Frequency Initial Setting; P Control; I Control; Limit Of Frequency Variation Width - Daikin Altherma EKHBH Series Service Manual

ESIE06-03
Indoor frequency The difference between the outlet water temperature and the temperature set by the remote controller
command (∆D will be taken as the "∆D signal" and is used for frequency command.
signal)
Frequency initial When starting the compressor, or when conditions are varied due to the change of the room, the
frequency must be initialized according to the total of a maximum ∆D value of the hydro-box and the
setting
Q value of the hydro-box.
Q value: hydro-box output determined from hydro-box.
PI Control
(determine
frequency up/down
by ∆D signal)
Part 2 – Functional Description

P control

Calculate ∆D value in each sampling time (20 seconds), and adjust the frequency according to its
difference from the frequency previously calculated.

I control

If the operating frequency is not change more than a certain fixed time, adjust the frequency up
and down according to the ∆D value, obtaining the fixed ∆D value.
When the ∆D value is small...lower the frequency.
When the ∆D value is large...increase the frequency.

Limit of frequency variation width

When the difference between input current and input current drooping value is less than 1.5 A, the
frequency increase width must be limited.
Frequency management when other controls are functioning
When frequency is drooping;
Frequency management is carried out only when the frequency droops.
For limiting lower limit
Frequency management is carried out only when the frequency rises.
Upper and lower limit of frequency by PI control
The frequency upper and lower limits are set depending on hydro-box.
When outdoor unit low noise or quiet commands come from hydro-box, the upper limit frequency
must be lowered than the usual setting.
Outdoor Unit Functional Concept
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2
3
4
5
2–15