Question Bauer Capitano II 480V 3 Phase to 240V Single Phase Help

[happy-diver]

Yeah that's it 8kw, have to get a bigger one it's a bit slow starting my 5.5kw Bauer mini verticus

the electronics from their website

Should be respectable for the price but I'm the one that wanted 3phase

Cheers!

 

[BRT]

Mitsi is good stuff. The expanded instruction set was a real helpful tool for shortening up the amount of code you had to write. Things like Schmitt triggers were a canned routine.

The AB PLC 5 was another good system, once the newer programming software for it came out. Unfortunately, some components in that series got discontinued before they were scheduled to & some systems integration companies got hung out to dry when they couldn't make good on support contracts without replacing entire systems. I saw used parts from junkies like Radwell going for several times new price when the crunch first hit. A client in Detroit got hit pretty hard. The expensive programming cables with the little round connector were really fragile. I usually ended up making serial cables with handshake jumpers when I had to get inside one of those. The serial connection was slow, but reliable.

I haven't played with the PLCs from Automation Direct yet. Somebody told me they were made by Koyo or someone like that. I haven't played with the Westinghouse ones either. I know nothing about them.

We bought one Westinghouse, late 80's, to run a lumber sorter. They were kind of a big thing then but are dead so far as I know. The Automation Direct stuff is so cheap that it opens up possibilities. The PLC 5's were good, but not as reliable as the Mitsi's, and lots more money.

 

[Cio]

If varying speeds on compressors is always bad why do compressor manufacturers do it when they sell the same compressor with a smaller or bigger motor?

every reciprocating compressor will have an RPM (coupled with outlet pressure condition) In which the vibration induced by the rotating assembly matches the resonant frequency of the compressor assembly, this creates a vibration that "fuels" itself, increasing in magnitude and basically destroys the compressor head by shaking it to death. Because actual conditions won't let this occur in one shot it will sort of bounce in and out of an excited state in real worlds conditions.

When a manufacturer sells head and configures it at different speeds, those speeds are tested and proven to be safe. Testing is just about the only reasonable way to do this since a vibration analyses of something like this is just to difficult to do (to many conditions)

If a VFD is set up for closed loop control, these resonant frequency RPMs tend to be attractive to the control loop for one reason or another so closed loop control is a massive no no.

If you are just adjusting it with a knob, the unit will run steady state which is better and just leaves you relying on luck to avoid picking a bad RPM. As a generalization, luck is on your side, especially since you will hear something if the block is getting excited. If you use an RPM that the block is typically configured for, no worries, if you chose randomly, you are risking finding that bad combo.

There is a ton of literature on this, especially detailed when referring to rubber or spring couplings paired to IC engines. When IC engines get vibration dampening coupled to a reciprocating compressor, this is a major concern and through testing is required by the factory for these combos, electric motors belt driving a compressor are no where's near as problematic but it still exists, just solely in the compressor block. .

 

[Cio]

Compressors are using PLCs now?

As stated this is the norm for some time now, the machines I work with, email me and I can log into the HMI remotely and get them going in my PJs.

This one emailed me this week @ 4AM, got it going and went back to bed.

 

[Tracy]

I am really enjoying the direction this went off topic. I am learning all kinds of new things.

 

[Cio]

I really didn’t want to get into a protracted debate. I was trying to offer some oversimplified generalities to help the average Joe gain a basic understanding. But, I will reply to your assertions.

The compressor applications I spoke of were recips, not screws. It was my understanding that screws run into wear issues when they don’t run at their favorite speeds & that is why they are often undersized a little, then backed up by recips that can start & stop more frequently without doing damage. I know little about unloaders. But hey, I’m not a compressor specialist, so my knowledge base there is thin. I do know a few things about drives, motors & controls.

I did not understand that reciprocating saws & punch presses were different from the kind of reciprocating equipment that you were referencing. Thank you for the clarification.

I was not aware that it was a fact that reciprocating compressors are not meant to run at varying speeds. I’ve been running 3 phase compressors off of drives, that run off of single phase, in places that don’t have 3 phase available, for more than 20 years. Sometimes, I ran at speeds other than nameplate. I hadn’t noticed any issues, but perhaps issues were present & I just don’t know what to look for.

It would be my expectation that the increase or decrease in wear based on change in speed would be variable depending on the specific piece of equipment being examined. I also believe that if you change the basis of judgment, you will be able to change the outcome. Eg, wear per hour, vs wear per cf, vs wear per Kwh, etc. But that is just an expectation on my part. I don’t have empirical data to back it up. Perhaps you do.

