I am looking into converting a self serve bay into another automatic. I called the local power company (municipally owned) to let them know that I would need to increase my service to 400 amp capacity up from the current 200 amp. They said no problem, but we need to put a recorder on your existing wash to verify the need for a larger transformer. NOW, two weeks later, they are telling me that the inrush is too high and that they require soft starts on all motors over 15hp. Has anyone else dealt with this? I have installed equipment nationwide for 12 years and have never heard of this type of regulation before. How should I handle them?
25 hp motor soft start???
- Thread starter waright
- Start date
washnvac
Well-known member
A lot of electric utilites are requiring a soft start on 5 hp or more. It is no big deal. Just delete the starters from your equipment package, and get them yourself locally. I just did this on a new auto for my location. I installed 8 soft-starts--6 for the dryers, 1 for the 15 hp pressure pump, and 1 for the 15hp hydraulic pump. They will cost a bit more than the plain ole starters, but you will recoup the cost quickly on your electric. The demand charge on my bills was more than 50% of the bill. The soft starts will dramatically reduce the inrush. I have mine set to start up at no more than 250% than full load amps. Typically a motor start takes 500% of FLA. Total cost for my 8 starters was just under $5000. (two for 15 hp motors, and 6 for 7.5 hp motors.)
washnvac
Well-known member
WOW!! I did not think any power provider would give a commercial entity a flat rate because of the spikes. You are lucky in this case.
Greg Pack
Wash Weenie
Softstarts aren't that expensive, are they? About 1K per unit I thought? And we're talking two needed at this car wash. And supposedly there will be some electrical savings if peak metering is used? Personally, I wouldn't fret over it too much.....
Well, after typing this I see washnvac has essentiaslly said the same thing from the point of experience.
Well, after typing this I see washnvac has essentiaslly said the same thing from the point of experience.
GoBuckeyes
Self-Serve and Automatics
Washnvac, you may think that $5000 for 8 starters isn't much but I do. You could buy starters and protectors from AutomationDirect for those 8 motors for well under $800. How long will it take to re-coup $4200?
washnvac
Well-known member
Actually, I thought is was a $hitpot full of money at the time. My issue was adding a second iba to a 5/1 with 400 amp service. Everyone told me I needed 600 amp for a 4/2 plus 12 vacs plus vac-it-up system. Cost to upgrade--$35,000. Cost for soft starts for both autos- $10,000.
The direct savings to the electric demand portion for me was calculated out to $186 per month. So the payback on just the electric bill will be about 4.5 years; not including what I saved by not upgrading to 600 amp service.
So it was certainly the right thing for me. If demand or amperage draw is not the issue, then they are not a neccessity. I just feel all of us need to do our part to help offset the current energy demand. I incorporate solar/pv at three of my locations, as well.
what about installing capacitors on the motors. i was having a problem with our home air conditioners during start up, pulling such a load that our lights would dim momentarily. i installed what the HVAC people call jump start capacitors - which just install in series with the exisiting capacitor - and we have not had this problem since. i have not tested it but imagine that it has and is reducing my initial start up amp draw. is there any way to use these sort of devices with either the self serv equip or auto's.
MEP001
Well-known member
I don't believe you can just add a capacitor to a motor unless it's already a capacitor-start motor. 3-phase motors require a VFD programmed to spin up the motors rather than just slamming full voltage to them. There was a past thread on this subject some time back and someone mentioned adding capacitors, but when questioned about adding them to 3-phase motors they never responded to explain how or if it was truly possible. I'm fairly certain it isn't.
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ken-pro
Equipment Distributor
This thread: http://forum.autocareforum.net/showthread.php?t=3359 was the discussion of capacitors on 3 phase motors. They are available, and they do make some difference. My customer who has them claims his savings on hydro are somewhere around 15%. His calculated payback on a 4/1 site was about 3 years. I did not sell them to him, and I'm not sure about brand names or pricing.
