Haven't posted anything on here for quite a while, but do enjoy getting on and reading posts on tools from other. Now, I'm in need of a little help with an air compressor I've had in my shop for 3 or 4 years now and never hooked it up. My main one is an 80 gallon Devilbiss 432, which will stay where it is in the basement but now I want to go ahead and move this other one up to the upper garage, near my lift. Now that I have the interest to move it and get it going again, I've been searching for a few days, apparently in vain, for some information on it. It is a Wayne/LeRoi, vertical tank (believe it's 80 gallon) twin cylinder, 2 stage with a brand new 5 HP Baldor 1725 RPM motor. The model number tag on the pump says TRU 5 N and the tag itself it from LeRoi. The tank was built in 1993 and has a large Wayne decal on it. I really don't think this thing has been used too much, wherever it has been, prior to me buying it. It is a little dirty/dusty from being in my basement shop but other than that, it's near perfect. It is also INCREDIBLY heavy duty - and incredibly heavy altogether! The steel plate that forms the base for the pump and motor is 1/4" thick. The Devilbiss is a monster, with the pump alone weighing in at 271 lbs. and the motor at 100 lbs., and the plate on it is 3/16". Don't think I've ever seen any kind as heavily built as this Wayne. I haven't been able to find ANYthing in regard to the pump. I know Wayne is no longer in business and was bought out by LeRoi but I can find nothing on either. I calculated the pump RPM at 948.75 with the motor having an 8.25" pulley and the pump flywheel/pulley being 15" - they are double sheave too. What I'm concerned with is the pump RPM. The guy I bought it from (For $250.!) just put the new motor on it but it kept tripping the breaker in his home garage, so he just bought something much smaller. Although I haven't had the chance yet to look at how he had it wired, I'm thinking he has something crossed up or maybe it was something really simple, like he didn't have a large enough capacity breaker. This is a REAL 5 HP motor and pulls quite a few amps. Anyway, I'm not sure if the pulley he has on this new motor was the one the compressor had originally, so I'd really like to know the optimum operating RPM for this pump to make sure. If anybody out there has any information about this, or knows where I can access some, please let me know - it would be much appreciated! I've attached a few pictures for reference...hope they come across OK...Thanks in advance for any help!! I'd like to get this one running properly pretty soon...
Wayne/LeRoi compressor TRU 5 N
- Thread starter drsamm
- Start date
bczygan
Well-known member
Can't you find the needed info from the prior owner? Does he have the original motor? Did he change the pulley and does he have the old one?
Bill
Bill
matt_i
Well-known member
Three easy checks are to roll over the compressor by hand and make sure that its relatively smooth. Its not driving a camshaft and so it won't be as lumpy as an IC engine. But should be free and you should sense the compression building.
Wire up the motor to 240vac and run the motor by itself (no belt)
Verify oil level in the compressor.
After those all check I would put the belts back on and let it eat.
30A breaker & #10 awg THHN is probably sufficient but you could go to #8 & 40A if its a long run.
Wire up the motor to 240vac and run the motor by itself (no belt)
Verify oil level in the compressor.
After those all check I would put the belts back on and let it eat.
30A breaker & #10 awg THHN is probably sufficient but you could go to #8 & 40A if its a long run.
MacMcMacmac
Well-known member
This is a Schultz MSV-30 pump made in Brazil.
metlmunchr
Well-known member
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LeRoi was sold to Westinghouse Air Brake in 54.
Dresser acquired LeRoi in 72
From 91 to 96 LeRoi was privately owned.
From 96 to 05 it was owned by Comp Air Group
From 05 to 2017 it was owned by Rotary Compression Technologies
In 2017 it was acquired by Gardner Denver.
In 2017 Gardner Denver also merged with and became part of Ingersoll Rand.
This sort of ownership chain usually guarantees a shortage of information on legacy products.
The 5 in the model number would indicate that it is intended to be driven by a 5hp motor based on the fact that a 7.5 hp version is currently for sale online, and the pump is listed as a TRU 7.5 N.
My guess is that yours is set up now to run too fast. These comparatively massive pumps are generally older designs with large bores, and were designed to run at lower speeds. Newer designs have smaller pistons and are designed to run faster for the simple reason that smaller is cheaper to build.
Among my collection of compressors, I've got two 10hp units with V type compressors. One is a Meiji which is a Japanese design from the 80's. The first stage cylinder bore on the 5hp version is about 3.6" and the design speed is 940 rpm.
The other is a Westinghouse Air Brake which is an early 60's design from the time when they also owned LeRoi. First stage bore on that 5hp version is 4.5" and the design speed is 820 rpm. The Westinghouse pump bears a strong resemblance to your pump but they are not identical.
