Three Phase 50HP Motor Control

[Besoeker]

But a controlled starting ramp and active braking could both be advantages.

But until we know what it's actually driving we're into the realms of speculation.
Maybe the OP could step up to the plate and let us know what the specific requirements are. If an across the line starter was considered we might reasonably assume that's all that's needed.

More specific info needed.

 

[templdl]

But until we know what it's actually driving we're into the realms of speculation.
Maybe the OP could step up to the plate and let us know what the specific requirements are. If an across the line starter was considered we might reasonably assume that's all that's needed.

More specific info needed.

I agree. The only thing that I can think of and would bring up for consideration is a possible voltage sage as a result of across the line starting. You have to admit though that it is fun to keep on guessing until we get lucky in finding an answer to an application that we have no idea as to what it is.

 

[Besoeker]

I agree. The only thing that I can think of and would bring up for consideration is a possible voltage sage as a result of across the line starting. You have to admit though that it is fun to keep on guessing until we get lucky in finding an answer to an application that we have no idea as to what it is.

Fun indeed. But not productive.........

 

[ptonsparky]

?...You have to admit though that it is fun to keep on guessing until we get lucky in finding an answer to an application that we have no idea as to what it is.

Akin to being in trouble with the spouse and have no idea what you did or if it is even your fault.

 

[kwired]

But as has already been mentioned if ramping up to speed is the only feature needed a soft starter would cost less then a VFD and get the job done.

 

[templdl]

Akin to being in trouble with the spouse and have no idea what you did or if it is even your fault.

That's why by keeping ones mouth shut maybe, just maybe you will get lucky enough later and not be assigned to sleeping on the couch .

 

[templdl]

Akin to being in trouble with the spouse and have no idea what you did or if it is even your fault.

That's why by keeping ones mouth shut maybe, just maybe you will get lucky enough later and not be assigned to sleeping on the couch .

 

[topgone]

That's why by keeping ones mouth shut maybe, just maybe you will get lucky enough later and not be assigned to sleeping on the couch .

Hahaha. I pity you guys!

 

[powerplay]

Have a few suppliers coming up with pricing for motor starter (not a controller), which appears to be the across the Line starter with overloads. I got one price back for approximately $700 including an remote stop/start button for the Operator of the Sawmill if we simply use available 120 volt power for control circuit.

Today we sourced out used equipment, and have come across an old Square D Starter that may fit the bill, only it has what appears to be old Overloads marked "CC81.5" which I will need to source out to protect the 63 FLA at 1.15 service Factor. The real question is how reliable is it after being outside in an unheated storage container for a long period of time...

 

[powerplay]

Generally, changing speed on a saw is not a good idea. Saw blades are designed for a specific operating speed, as in how fast the cutting teeth move across the material. Changing that speed can result in poor performance and even dangerous consequences.

The Brother in Law is an Engineer that is helping design it I hear, and I think they are setting up the RPM with Pulleys to keep the speed the same..

 

[Jraef]

Have a few suppliers coming up with pricing for motor starter (not a controller), which appears to be the across the Line starter with overloads. I got one price back for approximately $700 including an remote stop/start button for the Operator of the Sawmill if we simply use available 120 volt power for control circuit.

Today we sourced out used equipment, and have come across an old Square D Starter that may fit the bill, only it has what appears to be old Overloads marked "CC81.5" which I will need to source out to protect the 63 FLA at 1.15 service Factor. The real question is how reliable is it after being outside in an unheated storage container for a long period of time...

What can happen to an improperly stored motor starter like that is that the pole faces of the electromagnet inside of it can get rusty. That will make it hum and maybe chatter, which can lead to early failure.

But with any used motor starter, you have no idea of HOW it was used, or more importantly, ABused. For all you know, the contacts might be burned already, or so badly damaged they will fail in short order. If you have to ask all of these questions, I'd venture to say you don't have a lot of experience with motor controls, so having you disassemble and inspect the contacts might be pointless. My advice would be to do it right, and do it once, by using a properly sized new starter this time. Trying to save money using used parts is something more experienced electricians gan get away with, but is not something I suggest for beginners. There is nothing more expensive than a part that has to be installed twice.

By the way, that heater element is for 49.1 to 61.2A FLC in a Size 3 starter (which I assume is what you have). It's a little shy of your motor FLC if it is 63A. Not inherently dangerous, but you will not be able to get full capacity from your motor without risking tripping it. The next size up is a CC103.0, which covers 61.3 - 77A. I would use that one if you are going to take a chance with that used starter.

 

[Johnnybob]

Depends on the driven load. Is it a set of chains than needs speed control? Or a belt? We have VFDs on our twin resaws.

 

[Johnnybob]

Depends on the driven load. Is it a set of chains than needs speed control? Or a belt? We have VFDs on our twin resaws.

Twin resaw feed rolls, that is!:dunce:

 

[powerplay]

What can happen to an improperly stored motor starter like that is that the pole faces of the electromagnet inside of it can get rusty. That will make it hum and maybe chatter, which can lead to early failure.

