rated capacity
The nominal output is the ("named") output of a device, a system, including an electrical consumer or another energy converter ( generator , hydraulic motor , heat engine ) specified by the manufacturer , which can convert (absorb) or generate (output) it.
The nominal output of a system for generating electricity is the continuous output for which it is ordered in accordance with the delivery agreements (Germany: StromStG). The continuous output of a system is the highest output that can be achieved with normal operation without time restrictions and that does not affect its service life and safety. If the nominal output cannot be clearly determined according to the order documents, a one-off performance value that can be achieved under normal conditions in accordance with the technical standards for acceptance measurements must be determined for a new system. In the case of combined heat and power plants, the nominal power is the nominal electrical power.
The nominal power is binding for the entire service life of the system. Changes to the nominal output are only permitted in the event of significant changes in the nominal conditions and structural measures on the system. The nominal output of a system must not be adapted to a temporary change in output. In addition, no changes to the nominal power may be made in the event of power reductions as a result or to avoid damage or due to aging, wear and tear or contamination. Likewise, a seal on the power regulator as a limitation of the power output has no effect on the rated power.
The operator of the system must provide evidence of a reduction in the nominal output by means of suitable documents (for example: expert reports, official instructions) to the main customs office.
Usually the maximum power that can be achieved in continuous operation is specified as the nominal power. For devices that are only suitable or designed for short-term operation (e.g. soldering guns, hand drills, hand blenders), however, the current or maximum power is often specified. This may only be called up using the short operating time (KB time) specified on the nameplate in the form of "KB xx min".
There is no uniform stipulation whether the nominal power is the power consumed or the power delivered. However, a distinction can be made between device and system types in which the power consumed or output is usually specified as the nominal power. In the first case, the term "power consumption" has been established to identify the device:
- The nominal power specification usually indicates the power consumed:
The power delivered by the device is lower by the degree of efficiency .
Examples are vacuum cleaners , electrical hand and kitchen appliances, etc. In hand drilling machines , the maximum electrical power consumed when the drill chuck is at a standstill is often specified.
For loudspeakers and loudspeaker boxes , the designation nominal power for the maximum permissible continuous power consumption when fed with a pink noise according to DIN 45324 has become established. - The nominal power specification usually indicates the output :
Among other things, for motors , gearboxes , power plants , transformers , generators (including automotive alternators and bicycle dynamos ) and inverters , the electrical or mechanical power output is given as the nominal output.
In the case of photovoltaic systems , the electrical power output is specified under standardized test conditions ( irradiance 1000 W / m², module temperature 25 ° C). Often this is indicated by the indication " Watt Peak ".
In the case of heaters and other heat generators, the maximum heat output (heat output) that can be achieved in continuous operation is specified as the nominal heat output .
The nominal power of radio transmitters is the power of the high-frequency signal at the output when the nominal impedance is connected (usually 50 Ohm, 60 Ohm or 75 Ohm).
In the case of audio amplifiers , the maximum electrical power that can be supplied in a defined load impedance (usually 2 ... 8 ohms) when fed with pink noise according to DIN 45324 has established itself as the nominal output . The PMPO specification , on the other hand, denotes the peak power that can only be delivered in the millisecond range without the amplifier being damaged. It is largely irrelevant for the assessment of music reproduction. The nominal power of audio amplifiers was previously given in the form of the sinus power and the so-called music power . They indicated the continuous output with a continuous tone or the short-term maximum controllability at the loudspeaker nominal impedance.
In the case of rocket and jet turbine engines , the thrust is specified instead of a power, i.e. the power developed by them under certain conditions.
In the case of the turbines or gasoline engines driving the propellers , however, the mechanical power output on the shaft is specified as the nominal power.