As said previously, all the above is just a halfway educated guess as to the correct speed for your pump. The real proof would be to wire it and belt it as is and then check the load with an amprobe. IIRC, the circuit sizing for a 5hp single phase motor will be a 40 amp circuit. AFAIK, all 2 pole breakers are now the hacr type which have sufficient trip delay to allow for motor start current. If a 40 won't hold it at startup you can safely assume the drive pulley is too big. If it starts okay, then it's just a matter of monitoring the current as the pressure builds to determine if its staying within the nameplate amps.
Dresser acquired LeRoi in 72
From 91 to 96 LeRoi was privately owned.
From 96 to 05 it was owned by Comp Air Group
From 05 to 2017 it was owned by Rotary Compression Technologies
In 2017 it was acquired by Gardner Denver.
In 2017 Gardner Denver also merged with and became part of Ingersoll Rand.
This sort of ownership chain usually guarantees a shortage of information on legacy products.
The 5 in the model number would indicate that it is intended to be driven by a 5hp motor based on the fact that a 7.5 hp version is currently for sale online, and the pump is listed as a TRU 7.5 N.
My guess is that yours is set up now to run too fast. These comparatively massive pumps are generally older designs with large bores, and were designed to run at lower speeds. Newer designs have smaller pistons and are designed to run faster for the simple reason that smaller is cheaper to build.
Among my collection of compressors, I've got two 10hp units with V type compressors. One is a Meiji which is a Japanese design from the 80's. The first stage cylinder bore on the 5hp version is about 3.6" and the design speed is 940 rpm.
The other is a Westinghouse Air Brake which is an early 60's design from the time when they also owned LeRoi. First stage bore on that 5hp version is 4.5" and the design speed is 820 rpm. The Westinghouse pump bears a strong resemblance to your pump but they are not identical.
As said previously, all the above is just a halfway educated guess as to the correct speed for your pump. The real proof would be to wire it and belt it as is and then check the load with an amprobe. IIRC, the circuit sizing for a 5hp single phase motor will be a 40 amp circuit. AFAIK, all 2 pole breakers are now the hacr type which have sufficient trip delay to allow for motor start current. If a 40 won't hold it at startup you can safely assume the drive pulley is too big. If it starts okay, then it's just a matter of monitoring the current as the pressure builds to determine if its staying within the nameplate amps.
Thanks to all for the input... I don't have access to the previous owner, so can't get any questions answered from him. I did turn the flywheel on the pump to make sure of no funky sounds or binding, etc. and it spun as it should with no sign of any problems. I'm by no means an electrician, so the amperage draw might be a concern. The plan is to have it about 50' or so from the breaker box that will supply it, connected with 6 gauge Romex but it is a 30 amp breaker. As for the RPM, I too thought that 948 was a bit high. I would think in the mid 800's would be optimum, but that's why I was looking for some concrete specs. on it. Of course, too low with the RPM's will not allow it to lubricate itself properly. The Schultz picture does look very much like it. I don't know much about Schultz compressors but I wonder if that one is a copy of the LeRoi design? Anyway, I think I'll size the motor pulley differently to see what will give me around 850 RPM or so. Absent of any sort of printed material of the specs. for this particular pump, I would think that is about right..
I looked up the technical specs on the Schultz compressor pump that MacMcMacmac posted above, thinking that since it's so similar (in appearance only, since I have no idea what the bore and stroke is on mine) it could give a clue about optimum RPM on the LeRoi. According to their specs, it spins at 1050 RPM with a 5 HP motor. The flywheel on that pump is 16.5", so assuming a motor speed of 1725 RPM, it would take a 10" pulley for the motor to achieve that pump RPM. It just seems to me that this is too high for the LeRoi. Of course, the whole idea to a 2 stage pump and a 1725 RPM motor is for everything to spin slower, to not be so annoyingly loud and to last much longer as well as come up to pressure faster. Anyway, with a 7.35" OD pulley on my 1725 RPM motor, the pump will spin at 845 RPM - a 7.50" will yield 862 RPM, an 8.0" will yield 920 RPM and finally, an 8.25" will yield 949 RPM. I guess I'm over thinking this as it might not make too much difference one way or the other, as long as you aren't out of the park either up or down. I just want to insure that it has adequate oiling more than anything else. It won't be in constant use anyway, so at any RPM, as long as it oils itself correctly and all else works as it should, I'm relatively sure that it will long outlast me...Any other opinions for this?
MacMcMacmac
Well-known member
https://www.compressorpros.com/repl....5hp-two-stage-cast-iron-air-compressor-pump/
I'm not sure where you got your specs but the Schulz site says it needs 7.5hp to turn it 820rpm. Other sites list it as a 5hp pump, so it would seem Schulz is running smaller pumps at higher rpm to move them up a class, like IR did with all of their stuff. 820rpm isn't too bad though, so I would expect one of these running at less than that at 5hp to last a very long time. These pumps also had needle bearing small ends and a nice concentric disc valve arrangement like the old tough IR Type 30s used to run. These are quite nice machines.
