Iii.1.11 Menu Default Reset - Hitecsa Advance EQS Serie Manual Del Usuario

An approach threshold of around 5K is set on the screen, a value that guarantees
the correct level of refrigerant in the evaporator.
If the approach calculated in the machine operating point is greater than the set
approach threshold, then the algorithm calculates a correction (negative) to the
subcooling set-point with a PID. The correction cancels out as the approach
returns to the value defined on the screen. Below the defined approach threshold,
the subcooling set-point is not modified.
Approach threshold above which the PID starts up to lower the subcooling
1
set-point.
Parameter that calculates the ideal set for low pressure.
2
Subcooling set-point in nominal and full load condition.
3
Minimum limit of the subcooling set-point that can be reached when the PID
4
is actuated for approach control, in case of approach over the threshold
defined in point 1.
Maximum limit of the subcooling set-point used only for compr. minimum
5
work frequency inverter, in case of approach above the threshold defined in
point 1.
On screen Jj89 and following, if there is a second circuit, the proportional,
integrative and derivative parameters of the PID algorithm are set, that modify the
subcooling set-point. If prevention is active, the integral time takes on the PID Ti
value (prev.).
III.1.10.3 EEV for LBV valve management (versions
with Turbocor compressor)
In the versions with Turbocor compressor, for each compressor, in addition to the
electronic valve that regulates the level of the refrigerant in the flooded exchanger,
there is also an LBV (Load Bypass Valve) which manages the gas bypass to the
compressor.
In masks Jj91 and later, if a second circuit is present, it is possible to set the
parameters that allow you to manage the gas bypass at the start of the
compressor to facilitate the transition phase, or to adjust under very low loads to
avoid switching off the last compressor of the machine.
Percentage of LBV opening at compressor start
1
Closing speed at the end of the compressor's Ramping Up stage
2
(expressed in percentage closing per second)
Maximum LBV valve opening when required by low load regulation
1
Maximum cavity temperature admitted for regulation
2
Maximum duration of low load regulation before closing the valve and
3
waiting for the compressor to switch off
Maximum overheating threshold for enabling regulation
4
USM_CONTROL EQS_2335a21275_208549_210701_ES-EN-FR-DE-IT
The regenerative recovery exchanger has the dual purpose of increasing the
compressor suction superheat and of increasing the subcooling at the inlet to the
electronic valve which regulates the level of the refrigerant in the flooded exchanger.
For this purpose an electronic thermostatic valve is used, which is controlled by a
PID algorithm to maintain on the circuit the required overheating set-point calculated
on the output of the regenerative recovery heat exchanger.
1
2
3
The overheating set-point that is used, however, is not fixed, but is calculated with
4
the following formula: SetSH = cost * (HPC – BPC). Where:
5
SetSH = overheating set
Cost = constant defined by the regulator in %. The default value is 66%.
HPC = high pressure converted into temperature, i.e. the conversion into
temperature of the pressure measured on the compressor's delivery line.
LPC = low pressure converted into temperature, i.e. the conversion into
temperature of the pressure measured on the compressor's intake line.
The proportionality coefficient to calculate the overheating set-point and the other
parameters necessary for the adjustment are set in screen Jj97 for circuit 1 and ji98
for circuit 2.
On screen Jj97 and following, if there is a second circuit, the proportional,
integrative and derivative parameters of the PID algorithm are set, that manages
EEV control for regenerative recovery heat exchanger management.

III.1.11 Menu default reset

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2
In the Reset default menu it is possible to reset all settings of the Service menu
back to original factory settings.
1
2 1
3
2
4
98
III.1.10.4 EEV for regenerative recovery heat exchanger
Proportionality coefficient for the overheating set-point calculation.
1
Minimum valve opening percentage
2
Maximum valve opening percentage in relation to level valve opening
3
Valve opening percentage during the pre-circulation stage
4
Select YES and confirm with Enter to start the reset.
Setting save date (coincides with the date the unit was first switched on).
CONTROL EQS
management
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