.
A round magnetic core with a hole in the middle.
The range of combined regulation tolerances such as the effects of input voltage variation, output load variation, temperature variation, drift and other specified variables. It is expressed as a plus/minus percent from nominal. Also called accuracy limit.
A characteristic of a multiple-output power supply (PSU) that describes the changes in the voltage of one output with respect to changes in the voltage or load of another.
A safety feature for power supplies with adjustable outputs where the trigger point of the OVP tracks with the voltage setting of the output such that a slow change in the output voltage will adjust the OVP setting but a fast change above the OVP point will trigger the OVP.
A change in a given parameter, typically associated with input voltage or output loading.
A short term effect on the steady state condition of a circuit.
The time required for the output voltage of a power supply (PSU) to settle within specified output accuracy limits following a transient. See Overshoot for drawing.
Response of a circuit to a sudden change in an input or output quantity. See Overshoot for drawing.
The time between introducing a transient (such as additional load) is introduced and the time the measured parameter (such as output voltage) returns and remains within a specified amplitude range. See Overshoot drawing.
Solid state device which allows the current flow between two of its terminals depending on a smaller current (or voltage) applied to the third terminal. There are two main types of transistors, bipolar junction transistors and Field Effect Transistors.
A bi-directional silicon-controlled switch. It will conduct in both directions (from MT1 to MT2 or vice versa). See Silicon-Controlled Rectifiers (SCR)
Three conductors wound side by side on a magnetic core or bobbin in which all three conductors are wound in the same operation.
Actual power generated or consumed in a circuit.
Abbreviation for transistor-transistor logic.
Circuit containing capacitance, inductance and (optionally) resistance, connected in series or parallel, which when energised at a specific frequency known as its resonant frequency, an interchange of energy occurs between the coil and the capacitor.
The number of turns on the transformer primary winding divided by the number of turns on the secondary winding. A Step-Down Transformer has a turns ratio more than one while a Step-up Transformer has a turns ratio of less than one. Usually explicitly specified as input/output turns ratio.
Abbreviation for Technischer Uberwachungs-Verein