where
Vtot= vol. circuit total (in litres)
P t min/max= specifi c weight at the minimum/maximum temperature
reached by the water [kg/dm3].
Th e specifi c weight values at diff erent temperatures for glycol percent-
age values are given in the table.
%
Temperature [°C]
glicol
-10
0
10
20
0%
1.0024 1.0008 0.9988 0.9964 0.9936 0.9905 0.9869
10%
1.0177 1.0155 1.0130 1.0101 1.0067 1.0030 0.9989
20%
1.0330 1.0303 1.0272 1.0237 1.0199 1.0156 1.0110
30%
1.0483 1.0450 1.0414 1.0374 1.0330 1.0282 1.0230
!
Caution: When fi lling the system, take into account the capac-
ity of the expansion vessel as well.
3.4 Electrical circuit
3.4.1
Checks and connections
!
Before carrying out any operation on the electrical system, make
sure that the appliance is disconnected from the electrical power sup-
ply.
All electrical connections must comply with the applicable regulations
in force in the country of installation.
Initial checks
1) Th e power supply voltage and frequency must correspond to the
values stamped on the chiller nameplate. Th e power supply charac-
teristics must not deviate, even for brief periods, from the tolerance
limits indicated on the electrical diagram , which are +/- 10% for the
voltage; +/- 1% for the frequency.
2) Th e voltage must be supplied with phase and neutral conductors,
and the latter must be connected to earth in its own cabin (TN
system, or behalf of the supply company, TT system). Th e phase
conductor and the neutral conductor are not interchangeable and
must not be confused.
3) A diff erential thermal-magnetic switch suitable for the absorp-
tion specifi ed on the data plate, with contact gap enabling complete
disconnection in category III overvoltage conditions and complying
with the regulations in force, must be installed between the power
cable and the electric line. For the correct sizing of the switch, refer
to the absorbed current specifi ed on the appliance data plate. Th e
chosen device must be lockable in the open position in case of
maintenance.
Collegamento
1) Th e electrical power supply must be connected to the chiller using a
3-wire cable, comprising 2 phase conductors and an earth conductor.
For minimum cable section, see par. 7.3.
English
2) Pass the cable through the cable entry on the rear panel of the ma-
chine and connect the phase and neutral to the terminals of the main
isolator switch (QS); connect the earth wire to the earth terminal
(PE)..
3) Ensure that supply cable has at its source protection against direct
contact of at least IP2X or IPXXB.
4) On the supply line to the chiller, install a residual-current circuit
breaker with a trip rating of (RCCB - IDn = 0.3A), with the current
30
40
50
rating indicated in the reference electrical diagram, and with a short
circuit current rating appropriate to the short circuit fault current
existing in the machine installation area.
Th e nominal current In of the magnetic circuit breaker must be
equal to the FLA with an intervention curve type D.
5) Max. grid impedance value = 0.274 ohm.
Subsequent checks
Check that the machine and the auxiliary equipment are earthed and
protected against short circuit and/or overload.
!
Once the unit has been connected and the upstream main switch
closed (thereby connecting the power supply to the machine), the
voltage in the electrical circuit will reach dangerous levels. Maximum
caution is required!
3.4.2
General alarm
All the chillers are equipped with an alarm signalling system (see
electrical diagram), comprised of a switching free contact in a terminal
block: this may be used for the connection of an external audible or
visual alarm, or used to provide an input signal for a logic control
system such as a PLC.
3.4.3
ON/OFF remoto
All the chillers can be connected to a remote ON/OFF control.
See the electrical diagram for the connection of the remote ON-OFF
contact.
ICEP003-005 (60Hz)
3 / 8