What's new
What's new

Machines - Leave em on or shutdown overnight

ducesrwld

Cast Iron
Joined
Mar 27, 2008
Location
S.E. WI
Curious what most small shop guys think on the subject. We only run 1 shift and are starting to run some 2nd shift on a few machines so they may run 12-16 hrs a day. At what point if any do you guys leave your machines on overnight if they aren't running lights out? I've always been under the mentality of letting the old girls cool off til morning. In the morning come in grab some coffee and fire machines up and run a warm up routine. None of my machines are anywhere near new all are 20+ years old.

Just had a buddy in granted he works in a production environment running 3 shifts around the clock and he said leave them on. I get it if the machines rarely catch a break but does that still hold for the job shop environment.

Just trying to see the pros and cons on both fronts. Most smaller shops I've been in everything gets shut down for the night....
 
The small shops I was at we just left em on, shut the lights off and leave. Mainly from the "what if my back up battery dies" mentality.

Yer gonna get a bunch of responses going either way...FYI:)
 
IMHO...

Power failures, lightening strike, power usage- we turn them off if they're not producing. Batteries are cheap they get changed every 2 years.
 
Even if left turned on sitting all night they will not be "warmed up" so that benefit is nonexistent.
If I let a grinder sit for a one hour lunch it is not warm and changes. It will need three or four empty or run cycles to get back to being happy.

Some machines are a pain to rezero so some savings here.
There may also be something to not cycling power supplies and other electronics and life span.

In a one shift shop it eats power all night at some cost but you save the time to power it back up and home. The wage per time spent is what?
Also note that by definition the new home/zero is likely +/- one count from the last.

In my thinking this is a very good question for a one shift shop.
Bob
 
Turn it off if it's not running. The electronics will live longer, and you'll burn less power. Spindle warmup cycle every morning unless it was still running when I came back in.
 
Turn it off if it's not running. The electronics will live longer, .

will they? Not being rhetorical, I don't know the the answer, but I recall something about the power on cycle puts the most stress on electronic components. Curious if any of you has the definitive answer.
 
Those vertical axes consume a fair amount of power just sitting there... Just sayin'. E-stop will at least turn the drives & brakes off, and conserve a little energy that way.

I hadn't thought about lighting or power disruptions though. Good point there.
 
I have a machine that if I power it down completely it will take about 30minutes to one hour to power back on without a fault. So sometimes it stays on but typically I shut it down because it doesn’t run that often
 
Not liking the thought of power outages and spikes, so full power off. Did have a machine that had an issue that hated startup so we left that on for months [emo'd] until I got to fix it
 
I power mine off. If I were to leave it on I would at least power off the drives, and lube pump. I don't want my machine sitting there trying to hold position for no reason. As for lightning strike safety if you don't physically unplug it so the high voltage spike has at least several inches, or feet, to jump then you have no safety. A gravel pit near where I worked had a lightning bolt strike their transformer one night, fried every single electric motor they had and everything was shut down. Lightning is scary!
 
Shut em down. We have a 5.5hr gap from when the last guy leaves and I come in. I just show up 20-30 min early everyday and run the warm up routine so their ready by the time the morning crew get in. Plenty of time to make some coffee and have some breakfast.
 
will they? Not being rhetorical, I don't know the the answer, but I recall something about the power on cycle puts the most stress on electronic components. Curious if any of you has the definitive answer.

Every individual machine or device will have a different ratio, but I read about my LED lights that something like three hours of operation is equivalent in wear to turning them off and on again once. So I wouldn't turn it off in the middle of a workday if it's going to sit for a bit, but I would turn it off overnight.

Old, unreliable, or poorly designed machines may be a different story.
 
Shop I used to subcontract my products to before I got my own machines always left them on, they thought it did them more harm turning them on and off every day, that may have made some sense when they ran a two shift day but when they dropped to single shift I'm not so sure.

I run low volume production so I'm not the average guy but even when I'm doing days in a row on the same machine I turn them off and unplug them at the end of the day (every machine has plug and cable to allow me to move them around without a sparky), they get a short warm up cycle as a minimum every day anyway, I know on one of my lathes the autolube runs even when the drives are all off so it seems like a waste of energy to leave them on. I normally have a quick tidy while they're powering up and the warmup cycle is running so I don't see it as wasted time.

Same goes for my compressors, valves off, switches off, unplugged unless I'm there using them.
 
I think it all comes down to who pays the bills lol.

We have like 50 or 60 vacuum melt casting cells...that work 24/7...I doubt the electricity to run our wire and haas overnight comes anywhere near one of those in year lol.

Funny observation, we are fed from 2 sub stations and the wires coming into the buildings are huge...main transmission line huge lol.

Interesting fact, for electricity and water we are considered a top priority customer. Like drop everything and fix it now priority.
 
When I worked for a digital readout manufacturer, they recommended leaving the DRO display on 24/7. The heat / cool of turning it on and off caused more failure than leaving them on. But this was just for the DRO display. Don't know how that would compare with a CNC control.
 
Some stuff takes longer to start up.
Not a cnc but If I shut down one of my carb furnaces it would take 3 days to reach dew point again so we just pushed empties.
How about office computers or other PC type stuff. Longer life if left on and let them go into power saving mode or even turn this feature off?
My experience here is do not turn off.
On a cnc how about an e-stop that kills the drives but leaves the cpu/plc side running?
 
Yer gonna get a bunch of responses going either way...FYI:)

Yup...that's the whole point. I was really scratching my head when we briefly talked about the subject I had never thought about leaving the machines on and had just always had it in my head when the day is done the machines get shut off.

But...I'm a dip when it comes to the electronics side of things. Not sure if its better to be powered up or down if there is a lightening strike, ect....My lathes were powered down but a building strike didn't stop a lightening strike taking out 2 boards and mucking up 2 machines.

The engineer in me I don't sleep as well leaving machines on while they sit idle doesn't make any sense to me to leave them on but I figured this would be a good topic cause if someone asked me why....the answer is because that's what we've always done.

I do have an old '80s Matsuura we are reviving from the dead and it has been a major pain in my ass. We decided to leave the machine on as I was getting a lot of alarms trying to get it rolling each morning. Worked great the first day after day #2 end of 2nd shift spindle drive throws a code and I can't clear it...lost a few hours of production that night. some things are just darned if you do darned if you don't.

I'm sure there are reasons on both sides for what I thought was a dead simple answer of shutting machines down but doesn't hurt to take the blinders off once in awhile and listen...
 








 
Back
Top