A-Z Glossary
AMBIENT TEMPERATURE
Temperature of the stationary air surrounding the device. Is usually measured ca. 10mm beside the device in operation.
BATTERY TYPES
Li-Ion = Lithium Ions
LiFePO4 = Lithium iron-phosphate
NiCd = Nickel Cadmium
NiMH = Nickel Metal hydride
Pb = Lead
CLASS B
Protection against electronic shock taking special account of the leakage current.
CLASS BF
Same as Class B, however, taking into account the so-called „F parts“, which can occasionally come into account with patients and are isolated from all other parts.
CLASS CF
Class with the highest level of protection.
CONTINUOUS SHORT-CIRCUIT PROOF
Continuous short-circuit proof means that a short circuit can be permanently active, without the output being damaged.
If the error is fixed, the output will once again function normally.
DT
Abbreviation for desktop.
EFFICIENCY
The efficiency is calculated from the ratio between power output and input and it is always remains lower that one.
EMS
Abbreviation for Electronic Manufacturing Services (Contract manufacturing).
EMC
Abbreviation for electromagnetic compatibility. EMC is the ability of an electrical appliance to operate satisfactorily in its electromagnetic environment without adversely affecting this environment, which may also contain other equipment. Power supply units should comply with at least two generic standards for EMC:
1. The interference transmission standards ( interferences which the power supply unit emits by cable or through the air) and
2. Immunity standard (protection against interferences from outside).
These generic standards encompass a number of further sub-norms which set limit values for each strand (e.g. certain types of interference). FRIWO power supplies meet these standards even tighter than required since we believe that the EMV of our devices should be as good as possible to guarantee a trouble-free service.
GPP
Abbreviation for Global Power Plug.
LEAKAGE CURRENT
A current that flows through the ground when a device is in operation. It flows above capacity and the insulation resistance of an operating circuit over the protective ground conductor of a device.
LED
Abbreviation for Light Emitting Diode.
LIFE EXPECTANCY
Operating life of a power supply. At the end of their life, power supply units are increasingly likely to fail because components are worn out.
MPP
Abbreviation for Multi Power Plug.
MTBF
MTBF stands for Mean Time Between Failures (Average time between two consecutive device failures).
The MTBF indicates when a device fails on average due to processing or component defects before signs of wear set in.
NTC
A temperature-resistant resistor with negative coefficient, whereby the resistance values greatly reduce with increasing temperature. Therefore it is also called a thermistor. It serves not only to measure temperature but also to limit the inrush currents of power supply units.
OF
Abbreviation for Open Frame.
OPERATING TEMPERATURE
The temperature range, which the temperature must not be exceed or fall below when an appliance in operation.
OVERVOLTAGE PROTECTION
A circuit in the power supply monitors the output voltage. If a certain preset limit is exceeded the power supply is deactivated.
POWER-LIMITED
Electronic overload protection which limits the maximum output current to a preset value.
PP
Abbreviation for Power Plug.
SHORT CIRCUIT PROOF
Short circuit proof means that a temporary short circuit of some can be absorbed without any damages.
SINGLE RANGE
Power supplies with input voltage for usage in the corresponding countries.
SMD
Abbreviation for Surface-Mount Device.
SMT
SMT (surface-mount technology) is a technology, whereby the surface-mount devices (devices without wire leads) are directly soldered onto the PCB by means of solderable pads.
STANDBY LOSSES
Power requirements of a power supply in idle mode.
STORAGE TEMPERATURE
Temperature range in which a device may be stored (not operated) without causing damage.
THT
Stands for the English term through-hole technology and describes through-hole mounting. In this type of mounting, the components have wire leads (“wired components”) and are pushed through the PCB using contact holes in order to connect them through special THT-soldering processes afterwards.
UP
Abbreviation for flush mounting.
German (UnterPutzmontage)
USB
Abbreviation for Universal Serial Bus.
VOLTAGE CONTROL
A control loop in the power supply unit keeps the output voltage constant, regardless of all factors. (e.g. temperature)
WIDE RANGE
Wide range power supplies can be operated at different nominal/rated voltages without having tobe readjusted (manually or automatically) by a switch.