Yes, reduced oil pressure could be an issue at reduced speeds. Most equipment with forced lubrication has a range of oil pressure with which it can run properly. Equipment that runs with regulated oil pressure tends to be particularly insensitive to reduced primary pressure. At some reduced RPM, this will likely become an issue. I expect that the minimum acceptable RPM for proper oil pressure would tend to vary with the specific piece of equipment, it's age & it's maintenance history. But hey, there I go stating a silly expectation again.

Reducing speed also reduces motor cooling, unless the motor has a separate blower (as many inverter rated motors do). That is also that detail, which I probably chose to overlook before.

As speed increases over nameplate RPM, a motor running off of a drive changes from constant torque range to constant HP range & the torque available from the motor DOES reduce as speed continues to increase, due to current limiting from the drive. That IS a fact of physics. That is how drives are designed to work. Ask anyone who designs drives for a living.

I did not realize that his motor was 480. Since 480v 1 phase is not commonly available where 480 3ph is not present, & motors of that type probably don’t exist, than you are correct. The change is not as simple as adding a jumper. You got me on that one. Good catch.

I have run into harmonic issues in some of the more complex projects that I have been brought in on. I have had more than one instance in which adding a new drive into a system caused another drive to trip out, or sustain damage. Sometimes those two drives were in the same machine. Sometimes they were in different parts of the same building. Sometimes they were in different buildings in the same complex. This has happened to me with high end Japanese drives and top quality German drives. I don't have experience with the stuff that gets sold on Alibaba.

I normally spec my motors at or just above calculated load capacity & oversize my drive a bit above the motor size. I then limit the beating that the motor takes by programming the drive correctly. Correctly programmed drives generally still beat on motors in 3 ways. 1) The spike voltages are higher than nameplate voltage, which requires improved winding insulation to avoid Corona effect. 2) The carrier frequency is higher than nameplate frequency & causes increased mechanical cycling on the windings & accelerates stress fatigue. 3) when running a motor with an armature fan at reduced RPMs, you have reduced cooling. Drive rated motors are designed to handle these additional challenges. Standard motors, take it on the chin a little.

I have never ever seen a VFD used along with a soft start. Please let me know what kind of application used that combination. I would love to learn something new today.

I have added a VFD to an existing motor hundreds of times. It almost always works out, unless the application was marginal to begin with or the motor was really old or the motor was really beat. When I say old, I mean more than 50 years.

I think you misunderstood me. I DISallowed claims on improperly wired drives. I’ll have to go back & see if I was the victim of auto spell correct or if you misread what I wrote.

Of the drives I have seen, most that fail in the first few months, fail from improper usage. Most that don’t fail in the first few months, but do fail in the first 5 years, fail from overheating due to clogged fans. Most that fail after 10 years, fail from bad capacitors. It could be DC buss caps or the bypass caps inside the thyristor packs on the output stages. Buss caps are sometimes changed as a maintenance item. The bypass caps are usually potted inside the TRMs & are not accessible. That covers about ¾ of the failures that I have seen. I see drives from a wide variety of different industries, but mostly automated manufacturing equipment, elevators, robotics & machine tools. Compressor specific failures may be different.

If you’re in NJ, I’m going to guess that you probably get your drive repairs done by that place in Parsippany. I think it was either on Edwards Rd. or New Rd, but I haven’t dealt with them in many years, so I forget. I do remember their repairs generally being a little slower than the ones I did, back when I did that sort of thing as a sideline.

I agree that it is hard to justify loosing the benefits of 3 phase & changing to single phase.
….unless you have equipment that is already 3 phase & you need to use it someplace that only has single phase power available. I think that is what is being discussed here.

I think that I have sold a grand total of maybe 3 soft starts in my entire life. I mostly use drives. I sometimes use servos (which are actually just drives with feedback). I occasionally use phase inverters. I still use traditional contactors, when appropriate, too. My asking you to check on the constant frequency statement regarding the soft starts is based on that claim conflicting with the claims of a factory rep from S&S who later became a factory rep for Rockwell. He claimed that his soft starts were variable frequency. He twisted my arm to sell a couple of them many years ago. I’m not up on what is currently available. If you are confident of that claim, I’m ready to call my question answered, & thank you for confirming that information.

Regards,
the fish

We are not talking about the same harmonics, I think you are talking about electrical harmonics, I am talking about mechanical, that's why we aren't understanding each other.

Running off nameplate isn't an automatic recipe for disaster, unless you use variable closed loop control, if you are running steady state, chances are you picked an RPM that fine. Its one of those things you just never know so nameplate or OEM configured RPMs are best to stick with.

