AERMEC NRB 0282 Series, Руководство по установке и обслуживанию

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48
COMMISSIONING - WARNINGS
Please note that, on request by the Aermec customer or the legi�mate
owner of the machine, the units in this series can be started up by the
AERMEC A�er-Sales Service in your area (valid only on ITALIAN territory).
The start of opera�on must be scheduled in advance based on the �me
frame for the comple�on of works for the system. Prior to the interven�on,
all other works (electrical and hydraulic hook-ups, priming and bleeding of
air from the system) must have been completed.
START-UP
OPERATIONS TO BE PERFORMED WITH NO VOLTAGE PRESENT
ATTENTION
the unit is not working:
Check:
- All safety condi�ons have been respected
- The unit is correctly fixed to the support surface
- The minimum technical spaces have been respected
- That the main power supply cables have appropriate cross-sec�on,
which can support the total consump�on of the unit. (see electric data
sec�ons) and that the unit has been duly connected to the ground.
- That all the electrical connec�ons have been made correctly and all the
terminals adequately �ghtened.
OPERATIONS TO BE PERFORMED WITH THE UNIT LIVE
ATTENTION
the unit is still not working:
- Supply power to the unit by turning the master switch to the ON
posi�on.
- Use a tester to verify that the value of the power supply voltage to the
phases is equal to 400V ± 10%; also verify that the unbalance between
phases is no greater than 3%.
- Check that the connec�ons made by the installer are in compliance with
the documenta�on.
- Verify that the resistor of the compressor sump is working by measuring
the increase in temperature of the oil pan. The resistance/s must
func�on for at least 12 hours before start-up of the compressor and in
any event, the temperature of the oil pan must be 10-15°C higher than
room temperature.
HYDRAULIC CIRCUIT CONTROLS
- Check that all hydraulic connec�ons are made correctly, that the plate
indica�ons are complied with and that a mechanical filter has been
installed in each inlet heat exchanger. (Mandatory component for
warranty to be valid).
- Make sure that the circula�on pump/s is opera�ng and that the water
flow rate is sufficient to close the contact of the flow switch, if installed.
- Check the water flow rate, measuring the pressure difference between
inlet and outlet of the evaporator and calculate the flow rate using the
evaporator pressure drop tables present in this manual.
- Check the correct func�oning of the flow meters if installed. Closing the
cut-off valve at the output of the heat exchanger; the unit control panel
must show the block. Finally re-open the valve and rearm the block
COMMISSIONING
- Once all the aforemen�oned checks have been carried out, the unit can
be commissioned
- Close the door of the electrical panel.
- Set the unit main switch to ON, the unit will start a�er a few minutes
OPERATIONS TO BE PERFORMED WITH MACHINE ON
ATTENTION
the unit is working:
Check:
- That the compressor input current is lower than the maximum indicated
in the electrical data table.
- Before star�ng the unit, check that the compressor rotates in the
correct direc�on through a three-phase protec�on. The spiral
compressors compress in one direc�on of rota�on only. Therefore, it
is essen�al for the phase of the three-phase spiral compressors to be
correctly connected (the correct direc�on of rota�on can be controlled
when the pressure on the intake side decreases and that on the flow
side increases with the compressor in opera�on). If the connec�on is
incorrect, the direc�on of rota�on is reversed: this causes a loud noise
and the reduc�on of current consump�on. In this case, the protec�on
system inside the compressor ac�vated turning off the unit. To solve the
problem, disconnect and swap the wires between two of the phases,
then connect the three-phases again.
- That the voltage value lies within the pre-fixed limits and that unbalance
between the three phases (three-phase power supply) is not above 3%.
- If having to take measurements and perform checks that require the
machine to run, you must:
- make sure that any remote control systems are disconnected; however,
keep in mind that the PLC on the machine controls its func�ons and can
enable and disable the components crea�ng hazardous situa�ons (e.g.
power and rotate the fans and their mechanical drive systems).
- Operate with the electrical board open the shortest �me possible
- Close the electrical board as soon as the single measurement or control
is performed
ATTENTION
The anti-freeze set temperature can only be varied by an authorised after-
sales centre and only after having checked that there is a suitable % of
anti-freeze solution in the water circuit.
Whenever this alarm intervenes, call the nearest authorised after-sales
service immediately
- Control of the water flow rate alarm, the unit provides for the
management of a flow rate alarm controlled by a differen�al pressure
switch or flow switch if provided. This type of safety device intervenes
a�er the first 30 seconds of pump func�oning, if the water flow rate
is not sufficient. The interven�on stops the compressor and the pump
itself.
COMMISSIONING - WARNINGS