ECKELMANN VS 3015 C, Инструкция по эксплуатации

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Compressor switching times for compressor step regulation
Compressor switching only occurs if the control error has exceeded a specified value (Dead band) and a
specific time for loading or unloading has elapsed. With compressor combined control, the lead time has no
influence on the enable of the FC compressor.
The switching time is calculated from the sum of a basic time t
b
and a variable time t
v
.
The variable time is inversely proportional to the control error. The higher the control error the shorter the delay.
In the case of maximum control error, the variable time t
v
= 0. In the case of declining control error, the time t
v
is
automatically increased up to the specified maximum time. The basic time and the maximum variable time for
the shifting up (switching on) and shifting down (switching off) can be configured as parameters for each
capacity stage.
In the case of combined control, the speed control is not enabled until after expiry of the basic time of the first
compressor capacity stage. The speed-controlled compressor is operated with the lowest speed until expiry of
the basic time.
The switch-on and switch-off delay only starts outside the neutral zone. A compressor stage is activated with
the delay time for number of running compr 1. For step control, switching down always begins with the
delay of the first stage; for combined control, the deactivation times are directly assigned to the compressor
stages.
5.4.3 Control algorithm with LP combined control
Depending on the low-pressure control error, a correcting variable is calculated which controls the speed of the
compressor as a 0-10 V signal.
If all compressor stages are switched off and the actual value is greater than the setpoint (positive control
error), the first compressor stage (C1: Release of frequency converter) is switched on immediately. The speed
control is not activated until after expiry of a delay time (time = Basic time ON V1 - see also menu 3-2-4-a). The
compressor is operated with a configurable minimum speed during the time delay.
The compressor speed can also be specified manually (parameter Man. op. menu 3-2-1-1). If "---" is entered,
the signal is determined via the controller. The manual mode is only used for test and service purposes. The
number of running compressor stages remains constant in manual mode. No FC base load rotation is
performed.