Continual power supply

[bruce_taylor]

the power glitches are bothersome at best. Has anyone hooked up the shopbot to a ups system that would take it for short periods of power outages even 60 second so you could stop 000 out shutdown to start again without loosing everything. Wondering how much of s system would be needed? Anybody hace any thoughts?? Mostly wondering about the 5 hp colombo spindle??

[aaasigncom]

YES, ONE ON THE ROUTER TOO. AAASIGN.COM INDY

[dana_swift]

Bruce such systems are on the market, be prepared for something beyond "sticker shock", more like "sticker coma". The requirement for a UPS to keep a bot running is determined by the PEAK power used by the bot, so figure you need around 30A at 240V.

So the resistive power requirement for the UPS is:

240*30 = 7200 watts (VA)

Now we are running motors which are very reactive.. so double the power requirement to handle the reactive (power factor) component:

7200 * 2 -> 15000 watts (VA).

10000 watts (VA) may be enough, but that gets into the general area of the amount of power our bots pull when cutting at full depth. That should cover the spindle/router, gantry, and PC perhaps one or two "emergency" lights for the shop.

Your actual power requirement can be measured by observing your power meter. Your "mileage" may vary. That does not include dust collection, air compressors, etc.

So the UPS needs to be able to deliver around 10kva. (Less with a router, more with a spindle)

I did a quick lookup on the web for such a unit, my quick search found on the first link:

http://www.apc.com/resource/include/techspec_index.cfm

(I know nothing about this company or the quality of their products.. do a search of your own, I don't know how typical this is of the current market either.)

Note the price is just under $6000, and will supply power at full load for just under 5 minutes. (Also remember the batteries will have to be replaced every 3-4 years or so)

This unit outputs 208 volts not 240, so there may be issues there. No specification is provided for load imbalances with a split 120v configuration.

So the next question is: how much damaged material (scrap) are you creating per year due to power problems? Also how much opportunity cost is there in missed deadlines? If it justifies the expense, there are clearly devices on the market that can do the job.

Hope that gives you a direction to start looking for your answer.

Other factors to consider: do you need three phase power for a spindle? (A PC router requires much less power, so the system may be able to be much smaller if you use a router.)

If you do purchase a large UPS for your bot, I am sure the forum will be interested in your actual results.

Good luck-

D

[ron brown]

Bruce,

All it will take is money.

A 4kW continuous draw inverter should power a 5HP motor, not including startup surge. Perhaps a pair of Outback Brand grid interactive inverters and a good sized bank of batteries will do the job.

The inverters will be ~$2000 each, you will probably need 2 to get 240V for the spindle, a controller to properly link them and a bank of batteries of suitable size. I'd think $6000 or so if you installed it yourself.

Ron

Edit: written while dana was posting so I can add-

Get a real meter and find the true draw of the devices. I don't think the surge will be bad except for spindle startup and with a VFD, that should be controllable. The size of battery bank will determine the length of backup time.

Be aware a UPS "Interruptible Power Supply" may be meant for short term operation and the inverter/battery bank will stand constant use. All of the inverters I know that are heavily loaded need additional cooling for constant use.

[bruce_taylor]

time time time is the commodity that i'd like to save the files are 8 to 10 hours each and a glitch can be very difficult to recover from.
Material is only about $60/$80 per sheet. Piece of mind/priceless.
$6000.00 a little steep but not that shocking. Thinking about a set of battery banks and maybe a solar cell into the inverter and having
some green energy.Any thought on a way to stop the cut file in an outage and turn of the spindle automatically . Startup shouldn't be a huge issue i want to stopdown really the information is helpful and i'm going to look into this more.We get a lot of power glitches in the shop and most only a few seconds but very much a *^%#$%%%$$$ .

[garyb]

Bruce, I was going through a similar thing sometime back. Flicker in the power would knock down the computers in the middle of cut.
I called the power company who came out and tested everything, long and short of it we had low voltage & they were overloaded with customers on our line, they shifted the load around and cranked up the juice and that resolved the problem.

I would suggest you get in touch with your power supply company before dropping a bundle on back ups.
If the problem of power supply interruption is on the outboard side of the meter then the onus is with your power company, I found mine was very easy to deal with and resolved the problem with no qualms.
(even sold a 3d carving to the tech linesman they sent out)

[Gary Campbell]

Bruce...
Dont know what your machine config is, but if you run the new software, you can use a line voltage relay that is wired to a SB input configured as a STOP switch. When power goes off machine stops and spindle lifts...2-3 seconds. If you go in this direction, email.. I may have parts in stock to assemble one.
Gary

[donchandler]

On my old dos machine I have the computer hooked to a UPS and a line voltage relay hooked to the shopbot input that is the same as hitting the spacebar. If the power blips, the bot stops in it's tracks. The computer is still alive and still in the program. When the power comes back on, the router will start running and I just tell the program to resume. Starts right from where it was when the power dropped out.

[bruce_taylor]

great info, the reason alot of the time is storms in the afternoon.
I have talked to the power company and upgraded the service but it is still an occasional thing. I'm using an older version of sb3 that I'm comfortable with but was going to update to run ecabs once Guru Gary Campbell has the bugs worked out.I have a prt alpha 2005/2006 vintage. Great machine, works so well I'm a little apprehensive to change to much.If I could get to where Don Chandler is or Gary above I would be really happy. Interested in the 7.2 upgrade and maybe I could combine the two. Didn't have the funds when it was a deal with the trade-in now about $1500 ?? Have to give shopbot a call to check that out
but now I'm in a better place but need to keep my bot alive to stay their.Everyones help is very much appreciated.

[Gary Campbell]

Don...
Some of the later versions of the software allow you to configure any one of your inputs as a stop, limit or standard switch in either NO or NC. The older versions did not allow setting them as a stop switch. This configuration gives the bit lift, spindle off action that you are looking for.

You can activate the input with a relay or optoisolator, or both and a chunk of line cord. I like adding the optoisolator to keep the line voltage as far away from my inputs as possible.
Gary

[zeykr]

Gary,

Can you come up with a list of suggested part numbers. I'd like to set up a stop when there is a power flicker. Of course problem here usually has seemed to be losing one leg of 3 phase so simply hooking into 120 outlet may not catch it.

Thanks
Ken

[Gary Campbell]

Ken...
Depending on the actual voltage of each of the 3 phase legs to ground, I would use the OPTO 22 brand G4IAC5 or G4IAC5A on each leg. The outputs would need to be in series and connect from -5VDC to the input. Input would be configured as a NC STOP switch.

The same could be done with relays of the appropriate coil voltage. With the relays you could select the NO or NC contact set and then use them in series as a NC switch, or in parallel as a NO switch. Results are the same.

I looked & I dont have any line voltage AC coil relays, so no part numbers for them, there are hundreds of places to order them online.
Hope this helps, Gary

[zeykr]

Thanks Gary,

I've used several opto 22 devices in the past and will look those up.

Ken