Air compressor 200hp

[dm9289]

We had a 100hp air compressor that went boom, contractor miss phased on plant outage.

We are considering a 200hp replacement we would have to rewire.

Should I simply size by 125% compressor name plate. Like a 430.22 single motor

Or do a multi motor calc for example 125% of 200hp motor + 100% of fan motor +100% of associated electronic for control boards

Thanks in advance

 

[infinity]

I don't see how you can use the single motor calculation when it has an additional fan motor.

 

[dm9289]

I don't see how you can use the single motor calculation when it has an additional fan motor.

I was meaning refer to entire unit rating as 1 motor

 

[hillbilly1]

With that large of a compressor, the manufacturer should be able to give you some guidance on the ocp. It probably has a soft start or reduced voltage starter.

 

[dm9289]

With that large of a compressor, the manufacturer should be able to give you some guidance on the ocp. It probably has a soft start or reduced voltage starter.

I think it’s going to be a star delta. We are scrambling for availability

 

[ptonsparky]

I was meaning refer to entire unit rating as 1 motor

You may. At 200 HP, a fractional hp fan won't add much.

 

[jap]

With that large of a compressor, the manufacturer should be able to give you some guidance on the ocp. It probably has a soft start or reduced voltage starter.

I would think so.

I would also think that an air compressor of that size would come as a packaged unit with it's own OCPD/Disconnect already installed to hit with a feeder.

JAP>

 

[augie47]

I would think so.

I would also think that an air compressor of that size would come as a packaged unit with it's own OCPD/Disconnect already installed to hit with a feeder.

JAP>

Agree....most, if not all, of the large compressors I dealt with had a factory specified main overcurrent device...often fusible.

 

[dm9289]

I would think so.

I would also think that an air compressor of that size would come as a packaged unit with it's own OCPD/Disconnect already installed to hit with a feeder.

JAP>

Yes it does hav OCPD but we will need to run new branch circuit to disconnect on wall before compressor then whip to compressor. Just scrambling to get a rough bill for install materials. Our plant has 2 compressor one is supplemental and runs about 30% of time. When we find a compressor available we will have to move very quickly. If we replace with 100hp no problem so far 200hp only one available instantly

 

[retirede]

You may. At 200 HP, a fractional hp fan won't add much.

If it’s a 200HP air-cooled screw compressor, the fan will likely be 3 to 5 HP.
The manufacturer should have a specified circuit and OCPD rating.

 

[hillbilly1]

We had a 100hp air compressor that went boom, contractor miss phased on plant outage.

We are considering a 200hp replacement we would have to rewire.

Should I simply size by 125% compressor name plate. Like a 430.22 single motor

Or do a multi motor calc for example 125% of 200hp motor + 100% of fan motor +100% of associated electronic for control boards

Thanks in advance

Hopefully the new one will have phase loss/reversal protection built in.

 

[zbang]

And if it's a screw compressor, it may have a VFD running things.

 

[dm9289]

Hopefully the new one will have phase loss/reversal protection built in.

I cannot believe this one did not it’s from 2018. That was very shocking to me.

 

[ptonsparky]

I cannot believe this one did not it’s from 2018. That was very shocking to me.

I dealt more with DIY, or others that just wanted things to run. So many times those options were turned off or never set up.

 

[augie47]

I dealt more with DIY, or others that just wanted things to run. So many times those options were turned off or never set up.

Pay me now, pay me later
sad !

 

[ptonsparky]

Pay me now, pay me later
sad !

I think I made more money fixing or diagnosing those screw ups than if I had done the projects to begin with.

 

[jap]

Yes it does hav OCPD but we will need to run new branch circuit to disconnect on wall before compressor then whip to compressor. Just scrambling to get a rough bill for install materials. Our plant has 2 compressor one is supplemental and runs about 30% of time. When we find a compressor available we will have to move very quickly. If we replace with 100hp no problem so far 200hp only one available instantly

You need the particulars on whatever it is that you are getting.

Generally on a compressor of that size they are self contained and you would be hitting a single point OCPD/Disconnect.

I'd find out what that is and prepare for that.

JAP>

 

[retirede]

You need the particulars on whatever it is that you are getting.

Generally on a compressor of that size they are self contained and you would be hitting a single point OCPD/Disconnect.

I'd find out what that is and prepare for that.

JAP>

For screw compressors, it’s not uncommon for the cooling module to be separate from the compressor itself. Very useful when the application includes heat recovery.

 

[jap]

For screw compressors, it’s not uncommon for the cooling module to be separate from the compressor itself. Very useful when the application includes heat recovery.

Agreed, but, all the advice in the world is not going to help him if it doesn't relate to what's actually going to show up.

Which we don't know.

JAP>

 

[dm9289]

Thank you for all your replies to an open ended question with many what ifs. It looks like we may have found a direct replacement one state away fingers crossed