Algorithm
a mathematical formula, a flow diagram or a program. In control technology : Algorithm is used to refer to procedures for defining mathematical operators, e.g. controller algorithms for a PID controller [...] Recursive algorithms that recalculate the estimated values during each step with the inclusion of a new measured value set while using information from the previous steps. They are most suitable for use
Error limits of a measuring instrument
limits are pre-defined essentially in relation to systematic deviations from the correct or agreed value of the measured variable . They are also not allowed to be exceeded by random deviations (DIN 1319) [...] calibration error limit, which states the largest permissible error in the new state, and the in-service error limit that is not allowed to be exceeded also during continuous usage (VDI 2600).
Operating mode of a control
from the system to be controlled. Here in accordance with DIN 19 237 a differentiation is made between six variants: automatic mode: Operating mode in which the control operates without intervention from [...] in which the sequence chain can be set to any step by the operator. inching mode: Operating mode for sequential control in which switching the sequence chain to the next step is dependent on the intervention [...] from the operator according to a program in a control sequence that is specifically started (automatic control). semi-automatic mode: Operating mode in which only part of the control or the program operates
Particle size
scoring to occur there. Much depends on how their size compares with the respective gap width: Particles which are much smaller than the gap to which they have gravitated will pass through without causing [...] removed prior to assembly. Particle sizes can vary greatly and their distribution – in terms of quantity – is not very even either ( Figure P 4 ). For example, smaller particle sizes tend to be more common [...] slightly smaller, they will tend to clog up the gap at a low flow velocity ( Figure P 5 a ). Particles about the same size as the gap cause the most damage, since they lead to jamming and scoring in the gap
Flange connection
diameters DN 13 to 127 for operating pressures from 25 to 350 bar and nominal diameters DN 13 to 51 for 400 bar operating pressure. The port dimensions correspond to the SAE flange according to SAEj 518, however [...] however for new designs metric screws are to be used. Flanges with this layout are very common in hydraulics and are used in suction and pressure lines. They are very space-saving to install. Square flange [...] thread and O-ring seal according to ISO 6184. Two series are standardised: Nominal diameters DN 10 to 63 for 250 bar operating pressure and nominal diameters DN 10 to 80 for 400 bar operating pressure
Adjustment of displacement machines
with ( Figure V 22 ). The term "feedback controlling" is only correctly applied to adjustment processes if it relates to output variables of displacement units ( pressure and flow rate in pumps and moments [...] the pump or motor is still subject to interference, e.g. leakage losses - and is therefore controlled. In practice, this method of observation does not correspond to the standard terms, but it is necessary [...] talk of "controls" which are actually "feedback controls" Equally "controlling" should not be equated to "adjusting", as this is a measure of the pump, which is necessary for controls and feedback controls
Frictional pressure
The differential pressure required to move a piston without an external load – i.e. to overcome the friction Differential pressure under defined conditions in the cylinder chamber.
Gas filling pressure
Gas pressure that is applied to a fluid vessel with or without separator. On hydraulic accumulators the gas filling pressure corresponds to the precharge pressure. Example: hydropneumatic accumulator
Holding current
Minimum current needed to flow in an electrical load circuit (e.g. in a solenoid or another electro-mechanical signal converter) in order for a valve to be held in the closed position by the electro-mechanical [...] electro-mechanical signal converter without detent.
Plug-in connection
Connection for hoses in accordance with DIN 20 043, which is quick to fit without the use of tools and can be detached.