I do not have any off RPM operation wear data, the equipment I work on is usually 100HP+ duplex stuff with tons of controls, no one would dare run these at other RPMs since they cost more than a house and failures on these are always thoroughly investigated. I can tell you that operators that start/ stop too often, do incur massive maintenance costs.

I think on the torque to RPM thing, you are referring to the drive which as you say, HP remains constant for that device as RPM increases over nameplate, that's how I understand them to work. I was referring to the compressor's demand, which will require constant torque and increasing HP as RPM increases. I think we are both correct, just not both referring to the same thing.

I've never used a soft start with a VFD, maybe I mistyped or you misunderstood, as you know, a VFD is a soft start.

Adding VFDs to existing Non VFD applications is a big no no as far as I know. I may be skewed in that I work on stuff that usually has high starting parasitic loads and when they vary, the loads require constant torque which, in my experience always calls for a sizeable upsizing on the motor. I guess I can see a lot of applications where this would be fine, it just isn't in my world.

I did misread your warrantee claim statement, failures I see are same as you, caps failing or dirt and dust. I have had some where transistors just fell out of them which was interesting (and easily repaired. )

I agree 3 PH is always better (and cheaper) 1PH is for when you have to.

The soft starts I have encountered were sold as a variable frequency, I cant truly argue this since I haven't had an oscilloscope on them but the idea makes sense.

 

[Cio]

I really didn’t want to get into a protracted debate. I was trying to offer some oversimplified generalities to help the average Joe gain a basic understanding. But, I will reply to your assertions.

The compressor applications I spoke of were recips, not screws. It was my understanding that screws run into wear issues when they don’t run at their favorite speeds & that is why they are often undersized a little, then backed up by recips that can start & stop more frequently without doing damage. I know little about unloaders. But hey, I’m not a compressor specialist, so my knowledge base there is thin. I do know a few things about drives, motors & controls.

I did not understand that reciprocating saws & punch presses were different from the kind of reciprocating equipment that you were referencing. Thank you for the clarification.

I was not aware that it was a fact that reciprocating compressors are not meant to run at varying speeds. I’ve been running 3 phase compressors off of drives, that run off of single phase, in places that don’t have 3 phase available, for more than 20 years. Sometimes, I ran at speeds other than nameplate. I hadn’t noticed any issues, but perhaps issues were present & I just don’t know what to look for.

It would be my expectation that the increase or decrease in wear based on change in speed would be variable depending on the specific piece of equipment being examined. I also believe that if you change the basis of judgment, you will be able to change the outcome. Eg, wear per hour, vs wear per cf, vs wear per Kwh, etc. But that is just an expectation on my part. I don’t have empirical data to back it up. Perhaps you do.

Yes, reduced oil pressure could be an issue at reduced speeds. Most equipment with forced lubrication has a range of oil pressure with which it can run properly. Equipment that runs with regulated oil pressure tends to be particularly insensitive to reduced primary pressure. At some reduced RPM, this will likely become an issue. I expect that the minimum acceptable RPM for proper oil pressure would tend to vary with the specific piece of equipment, it's age & it's maintenance history. But hey, there I go stating a silly expectation again.

Reducing speed also reduces motor cooling, unless the motor has a separate blower (as many inverter rated motors do). That is also that detail, which I probably chose to overlook before.

As speed increases over nameplate RPM, a motor running off of a drive changes from constant torque range to constant HP range & the torque available from the motor DOES reduce as speed continues to increase, due to current limiting from the drive. That IS a fact of physics. That is how drives are designed to work. Ask anyone who designs drives for a living.

I did not realize that his motor was 480. Since 480v 1 phase is not commonly available where 480 3ph is not present, & motors of that type probably don’t exist, than you are correct. The change is not as simple as adding a jumper. You got me on that one. Good catch.

I have run into harmonic issues in some of the more complex projects that I have been brought in on. I have had more than one instance in which adding a new drive into a system caused another drive to trip out, or sustain damage. Sometimes those two drives were in the same machine. Sometimes they were in different parts of the same building. Sometimes they were in different buildings in the same complex. This has happened to me with high end Japanese drives and top quality German drives. I don't have experience with the stuff that gets sold on Alibaba.

I normally spec my motors at or just above calculated load capacity & oversize my drive a bit above the motor size. I then limit the beating that the motor takes by programming the drive correctly. Correctly programmed drives generally still beat on motors in 3 ways. 1) The spike voltages are higher than nameplate voltage, which requires improved winding insulation to avoid Corona effect. 2) The carrier frequency is higher than nameplate frequency & causes increased mechanical cycling on the windings & accelerates stress fatigue. 3) when running a motor with an armature fan at reduced RPMs, you have reduced cooling. Drive rated motors are designed to handle these additional challenges. Standard motors, take it on the chin a little.