But with any used motor starter, you have no idea of HOW it was used, or more importantly, ABused. For all you know, the contacts might be burned already, or so badly damaged they will fail in short order. If you have to ask all of these questions, I'd venture to say you don't have a lot of experience with motor controls, so having you disassemble and inspect the contacts might be pointless. My advice would be to do it right, and do it once, by using a properly sized new starter this time. Trying to save money using used parts is something more experienced electricians gan get away with, but is not something I suggest for beginners. There is nothing more expensive than a part that has to be installed twice.

By the way, that heater element is for 49.1 to 61.2A FLC in a Size 3 starter (which I assume is what you have). It's a little shy of your motor FLC if it is 63A. Not inherently dangerous, but you will not be able to get full capacity from your motor without risking tripping it. The next size up is a CC103.0, which covers 61.3 - 77A. I would use that one if you are going to take a chance with that used starter.

Thanks for your advice... I have suggested going new, but he is assuming cleaning up the rust will prevent the chatter. yes I have little Motor Control experience and have suggested the return on the Investment is invaluable for reliable work with less likely unwanted down time, but the Sawmill Operator seems convinces cleaning it up will work... we will be running up the setup with the brother in law who is an Engineer that I assume will not want to refurbish the parts.

Any idea how much the CC103.0 Overloads cost and how available this technology is?

 

[powerplay]

Depends on the driven load. Is it a set of chains than needs speed control? Or a belt? We have VFDs on our twin resaws.

he has Belts driven by a diesel motor... He says he wants simple on and off... but it sounds like he wants to see the amps being drawn to determine how much stress is on the blade (Band) VFD is probably the way to go...

 

[kwired]

Thanks for your advice... I have suggested going new, but he is assuming cleaning up the rust will prevent the chatter. yes I have little Motor Control experience and have suggested the return on the Investment is invaluable for reliable work with less likely unwanted down time, but the Sawmill Operator seems convinces cleaning it up will work... we will be running up the setup with the brother in law who is an Engineer that I assume will not want to refurbish the parts.

Any idea how much the CC103.0 Overloads cost and how available this technology is?

CC series melting alloy overloads are still used on new products. Solid state overloads are sort of taking over but you can still order motor starters with melting alloy overload assemblies.

CC series fits size 3 and 4 contactors. Look at the chart that should be inside the enclosure to select your unit. They do use different selection table depending size of enclosure, number of thermal elements, and other factors that can effect overall heating in that enclosure. If you don't have a selection table you can go to their online digest and find the proper selection table for your application.

 

[Jraef]

CC series melting alloy overloads are still used on new products. Solid state overloads are sort of taking over but you can still order motor starters with melting alloy overload assemblies.

CC series fits size 3 and 4 contactors. Look at the chart that should be inside the enclosure to select your unit. They do use different selection table depending size of enclosure, number of thermal elements, and other factors that can effect overall heating in that enclosure. If you don't have a selection table you can go to their online digest and find the proper selection table for your application.

the CC103.0 should be readily available at any decent Square D distributor for anywhere from $20-30 each, you will need 3.

If your starter only has two, then it is too old to be used legally. The requirement for 3 came about in the mid 1970s, so if there are only two, it gives you an idea of just how old that starter is.

You can get any number of Current Monitor Relays that can give you an output telling you what the load is on the motor, no need for VFD to get that. But a 50HP resaw is something I personally would start with a solid state soft starter, not across the line. The hard jerking start from across the line is something that will cause problems in the long term with the mechanical components, especially if it has been driven by an engine up until now. The power that an electric motor puts onto the belts and shafts is instantaneous, which is never the case with an engine drive. I've seen many machine changeovers that have resulted in serious damage because people don't realize that.

 

[powerplay]

the CC103.0 should be readily available at any decent Square D distributor for anywhere from $20-30 each, you will need 3.

If your starter only has two, then it is too old to be used legally. The requirement for 3 came about in the mid 1970s, so if there are only two, it gives you an idea of just how old that starter is.

You can get any number of Current Monitor Relays that can give you an output telling you what the load is on the motor, no need for VFD to get that. But a 50HP resaw is something I personally would start with a solid state soft starter, not across the line. The hard jerking start from across the line is something that will cause problems in the long term with the mechanical components, especially if it has been driven by an engine up until now. The power that an electric motor puts onto the belts and shafts is instantaneous, which is never the case with an engine drive. I've seen many machine changeovers that have resulted in serious damage because people don't realize that.

Thanks again for the feedback! The Starter has three, but is missing the reset button.

It sounds like we have better have a solid state soft starter... is that another term for VFD?

 

[GoldDigger]

Thanks again for the feedback! The Starter has three, but is missing the reset button.

It sounds like we have better have a solid state soft starter... is that another term for VFD?

It is a simpler device with some but not all of the functions of a VFD. Therefore less expensive and fewer points of failure.

 

[kwired]

Thanks again for the feedback! The Starter has three, but is missing the reset button.

It sounds like we have better have a solid state soft starter... is that another term for VFD?

It is a simpler device with some but not all of the functions of a VFD. Therefore less expensive and fewer points of failure.

And not designed for more then a short duration of reduction of output - after the starting period is ended it is essentially in a bypass mode and motor is running across the line. All that is actually varied is startup and sometimes shutdown.