Page 2 of 2 FirstFirst 12
Results 14 to 16 of 16
  1. #14
    Join Date
    Aug 2012
    Location
    west burbs,il
    Posts
    177
    Post Likes
    Good point. Ah I thought I'd throw it out there . o thought about it the fact too.

  2. #15
    Join Date
    Aug 2015
    Location
    California
    Posts
    6
    Post Likes
    I've seen this in the past and it was a controls nightmare. Even with an abundance of protection the end user let the magic smoke out of three VFD's within the warranty period before the general made the call to just add 3 more VFD's and allow us controls guys to sequentially stage and ramp them to need. Although if the area being served wasn't critical as in my example case.. and the user wouldn't be bothered by downtime and what not then sure why not

  3. #16
    Join Date
    Jan 2008
    Location
    Phoenix Arizona
    Posts
    1,662
    Post Likes
    This is an old thread and not to sure why it was resurrected but one thing people are missing is VFD make different amounts of pulse width modulated DC that simulates AC, but at the end of the day the motors themselves are going to see FLA most of the time or a little less. A 460v 3 phase motor might see 30hz but it's at 240(or so) volts...Moral of the story overloads per motor work just fine to protect each motor and in turn the whole system...We have hundreds of machines with fan arrays run off one drive and never have issues...Danfoss has some energy optimization features that can be enabled for this purpose but they cause trouble with fans...
    "If history repeats itself I am so getting a dinosaur"

Page 2 of 2 FirstFirst 12

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Contracting Business
HPAC Engineering
EC&M
CONTRACTOR