ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Childrens safety outlets
by dsk - 06/25/22 04:07 PM
AC-DC stage Ultra-Fast charger, how it's made?
by libellis - 06/25/22 12:17 PM
Your favourite food?
by NORCAL - 06/16/22 12:06 AM
Price action trading with RENKO
by gfretwell - 06/15/22 02:08 PM
Please Help Wiring DCDC Buck Converter
by gfretwell - 06/15/22 01:58 PM
New in the Gallery:
240/208 to a house
240/208 to a house
by wa2ise, October 9
Now you know.
Now you know.
by Tom_Horne, September 7
Who's Online Now
0 members (), 30 guests, and 11 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: Sep 2014
Posts: 2
New Member
We installed 5 new Daikin A/C units on a large house with a back up generator and there are problems with the low voltage at generator start up messing with the A/C units (blowing fuses, etc.) Any recommendations on how to delay the power up of A/C units to after the generator stabilizes such as a time delay power relay that we could install that is available? Thanks


Chris Crawford, Space Options, Molokai Hawaii
Joined: Nov 2005
Posts: 826
J
Member
I would think it best to make sure any ATS doesn't switch until the emergency source is within frequency and voltage tolerances. Then, if I had problems with multiple compressors trying to start at the same time, I would consider TDOs on the control voltages. By time delay switching power to the control ckts, the units would just "wake up" at different times after a power outage. All high currents would be switched as they always are. This would also help on return to the normal source, and if set long enough, help prevent short cycling of the compressor(s).
Joe

Joined: Jul 2004
Posts: 9,696
Likes: 11
G
Member
Most HVACs have a time delay module in them from the factory these days but they are a delay after power off deal. If the power was off for X minutes it starts immediately.
For the OP's problem you want "delay on" relays set to different times for each compressor.
Five to Ten seconds between starts should do the trick without being that noticeable to the users.

http://www.grainger.com/category/time-delay-relays/relays/electrical/ecatalog/N-8erZ1z0move


Greg Fretwell

Link Copied to Clipboard
Featured:

Tools for Electricians
Tools for Electricians
 

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
Samurai
Samurai
Fl.
Posts: 46
Joined: May 2007
Top Posters(30 Days)
triple 3
dsk 2
dobler 2
Popular Topics(Views)
293,045 Are you busy
225,027 Re: Forum
210,453 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5