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NRR 2-52, NRR 2-53, URB 55 - Installation & Operating Manual -
850646-00
Specialist terms / Abbreviations
Here, we explain some abbreviations, specialist terms, etc., which are used in this Manual.
NRR .. / NRG .. / NRGT ... / URB ...
GESTRA equipment and type designations, see page 9.
PI controller
Controller with proportional (P) and integral (I) control.
SELV
Safety Extra Low Voltage
Control direction
The control direction indicates whether control is for supplying (positive) or draining (negative).
Pb (proportional band)
The proportional band enables the controller amplification to be adapted to suit the controlled system. For
further information, see page 59, guide to setting control parameters.
Ti (reset time)
The integral element ensures that control deviations can be fully corrected, with no remaining deviation.
For further information, see page 59, guide to setting control parameters.
Neutral zone
If the actual value reaches the (set point +/- of the neutral zone), the manipulated variable does
not change in this range, see page 59.
PI controller
Controller with proportional (P) and integral (I) control.
