Hamworthy QAA73.210, Инструкция по установке, наладке и обслуживанию

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HAMWORTHY HEATING LTD QAA73.210
Programmable Room Unit
500001305/B
4.8 Functions
Introduction
The functions described below require no settings. They are performed automatically but have an impact on the
plant.
For the rectification of faults, planning and plant maintenance, it may therefore be very advantageous to know
about their impact on plant operation.
Types of compensation:
The room unit offers 3 types of compensation each of which generates the effective flow temperature setpoint in a
different way. They are the following:
•
Weather compensation
•
Weather compensation with room influence
•
Room compensation
•
Fix flow temperature setpoint
4.8.1 Weather compensation
With this type of compensation, the building ’ s heat losses are compensated by an adequate flow temperature.
The colder the weather, the quicker the building cools down and the greater the heating circuit ’ s heat demand.
With this type of compensation, it must be ensured that the heating curve is correctly set, because the room unit
gets no feedback from the space whether the amount of heat supplied meets the demand of the users.
Note: The room influence (AMBON) must be set to "OFF" and, in addition, an outside sensor must be connected.
4.8.2 Weather compensation with room influence
Compared to pure weather compensation, this type of compensation offers enhanced comfort because with the
room influence, the room unit gets a feedback from the space.
Note: The room influence (AMBON) must be activated for the required heating circuits and, in addition, an outside
sensor must be connected.
Room influence:
The room influence acts on the room temperature setpoint. The deviation of setpoint / actual value of the room
temperature is multiplied by the correction factor KORR/2 and added to the deviation from the room temperature
setpoint in the opposite direction.
Room influence acts:
•
In the case of deviations of setpoint / actual value of the room temperature
•
With automatic or manual changeover to a higher or lower room temperature setpoint
4.8.3 Room Compensation
With pure room compensation, a PID control algorithm is activated. This is the preferred control mode if the room
temperature is the only compensating variable available. The selected control algorithm gives consideration to
both the actual value of the room temperature and the current slope (gradient). The P - part is generated by the
control deviation, the D - part from the gradient of the room temperature. The I - part suppresses continuous devia-
tions of setpoint / actual value.
Note: The room influence (AMBON) must be activated for the required heating circuits and, in addition, no outside
sensor may be connected.
The flow temperature and thus the room temperature are controlled as a function of the actual room temperature
and its current development. For example, if the room temperature rises slightly, the flow temperature will immedi-
ately be reduced even if there is deviation of setpoint / actual value apparent yet. To prevent continuous devia-
tions, the I - part of PID control keeps the room temperature at the required level.
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