Design/drawing package layout for large motor installation

Thread Starter

Igyneous

Joined Nov 24, 2011
3
What's a good resource to help determine what to include in a design/drawing package for a new 2500 HP motor installation including power supply design (transformers, switch gear, protection & controls, drives, and physical layouts)? What would an acceptable drawing package include?
 

MisterBill2

Joined Jan 23, 2018
11,888
The motor manufacturer will probably be able to recommend suitable controls, and the controls supplier will certainly be able to recommend the controls arrangement.
AND, unless you are creating this installation for your own entertainment, the customer should be able to describe what they want. If none have such requirements then you are all in far over your heads. OR just out of school and just got a serious engineering position.
 

MisterBill2

Joined Jan 23, 2018
11,888
Probably the actual power wiring drawings will be needed. Besides that, presuming the motor will run on a higher voltage, a whole safety study will need to be included.
 

Thread Starter

Igyneous

Joined Nov 24, 2011
3
The motor manufacturer will probably be able to recommend suitable controls, and the controls supplier will certainly be able to recommend the controls arrangement.
AND, unless you are creating this installation for your own entertainment, the customer should be able to describe what they want. If none have such requirements then you are all in far over your heads. OR just out of school and just got a serious engineering position.
Thanks for your suggestions. These are good points.
 

MrSalts

Joined Apr 2, 2020
1,762
Thanks for your suggestions. These are good points.
If you have a budget for a 2500HP motor and you don't know where to even get software to make a specification drawing, it's time to hire an engineering company to do it for you. Who knows, the investment in trained contract engineers with all the right tools may pay for itself in the short term or long term.

Imagine what size cables you'll need for full load of a 2500HP (2 Megawatt) motor. Unless your project is a drop-in replacement, you'll have to talk to the power company about a new substation - the power company may have to run a new set of power lines if your not in an industrial zone that has sufficient power lines near by. You'll likely need 6kV lines to the motor - my guess, check with the mfg, of course. I'm guessing a new 2MW motor will be $750k to $3M depending on features and the size of a small truck.
 
Last edited:

MisterBill2

Joined Jan 23, 2018
11,888
This certainly will be a quite large motor, and so depending on what it will be driving there will need to be a complete mechanical drawing package as well, unless it is indeed a replacement for an existing motor, or a system upgrade, which I doubt.
So the initial drawings will need to include the foundation to support both the motor and the machine it is driving. That is a task for an industrial architect that understands foundations. Then a drawing showing the motor in the installed position. and probably including a bit of the machine, as the coupling will be quite a chunk of metal and need a hoisting system to install. This package should also include the related mechanical systems to show the completed installation.
The electrical connection cabling will need both an electrical circuit, with specifications, and mechanical details showing the path from the motor to the starting switch-gear enclosure. Probably the switch-gear supplier can provide that drawing package.. The connections between the controls section and the switch-gear package will also need to be shown. Some details of the control and monitoring systems will certainly be required.
Depending on what part of the world this is located in, drawings showing the guarding and safety arrangements may also be required. And in California certainly an environmental impact document will be mandatory.
In all probability a layout and details of the power station serving this motor will also be required, although the power company may be providing that portion of the drawings. Certainly a layout and details of the feed from the substation to the switch-gear will be required.

And now my questions: What voltage is the motor supply? And what sort of device is such a large motor driving? My guess is either a pump or a blower/fan of some large proportion. The one large package that I quoted used an array of six 100HP motors driving hydraulic pumps in parallel. This was done for several reasons, first, to allow adjustment of the system power based on the loading at the time, then, also to reduce the starting power requirements, and finally, to make future replacement of pumps or motors much simpler. It also greatly increased system availability since five pumps could provide most of the flow when running at maximum output. Yes, it was a bit conservative design, per customer requirements.
 
Top