Loading ...
Sorry, an error occurred while loading the content.

Re: soft starters vs variable speed drives

Expand Messages
  • girez
    ... Now on the other hand if the VFD is just there for bell and whistles then simply disconnect it from the motor and bypass it totally, connecting your new
    Message 1 of 4 , Nov 1, 2009
    View Source
    • 0 Attachment
      --- In ElecMotorControl@yahoogroups.com, "James" <blackrider200936@...> wrote:
      >
      >
      >
      > --- In ElecMotorControl@yahoogroups.com, wahyu pamungkas <wahyu.wpdsb@> wrote:
      > >
      > > Then how it works? when Softstarter (voltage control) is installed upstream
      > > the VSD, the VSD will got undervoltage. If VSD is upstream the softstarter
      > > then the softstarter supply is sub-standard.
      > >
      > > On Tue, Sep 29, 2009 at 1:55 PM, bonner_nj@ <
      > > bonner_nj@> wrote:
      > >
      > > >
      > > >
      > > > Hi people am a new member in this forum but i find it prudent fr me to join
      > > > people on the same line of my career so that we can share what we know.
      > > > Now my first question is . is it possible for someone to connect a soft
      > > > starter on a compressor that already has a VSD?note that the VSD is not a
      > > > foreign gadget that means that it is inbuilt with the compressor from the
      > > > manufactures.
      > > >
      > > > I would appreciate your contribution
      > > > Regards Bonni.
      > > >
      > > >
      > > >
      > >
      > >
      > > [Non-text portions of this message have been removed]
      >
      >
      > I think it is possible, try to see the manual of Atlas copco compressors if you can search through the net. We have compressor here in the company that is with soft starter, the circuit is quite complicated, motor control concept is applied. The circuit contents contactors and relays before it will be connected to the vsd circuit.
      > Our compressor is 50 hp Atlas Copco brand. thanks!
      > >
      > First of all why did the mfgr install a VFD on his compressor? Its because he is trying to employ softstarting initially and maybe modulate the speed and torque as the pressure reaches setpoint? If this is the case and you still think you need more softstarting that is currently available, then you should enquire about reprogramming the VFD to RAMP UP A LITTLE SLOWER this will give you the softstarting that you may be looking for.
      Now on the other hand if the VFD is just there for "bell and whistles" then simply disconnect it from the motor and bypass it totally, connecting your new soft starter with ramp up performance to match your compressor.

      Take care.
    Your message has been successfully submitted and would be delivered to recipients shortly.