I doubt this is any copy, Champion also used these pumps on their cheaper line of machines, and a company called Ranger built up their compressors with them as well. Top tier companies like LeRoi often put cheaper import pumps on a value line of machines to compete in the lower end of the market. It would be nigh on impossible for them to have sold any of their top of the line pressure lubed pumps at any price that would have made sense to move enough of them in the consumer market to have been worthwhile. This is the same reason Quincy sells QT series units. No one is going to pay $3000 for a bare pump, outside of industry, which fully expects their investment to last them a good 20 years or so under pitiless operating conditions.
You can check the dimensions of your pump against the diagram on that site and see if they match up.
I'm not sure where you got your specs but the Schulz site says it needs 7.5hp to turn it 820rpm. Other sites list it as a 5hp pump, so it would seem Schulz is running smaller pumps at higher rpm to move them up a class, like IR did with all of their stuff. 820rpm isn't too bad though, so I would expect one of these running at less than that at 5hp to last a very long time. These pumps also had needle bearing small ends and a nice concentric disc valve arrangement like the old tough IR Type 30s used to run. These are quite nice machines.
I doubt this is any copy, Champion also used these pumps on their cheaper line of machines, and a company called Ranger built up their compressors with them as well. Top tier companies like LeRoi often put cheaper import pumps on a value line of machines to compete in the lower end of the market. It would be nigh on impossible for them to have sold any of their top of the line pressure lubed pumps at any price that would have made sense to move enough of them in the consumer market to have been worthwhile. This is the same reason Quincy sells QT series units. No one is going to pay $3000 for a bare pump, outside of industry, which fully expects their investment to last them a good 20 years or so under pitiless operating conditions.
You can check the dimensions of your pump against the diagram on that site and see if they match up.
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I actually got the specs on the Schultz pump from their pumps catalog. It appears that the one like the picture you attached comes in 3 different forms - an MSV 20 MAX, a MSV 30 MAX and an MSV 40 MAX. the 20 is the one that takes the 5 HP motor, like the LeRoi I have, the 30 takes the 7.5 HP and the 40 takes a 10 HP. The catalog is at: https://www.compressorworld.com/amfile/file/download/file_id/7768/product_id/890/ The pumps I'm referring to are about 3 or 4 pages in. I wasn't thinking that the Leroi was any sort of a copy of anything, rather, I was thinking that possibly the Schultz was the copy of the design. I've always heard that LeRoi, DeVilbiss (Older ones) IR (mostly older ones) Champion, Saylor Beall and Quincy were all top shelf - again, maybe not so much the most current of any of them. Regardless of all of that and absent of any credible factory information, I would likely be better off to run this one at around 850 RPM. If I can't find some concrete information, I suppose I'll try it and see...
matt_i
Well-known member
I snipped this out just because I think a 30A is good enough, most 5hp are around 22 FLA and multiply by 125% of that to satisfy conductor sizing for NEC Article 430. So 22 x 1.25 = 27.5A. If your FLA = full load amperage from motor nameplate is different from that then it deserves another look at wire sizing.
Right or wrong, but based on those numbers, is how I wired the similar 5hp compressor in my shop.
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MacMcMacmac
Well-known member
You may be correct. I was basing my suggestion on the position of the HP discharge port and the fact that new MSV20s do not have a removable back cover.
It looks like newer versions of this pump no longer have the concentric disc valves either.
Edit: Yes, it looks exactly like this one
It looks like newer versions of this pump no longer have the concentric disc valves either.
Edit: Yes, it looks exactly like this one
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Well I'm looking to connect it with 6 gauge romex (which I have in hand) about 60 feet or so from the breaker box. I believe this will be more than sufficient for this motor and pump set up. I finally got the chance to look at the way he had it connected. He simply has an "ON"/"OFF switching box with screw in type fuses and the pressure switch. Again, I am no electrician, but I'm pretty sure a motor of this size should be wired into a magnetic starter. I'm thinking that the absence of one is why he kept blowing the fuses. When that thing starts, I imagine it takes quite a shot of power to get going. So now I'm looking about on Ebay and elsewhere for an adequate starter for this size motor. They don't appear to be too plentiful in single phase but I have found a couple that look good for it. By the way...for you electrical types out there...is there any reason that a 3 phase starter couldn't be wired up to work with single phase? I have a Furnas one from another large compressor that originally had a 3 phase motor on it. It is new as I don't think that compressor had ever been used, so I would hate to just put it on the shelf if it can be safely used. I had seen a youtube video from an electrical supply company that outlined how it could be done. Wasn't some guy in his back yard swapping wires in something to see what would happen - appeared to be 100% legit, but I'd like an opinion or two from some of the guys on here with hands on experience...any thoughts would be much appreciated...
MacMcMacmac
Well-known member
Yes, you can use a 3ph starter on single phase if you have the correct voltage coil on the contactor. If not, a control voltage transformer will be necessary. You will need a starter to use that low oil shutoff, since it will definitely not take full motor amps through it. It is only rated to break the circuit to the starter coil. The starter itself needs to be rated for the amp draw of the motor, and will need the proper sized heaters.