Function of VS 300
48
Doku-Version 2.05 - Firmware 2.10 - 15. September 2017
4.5.3
Control algorithm for high-pressure control
The controller cycle time is 1 second. The control algorithm varies with the control type.
In the wet vapor range, temperature is a distinct function of refrigerant and pressure:
t = f (p, refrigerant). The VS 300 makes calculation from the pressures measured as a function
of the given refrigerant temperatures. Exclusively temperature values are used for control.
Temperatures (t
0
, t
c
) listed in the documentation therefore substitute for pressures (p
0
, p
c
).
4.5.4
Control algorithm with step controller
High pressure detected by an A/D converter is compared with the setpoint (see section 4.5.10 Determining the
High-pressure Setpoint). The following relationship applies:
Control
error
With a
positive
control error (t
c_Act
> t
c_Setp
+ 0.5 x Neutral Zone) and rising pressure, the step controller moves
forward one step. This means that one additional condenser capacity stage is enabled. With a positive control
error and falling pressure, no capacity stage is loaded in anticipation of pressure reaching the neutral zone in a
short time.
With a
negative
control error (t
c_Act
> t
c_Setp
- 0.5 x Neutral Zone) and falling pressure, the step controller
moves back one step. This means that one additional condenser capacity stage is disabled. With a negative
control error and rising pressure, no capacity stage is unloaded in anticipation of pressure reaching the neutral
zone in a short time.
C1
T
ime
ZNR
.
51203
6
5
030
E1
Starts monitoring
C2
C3
Start time de
l
ay
= 6
Min
.
Off time
Start time de
l
ay
= 6
Min
.
Off time
Start time de
l
ay
= 6
Min
.
No off time
Содержание VS 300
Страница 8: ...vi Doku Version 2 05 Firmware 2 10 15 September 2017 Notice ...
Страница 18: ...System Design of VS 300 10 Doku Version 2 05 Firmware 2 10 15 September 2017 Notice ...
Страница 22: ...Application of VS 300 14 Doku Version 2 05 Firmware 2 10 15 September 2017 Notice ...
Страница 158: ...Parameter List and Menu Structure of VS 300 150 Doku Version 2 05 Firmware 2 10 15 September 2017 Notice ...
Страница 160: ...Decommissioning and disposal 152 Doku Version 2 05 Firmware 2 10 15 September 2017 Notice ...
Страница 166: ...Alarms and Messages of VS 300 158 Doku Version 2 05 Firmware 2 10 15 September 2017 Notice ...
Страница 170: ...162 Doku Version 2 05 Firmware 2 10 15 September 2017 Notice ...
Страница 172: ...Order No s and accessories of VS 300 164 Doku Version 2 05 Firmware 2 10 15 September 2017 Notice ...