Smart questions
Smart answers
Smart people
Join Eng-Tips Forums
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Member Login




Remember Me
Forgot Password?
Join Us!

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips now!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

Join Eng-Tips
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.
Jobs from Indeed

Link To This Forum!

Partner Button
Add Stickiness To Your Site By Linking To This Professionally Managed Technical Forum.
Just copy and paste the
code below into your site.

hhhansen (Electrical) (OP)
27 Feb 12 8:27
Hi out there
I am doing network studies on the LV distribution grid. According to prognosis we are facing a future with a huge amount of heat-pumps installed in the private house hold. I looked at a datasheet on a heat pump and it turned out that the starting current of the compressor is around 25 A. It is well known that induction motors inherently have starting current of 5 - 6 x nominal current.

My concern is about what happens when a large amount of heat-pumps are started-up simultaneously in terms of voltage drop, blown fuses in the 10 kV/0,4 kV distributions transformer LV switchboard. Can any of you share some experiences =? and/or are able to recommend litterature from studies, demonstration projects etc.

B.R. Hans-Henrik Hansen
Helpful Member!  waross (Electrical)
27 Feb 12 10:51
Many modern heat pumps have a built in random start delay of up to a few minutes. Simultaneous starting is not the issue that it once was.

Bill
--------------------
"Why not the best?"
Jimmy Carter

cranky108 (Electrical)
27 Feb 12 14:48
Besides that many thermastats also have a random restart/start feature.

A heat pump is not that much different than compressor air-conditioning used in many cities.

I would think the worst load impact would be all the backup heaters on in the really cold days.
davidbeach (Electrical)
27 Feb 12 15:33
Yeah, but the strip heaters respond quite graciously when presented with lower voltage due to overloading.  Completely unlike those greedy compressor motors that just stall on slightly lowered voltage and then pull down the voltage for everybody else.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close