Adapting The Control Algorithms - Gira 5142 00 Product Documentation

4.2.4.2.3 Adapting the control algorithms

Adapting the PI control
There are several systems available, which may heat or cool a room. One option is to uniformly
heat or cool the surroundings via heat transfer media (preferably water or oil) in connection with
room air convection. Such systems are used, for example, with wall mounted heaters,
underfloor heating or cooling ceilings.
Alternatively or additionally forced air systems may heat or cool rooms. In most cases such
systems are electrical forced hot air systems, forced cool air systems or refrigerating
compressors with fan. Due to the direct heating of the room air such heating and cooling
systems work quite swiftly.
The control parameters need to be adjusted so that the PI control algorithm may efficiently
control all common heating and cooling systems thus making the room temperature control
work as fast as possible and without deviation. Certain factors can be adjusted with a PI control
that can influence the control behaviour quite significantly at times. For this reason, the room
temperature controller can be set to predefined 'experience values' for the most common
heating and cooling systems. In case the selection of a corresponding heating or cooling system
does not yield a satisfactory result with the default values, the adaptation can optionally be
optimised using control parameters.
Predefined control parameters for the heating or cooling level and, if applicable, also for the
additional levels and the second control circuit are adjusted via the "Type of heating" or "Type of
cooling" parameters. These fixed values correspond to the practical values of a properly
planned and executed air conditioning system and will result in an ideal behaviour of the
temperature control. The heating and cooling types shown in the following tables can be
specified for heating and cooling operation.
Type of heating
Heat water
heating
Underfloor heating
Electrical heating
Fan coil unit
Split unit (split
climate control unit)
Table 2: Predefined control parameters and recommend control types for heating systems
Cooling type
Cooling ceiling
Fan coil unit
Split unit (split
climate control unit)
Table 3: Predefined control parameters and recommend control types for cooling systems
If the "Type of heating" or "Type of cooling" parameters are set to "Via control parameters" it will
be possible to adjust the control parameter manually. The feedback control may be
considerably influenced by presetting the proportional range for heating or for cooling (P
component) and the reset time for heating or for cooling (I component).
Order No. 5142 00
Order No. 5145 00
Proportional Reset time
range (preset) (preset)
5 Kelvin 150
minutes
5 Kelvin 240
minutes
4 Kelvin 100
minutes
4 Kelvin 90 minutes Continuous
4 Kelvin 90 minutes PWM
Proportional Reset time
range (preset) (preset)
5 Kelvin 240
minutes
4 Kelvin 90 minutes Continuous
4 Kelvin 90 minutes PWM
Software "Push button sensor 3 plus"
Functional description
Recommended Recommended
PI control type PWM cycle time
Continuous / PWM 15 min.
PWM 15-20 min.
PWM 10-15 min.
---
10-15 min.
Recommended Recommended
PI control type PWM cycle time
PWM 15-20 min.
---
10-15 min.
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