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9.15 - Service valve (option 92)
The unit can be equipped with optional service valves to
facilitate maintenance and repair operations.
If option 92 is ordered, each refrigerant circuit will be
supplied with shut-off valves on the compressor economiser,
discharge and suction lines.
ATTENTION: The compressor suction valve must be used
without pressure difference at the terminals. If there is a
pressure difference, leak-tightness at the valve may be lost
and the valve can even fail altogether.
Equal pressure
9.16 - Variable frequency drive
The 30XAV units are fitted with a variable frequency drive
that allows adjustment the capacity of the compressor by
varying the speed of the motor within the frequency range
of 27.5-60 Hz.
Variable speed is produced by generating a controlled voltage
waveform, on which both frequency and voltage are
adjustable (via Pulse Width Modulation).
The compressor start-up/stop and the frequency setpoint
(within the acceptable range) is managed through RS485
communication via LEN Protocol by the "Carrier Controller".
One of the other features of the "variable frequency drive"
is to ensure the safety stop function of the unit via HP
switches wired to the digital inputs. This safety function
follows the EN ISO 13849-1 standard in compliance with the
requirements of the directive of equipments under pressure
(DESP).
Содержание AquaForce 30XAV 1050
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