Haven't been around in a while, thought I'd stop back and see if you iron heads had an opinion on this.
I've got an 80 gallon tank, a 5hp 3ph motor, and a newly rebuilt Ingersoll Rand t30-253 compressor pump.
Because the little box that sets your limits only allows me to set the top range and the differential, I have it set to 125 lbs psi, and the differential to its lowest point - 35 lbs, which means the compressor kicks on at 90 lbs psi. I'd prefer a smaller range, but that's what I've got to work with for now.
Since I just rebuilt the pump, I'm paying closer attention, and I've realized that with ONE standard dynabrade sander running nonstop, the compressor is running an average of 7.5 minutes between cycling again, and then running an average of 3.5 - 4 minutes each time.
To spare you all the math, that means that for every hour of use by one sander, the compressor is running for a half hour, and I'm paying for the electricity to turn over a 220v 5hp motor 8 times!
Does this seem as insane to you as it does to me? I'm not even sure where to begin troubleshooting this. Anybody have any ideas?
Compressor cycle frequency
Moderator: crzypete
Yo Buck,
Air tools are definitely not the most efficient things to use. But they are popular in in industrial settings where their motors last longer and are smaller.
I am guessing by the 125psi that your compressor is a one-stage?
Your math is slightly flawed. The compressor would have to on and off for equal amounts of time to run for 1/2 and hour during that hour of sander use. You are closer to 20 minutes per hour. Hope that makes you feel better.
Hopefully someone with more knowledge will chime in, I don't run air sanders.
Pete
Air tools are definitely not the most efficient things to use. But they are popular in in industrial settings where their motors last longer and are smaller.
I am guessing by the 125psi that your compressor is a one-stage?
Your math is slightly flawed. The compressor would have to on and off for equal amounts of time to run for 1/2 and hour during that hour of sander use. You are closer to 20 minutes per hour. Hope that makes you feel better.
Hopefully someone with more knowledge will chime in, I don't run air sanders.
Pete
Wait - giving it too much air would make it MORE hungry for air? Now I'm really confused.nektai wrote:The only though I have is surely not the solution but i will ask it for my own knowledge base. Is it possible that the sander is designed to be regulated below 125psi? This could account for its insatiable hunger for air.
And Pete - no, it's a two stage pump.
And here's my math - 60 minutes divided by 7.5 minutes per cycle is 8 times the machine kicks on each hour. Staying on an average of 3.75 minutes each time, 8 X 3.75 = 30 minutes.
But I draw full scale to avoid math, so I'm sure I'm doing something wrong there.
I feel like I'd like to set the top psi to something lower than 125, but since 35 lbs is the smallest differential I seem to be able to set, I really can't. Should I be looking for a new regulator? Maybe something that allows me to set a top and bottom, rather than a top and only a differential?
I'm definitely stabbing in the dark on this one. When it comes to this kind of shit, I'm dynamite with a spokeshave.
- Scott
I think that you may need an additional regulator.
Two stage compressors are capable of more than 125 psi (top end for an average single stage compressor) I would think in the 150- 175 range but a bit of research will clarify that point. Then i would add a regulator before the run of tube that distributes air through your shop. I would regulate the pressure to the top amount you need for any of the tools that you regularly use. I would also want to be aware of the pressure that each tool requires and individual regulators may be necessary.
In my shop it goes like this
Single stage compressor that maxes out at 125 psi.
I use that pressure throughout the copper network. This is perfect for all of my nail guns, blowing work off and the like.
I regulate down the pressure at my HVLP gun, for the air clamps on the multi router and at my timesaver.
Finally it is possible that feeding your sander more air than required is wasting air as it is emptying your compressor at too fast a rate.
Two stage compressors are capable of more than 125 psi (top end for an average single stage compressor) I would think in the 150- 175 range but a bit of research will clarify that point. Then i would add a regulator before the run of tube that distributes air through your shop. I would regulate the pressure to the top amount you need for any of the tools that you regularly use. I would also want to be aware of the pressure that each tool requires and individual regulators may be necessary.
In my shop it goes like this
Single stage compressor that maxes out at 125 psi.
I use that pressure throughout the copper network. This is perfect for all of my nail guns, blowing work off and the like.
I regulate down the pressure at my HVLP gun, for the air clamps on the multi router and at my timesaver.
Finally it is possible that feeding your sander more air than required is wasting air as it is emptying your compressor at too fast a rate.
buck shot wrote:I thought you were saying it would run for 3.5 minutes then be off for 7.5 minutes- so about 11 minutes total- thus my math of about 6 cycles per hour........nektai wrote: And here's my math - 60 minutes divided by 7.5 minutes per cycle is 8 times the machine kicks on each hour. Staying on an average of 3.75 minutes each time, 8 X 3.75 = 30 minutes.
- Scott
wondering aloud, I am curious what the most efficient range for that pump is. Perhaps letting it run closer to its 175 psi limit and as Nektai says regulate down from there.
To reaffirm what Nektai said, you need to figure out how much air the sander requires and regulate to that- thus you use air slower.
Pete
buckshot and gang,
as it has been said air powered sanders use crazy amounts of air, adding regulators etc. will only allow you to regulate but will not change the volume of air needed to run sander and right back to your concern of cycle time.
my concern long ago with frequent cycle time and or constant running time due to air powered sanders was moisture in airlines ultimately ending up in unwanted places, finish room, timesaver, edgebander etc. so i invested in a air drying rig by dayton with much success. also i installed drops in air lines with drain taps to combat moisture.
switching to electric sanders will greatly reduce compressor cycle time, i am looking at the new festool rigs, $$ but quality stuff
dadude
as it has been said air powered sanders use crazy amounts of air, adding regulators etc. will only allow you to regulate but will not change the volume of air needed to run sander and right back to your concern of cycle time.
my concern long ago with frequent cycle time and or constant running time due to air powered sanders was moisture in airlines ultimately ending up in unwanted places, finish room, timesaver, edgebander etc. so i invested in a air drying rig by dayton with much success. also i installed drops in air lines with drain taps to combat moisture.
switching to electric sanders will greatly reduce compressor cycle time, i am looking at the new festool rigs, $$ but quality stuff
dadude