On Thu, 2009-08-20 at 21:26 -0400, Gene Heskett wrote: > On Thursday 20 August 2009, Douglas Pollard wrote: > >My air compressor started up the same time I was starting my computer > >and crashed my hard drive. I have a small cheap compressor and its all > >the motor can do to start it and I guess it drew the current down. > >Anyway just something to think about!! > > Doug > > A good advertisement for installing a UPS. It doesn't have to be big enough > to run the mill although I did have one once that could. Basically, anything > that can supply the box for 3 to 5 seconds during such a brownout should at > least be a down payment on the insurance policy. > > However, I have not noted the lights dimming or flickering when my 2hp belt > driven 120 volt compressor fires up. I ran a hunk of 6-3 UF to the shop, > very little drop. But it took a slow, 20 amp breaker to have it stay up when > it starts, so it is a pretty decent pull.
Hi Doug I don't know where you live and my note is mostly a USA issue. Gene's post reminded me that the power company's neutral wire connection to your building might be at fault here. If there is any significant resistance between your neutral and the power company transformer, one side (120) of the 240 will dip badly while the other side jumps. I've seen this happen at quite a few locations around here. If you have a voltmeter, connect it to the same line side as your air compressor and start it. If the voltage drops under 100 then connect the voltmeter to an outlet on the other side of the line and start your compressor again. You should see a matching jump to 140 or perhaps more. The effect will be more pronounced if all of the 240 load, things like ranges and dryers are off. It's hell on light bulbs and such. Rayh ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
