English
3/8
Hyperchiller 450-760
Th
e specifi c weight values at diff erent temperatures for glycol percent-
age values are given in the table.
%
glicol
Temperature [°C]
-10
0
10
20
30
40
50
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.
3.5 Electrical circuit
3.5.1
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 power supply must be symmetrical (the eff ective voltages and
the phase angles of consecutive phases must be equal). Th
e maxi-
mum permissible voltage imbalance is 2%.
Connection
1) Th
e electrical power supply must be connected to the chiller using a
4-wire cable, comprising 3 phase conductors and an earth conductor,
with no neutral. For minimum cable section, see par. 7.2.
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
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!
3.5.2 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.
3.5.3 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.
3.5.4
Rotation direction of the motors
Aft er starting the unit, motor rotation direction can be checked; the
check must be carried out on the fans, making sure rotation occurs in
the direction of the arrow stamped on them.
If not, swap over two of the phase wires of the power supply.
