Millipore NovAseptic GMP ATEX, Инструкция по установке и эксплуатации

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NovAseptic GMP ATEX Mixer Installation and User Guide 25
Variable-Frequency Drive
A variable-frequency, adjustable-speed drive (VFD) controls the rotational
speed of an alternating current (AC) electric motor by controlling the
frequency of the electrical power supplied to the motor. VFDs are also
known as adjustable-frequency drives (AFD), variable speed drives (VSD),
AC drives and inverter drives.
When starting a motor, a VFD initially applies a low frequency and voltage
to the motor. A VFD increases the applied frequency and voltage at a
controlled rate and accelerates the load without drawing excessive current.
Notes:
•
Consult the parameter settings, circuit and terminal diagrams before
installing the control cabinet.
•
Validate the process conditions. If the production conditions are altered
after commissioning of the mixer the process may required revalidation.
•
Validate the possible minimum & maximum operating speed for each
process.
•
Set VFD unit to 100% nominal power (kW) and current (A) of the motor
rating.
•
Prevent excess speed & acceleration. It may cause decoupling of mixer..
•
Electric motors, VFDs and associated components are capable of
creating a spark when not used properly in an atmosphere containing
flammable solvents and gases. Consider this when selecting parts for a
system used in ATEX environment.
Warning:
Motors installed on NovAseptic Mixers are rated to operate from 5 to 50 Hz. The
motor speed specifications may be found in data sheet SP1185EN00.
The motor may not be operated at lower than 5 Hz. If less than 5 Hz is select the
VFD should be set to output 0 Hz and the motor stops. (This is the default condition
for VFD’s supplied by Millipore.)
If the motor is to run at lower than 15 Hz the motor for an extended time it will become
warm. If the thermal protection is wired into the stop circuit the motor may shut down if operated for
too long a period of time at low speed.
If the motor is to be operated continuously below 15 Hz, contact Millipore Technical Service
for
recommendations on how to keeping the motor sufficiently cool for your application.