I have never ever seen a VFD used along with a soft start. Please let me know what kind of application used that combination. I would love to learn something new today.

I have added a VFD to an existing motor hundreds of times. It almost always works out, unless the application was marginal to begin with or the motor was really old or the motor was really beat. When I say old, I mean more than 50 years.

I think you misunderstood me. I DISallowed claims on improperly wired drives. I’ll have to go back & see if I was the victim of auto spell correct or if you misread what I wrote.

Of the drives I have seen, most that fail in the first few months, fail from improper usage. Most that don’t fail in the first few months, but do fail in the first 5 years, fail from overheating due to clogged fans. Most that fail after 10 years, fail from bad capacitors. It could be DC buss caps or the bypass caps inside the thyristor packs on the output stages. Buss caps are sometimes changed as a maintenance item. The bypass caps are usually potted inside the TRMs & are not accessible. That covers about ¾ of the failures that I have seen. I see drives from a wide variety of different industries, but mostly automated manufacturing equipment, elevators, robotics & machine tools. Compressor specific failures may be different.

If you’re in NJ, I’m going to guess that you probably get your drive repairs done by that place in Parsippany. I think it was either on Edwards Rd. or New Rd, but I haven’t dealt with them in many years, so I forget. I do remember their repairs generally being a little slower than the ones I did, back when I did that sort of thing as a sideline.

I agree that it is hard to justify loosing the benefits of 3 phase & changing to single phase.
….unless you have equipment that is already 3 phase & you need to use it someplace that only has single phase power available. I think that is what is being discussed here.

I think that I have sold a grand total of maybe 3 soft starts in my entire life. I mostly use drives. I sometimes use servos (which are actually just drives with feedback). I occasionally use phase inverters. I still use traditional contactors, when appropriate, too. My asking you to check on the constant frequency statement regarding the soft starts is based on that claim conflicting with the claims of a factory rep from S&S who later became a factory rep for Rockwell. He claimed that his soft starts were variable frequency. He twisted my arm to sell a couple of them many years ago. I’m not up on what is currently available. If you are confident of that claim, I’m ready to call my question answered, & thank you for confirming that information.

Regards,
the fish

We are not talking about the same harmonics, I think you are talking about electrical harmonics, I am talking about mechanical, that's why we aren't understanding each other.

Running off nameplate isn't an automatic recipe for disaster, unless you use variable closed loop control, if you are running steady state, chances are you picked an RPM that fine. Its one of those things you just never know so nameplate or OEM configured RPMs are best to stick with.

I do not have any off RPM operation wear data, the equipment I work on is usually 100HP+ duplex stuff with tons of controls, no one would dare run these at other RPMs since they cost more than a house and failures on these are always thoroughly investigated. I can tell you that operators that start/ stop too often, do incur massive maintenance costs.

I think on the torque to RPM thing, you are referring to the drive which as you say, HP remains constant for that device as RPM increases over nameplate, that's how I understand them to work. I was referring to the compressor's demand, which will require constant torque and increasing HP as RPM increases. I think we are both correct, just not both referring to the same thing.

I've never used a soft start with a VFD, maybe I mistyped or you misunderstood, as you know, a VFD is a soft start.

Adding VFDs to existing Non VFD applications is a big no no as far as I know. I may be skewed in that I work on stuff that usually has high starting parasitic loads and when they vary, the loads require constant torque which, in my experience always calls for a sizeable upsizing on the motor. I guess I can see a lot of applications where this would be fine, it just isn't in my world.

I did misread your warrantee claim statement, failures I see are same as you, caps failing or dirt and dust. I have had some where transistors just fell out of them which was interesting (and easily repaired. )

I agree 3 PH is always better (and cheaper) 1PH is for when you have to.

The soft starts I have encountered were sold as a variable frequency, I cant truly argue this since I haven't had an oscilloscope on them but the idea makes sense.

 

[PBcatfish]

Yeah that's it 8kw, have to get a bigger one it's a bit slow starting my 5.5kw Bauer mini verticus

If you put another 2Kw motor running on the roto gizmo before you start up the 5.5k load, the start up on the second load will probably have more snap. It sounds counter intuitive, but try it some time & see what happens.

 

[PBcatfish]

I am really enjoying the direction this went off topic. I am learning all kinds of new things.

I was thinking that a new thread should be started to ease up on the hijacking. Maybe I'll get to that tonight.