Special case:
If cooling sequence 4+5 is enabled, minimum limitation can be set lower by an
adjustable value (LIMCOOL).
Cooling sequence 4+5
active
This feature prevents the refrigeration machine from switching off again shortly
after switching on in case of multistage (DX) cooling.
This function is only active if the main controlled variable and the input for general
limitation have the unit °C.
The following applies to relative limitation:
Relative limitation
•
You can only activate maximum and minimum differential limitation (LIM DHI,
LIM DLO) if the main controlled variable and the limit sensor are configured with
the same physical unit
•
The adjusted limit setpoints refer to the temperature difference between the
main controlled variable and the limit sensor
•
You can enter one setpoint each for maximum and minimum differential
temperature limitation
Supply air temperature limitation for a displacement ventilation outlet:
Application example
1,
5 m
w
w
x
x
T
T
x
w
[
LIM DHI
]
[
LIM DLO
]
Limitation max
Limitation min
31
01
S
34
en
Acts an all sequences
!! Not meaningful with cascade control !!
Setpoint adjustment
9.6.3
Info pages
With controller 1, type A, “General limitation“ is also displayed on an Info page. The
value displayed at right is not the setpoint, but the limit value currently active.
This Info page shows 23.4 °C as the actual value of the supply air temperature at
left, and the relevant limit temperature of 35 °C at right.
SET
122 / 174
Siemens
Universal Controllers RLU2…
CE1P3101en
Building Technologies
Controller (CTLOOP x)
29.08.2008