The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

   
Topic Options
Rate This Topic
#59329 - 12/01/05 07:08 PM Surge suppressor and loose neutral
Edward Offline
Member
Registered: 12/14/02
Posts: 309
Loc: California
Will a surge suppressor protect computers against a loose neutral on a three wire system ?

my guess is it will not. But i like to hear you as well.

Thanks
Edward
_________________________
Thanks
Edward
Top
Work Gear for Electricians and the Trades
#59330 - 12/01/05 07:24 PM Re: Surge suppressor and loose neutral
yaktx Offline
Member
Registered: 02/19/03
Posts: 286
Loc: Austin, Texas, USA
I don't think so. I wouldn't bet my computer on it, anyway.
Top
#59331 - 12/01/05 08:15 PM Re: Surge suppressor and loose neutral
JoeTestingEngr Offline
Member
Registered: 11/04/05
Posts: 786
Loc: Chicago, Il.
It would probably offer you some protection but it wouldn't be doing quite what it was designed to do. If the leg you were on made excursions close to 240VAC because of a heavily loaded opposite leg, the MOV H-N in the suppressor might start clamping the sine wave. The MOVs would be dissipating energy for repetitve mS instead of infrequent uS or nS, as they are designed for. It would be a race between the MOV to blow or the overcurrent protection to trip. If the the MOVs clamp higher than 240VRMS, the suppressor would be of no use.
Joe
Top
#59332 - 12/02/05 12:22 AM Re: Surge suppressor and loose neutral
e57 Offline
Member
Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
I can tell you.... NO PROTECTION WHAT SO EVER!

Surge strip fine, computer power supply TOAST!

See this thread.... http://electrical-contractor.net/ubb/Forum1/HTML/006595.html
_________________________
Mark Heller
"Well - I oughta....." -Jackie Gleason
Top
#59333 - 12/02/05 05:44 AM Re: Surge suppressor and loose neutral
gideonr Offline
Member
Registered: 12/18/04
Posts: 152
Loc: Edinburgh, Scotland, UK
If your computer power supply is a wide range input type, typically 90 to 240 volts, then it should survive. Most recent ones here in europe are this type, especially as they now must have power factor correction built in.
Top
#59334 - 12/02/05 07:43 AM Re: Surge suppressor and loose neutral
renosteinke Offline
Cat Servant
Member
Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
Funny, my experience says "yes." I once made a poor neutral connection, and during the night fried a stereo power supply, a couple ballasts, two UPS units, and several surge suppressors; the computers that had the power strips before the UPS (or computer) came through undamaged.
Top
#59335 - 12/02/05 03:54 PM Re: Surge suppressor and loose neutral
JoeTestingEngr Offline
Member
Registered: 11/04/05
Posts: 786
Loc: Chicago, Il.
e57: I can tell you.... NO PROTECTION WHAT SO EVER!

renosteinke: Funny, my experience says "yes."

Well, I can certainly see how you both could be right, depending on the selection of MOVs or TVSs(Transorbs) inside your surge suppressors.

Joe
Top
#59336 - 12/02/05 08:19 PM Re: Surge suppressor and loose neutral
sierra electrician Offline
Member
Registered: 02/12/05
Posts: 220
Loc: North Fork, CA USA
I once broke the nuetral feeding a strip type surge suppressor...POW!!! It sounded like someone fired a pistol. The suppressor blew up, but the computer that was plugged into it was fine. Go figure.

Rob
Top
#59337 - 12/03/05 10:15 AM Re: Surge suppressor and loose neutral
gfretwell Offline


Member
Registered: 07/20/04
Posts: 9066
Loc: Estero,Fl,usa
Many years ago one of the computer trade rags did a story on this. Thier conclusion was a good strip would protect you if the on strip O/C device opened up with the MOV overload.
A lot still depends on the threshold and current capability of the MOV.
_________________________
Greg Fretwell
Top

Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box

Recent Posts
Forum Styles
by Admin
Today at 02:08 AM
License exam
by TRUE POWER
Yesterday at 09:16 PM
Looking for older post
by sparkyinak
Yesterday at 12:27 AM
Members: Non-Members: Did you know?
by Admin
01/22/17 02:34 PM
Safety at heights?
by HotLine1
01/21/17 08:51 PM

Who's Online
0 registered (), 84 Guests and 15 Spiders online.
Key: Admin, Global Mod, Mod
New in the Gallery:
Desk-mounted "power-board"
Top Posters
gfretwell 9066
Trumpy 8560
pauluk 7693
HotLine1 6833
sparky 5545
Member Spotlight
Member Since: 11/11/05
Posts: 190

ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals