ECKELMANN VS 3000 User Manual

Version 2.02 15.05.2007 Function of VS 3000
30
Basic time and maximum variable time for switching forward (on) and back (off) are definable as parameters for each
loading/unloading of a condenser stage. The following relationships apply for determining control times:
t = t
b
+ t
v
t
b
= Definable
The following applies for t
v
:
t
v
= t
v_max
−

t
v_max
⋅ d
t

d
t_max
The following applies:
d
t
>d
t_max
d
t
=d
t_max
t
v
= Variable control time
t
v_max
= Max. control time (definable for each stage)
d
t
= Control error
d
t_max
= Max. control error (definable)
Control time is calculated at every controller run. The variable time is calculated anew and the time elapsed
since the last control time is compared w ith the calculated time. If the calculated control time is smaller than or
equal to the elapsed time, fan actuation takes place w hen the control error is greater than the specified neutral
zone.
The following diagram shows calculation of the control time:
ZNR. 51203 65 330 E0
Control error dt [°C]
Run time [s]
VS 3000 Condenser fan run times
0
2
4
6
dt
8
10
dt max
12
0
20
40
60
80
100
120
140
120
160
180
200
220
240
t
v max
Basic time t
b
Run time t = t + t
b
t+t
v maxbv
t
b
t
v
When high pressure is controlled by step controller, the number of fan stages running is output via the Fan
Speed analog output according to the following equation:
U
OFF
=
(
No of compressor stages running ⋅ 10V
)
(
No of compressor stages defined
)

ECKELMANN VS 3000 Specifications

General

Brand	ECKELMANN
Model	VS 3000
Category	Controller
Language	English