Carel Heos, User Manual

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34
ENG
Heos +0300078EN - rel. 1.6 - 23.11.2017
Below is the control diagram based on condensing temperature; the
same also applies when using the diff erential between water inlet and
outlet temperature.
Output
100%
Setpoint
Temp. cond.
or Temp. water
Diff.
Fig. 6.af
Note : on screens Bab01-07 for selecting the analogue outputs, the
minimum and maximum values can be set for the output voltage. For
example, to select the 2-10 Vdc standard, simply set the minimum voltage
to 2V.
Screen Daa07 is used to select the type of control (condensing
temperature or water inlet/outlet temperature or diff erential), the
corresponding set point, diff erential and integral time.
If control is selected based on water temperature, screen Daa10 is
displayed for setting a maximum safety threshold for the condensing
temperature/ pressure.
Par. Description Def UoM Min Max
co3 Type of water-cooled condenser control
0: COND. TEMP.
1: W OUTIN TEMP.
2: W OUT TEMP.
3: W IN TEMP. 0 0 3
co4 Condensing temp. set point 20.0
(68.0) °C
(°F) 10.0
(50.0) 55.0
(131.0)
Condenser water temp. diff . set point 5.0
(9.0) °C
(°F) 0.1
(0.18) 20.0
(36.0)
co5 Cond. control proportional coeffi cient 40 %/°C 1 999
co6 Cond. control integral time 100 s 0 999
coA Cond. control safety set point 42.0
(107.6) °C
(°F) 30.0
(86.0) 55.0
(131.0)
cob Cond. control safety diff erential 5.0
(9.0) °C
(°F) 0.0
(0.0) 9.9
(17.8)
At compressor start-up, in order to improve the response of the
condensing stage control valve, parameters can be set (screens Daa08
and Daa13) to allow pre-opening.
Air-cooled condenser
Below is the air-cooled condenser connection diagram. In this case,
air fl ow-rate is modulated by controlling the fan (0-10 Vdc or by
digital output, set in the I/O confi guration menu) so as to stabilise the
condensing temperature.
0...10 V
T
cond
Cooled GAS Hot GAS
Fig. 6.ag
Below is the control diagram based on condensing temperature/
pressure.
Fan Speed
100%
Setpoint
Temp. cond. Diff.
Fig. 6.ah
Par. Description Def UoM Min
Max
co4 Condensing temp. set point 20.0
(68.0) °C
(°F) 10.0
(50.0) 55.0
(131.0)
co5 Cond. control proportional coeffi cient 40 %/°C 1 999
co6 Cond. control integral time 100 s 0 999
6.13 Anti-sweat on inverter with cold plate
If the inverter is water-cooled, condensation may form when the water
temperature is lower than the dew point in the environment where the
inverter is installed. This may potentially occur on low temperature units,
when the cooling water is normally lower than room temperature.
There are basically two types of connection for inverter cooling circuits:
•
Parallel connection to the condenser
•
Serial connection to the condenser
Parallel connection
Below is the inverter water connection diagram. In this case, there is an
on/off valve controlled based on the temperature read near the inverter’s
microprocessor. The set point and corresponding diff erential (fi xed at
1 °C) must be set, keeping in consideration that the cooler parts of the
board are below the controlled temperature and depend on the type of
heat exchanger used to cool the inverter.
T
cond
ON/OFF
M
Fig. 6.ai
The on/off valve is selected in confi guration branch Bad13, while the
parameters are set on screen Dad06, used to select a minimum operating
temperature threshold for the valve, below which the valve closes.
Note : If a digital output is selected (Bad13), the confi guration is
automatically set to “Parallel connection”, while if the other confi guration
is required, no output must be selected for Bad13.