De-rate on outlet

Chris_Keziah said:
This is wrong on so many levels, speed of the motor has nothing to do with quality.
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The quality of the compressor, not the quality of the motor. Shitty compressors use 3500 rpm motors. Nice ones (like Andrew probably has at work) are more likely to be 1750.
 
shawn said:
The quality of the compressor, not the quality of the motor. Shitty compressors use 3500 rpm motors. Nice ones (like Andrew probably has at work) are more likely to be 1750.
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The most logical reason for shitty compressors using 3500 rpm motors is the fact they're single stage compressors and the more expensive being dual stage.


Back to the orginal comment though it really relies on what industry you're looking at as to what speed motors are most commonly used.
 
shawn said:
The quality of the compressor, not the quality of the motor. Shitty compressors use 3500 rpm motors. Nice ones (like Andrew probably has at work) are more likely to be 1750.
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Some of that is to reduce pump head RPM, which reduces noise (a LOT) and increases pump head durability (among other benefits). I usually shop for compressors based on pump RPM for that very reason. It also means the pump head has to have higher displacement for a given output flow, which makes the pump head bigger and more expensive.
 
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Chris_Keziah said:
The most logical reason for shitty compressors using 3500 rpm motors is the fact they're single stage compressors and the more expensive being dual stage.
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Nah, I have a single-stage at the house that runs at 1750. It's a Speedaire, and it's designed to be quiet and last a long time.

Fabrik8 said:
Some of that is to reduce pump head RPM, which reduces noise (a LOT) and increases pump head durability (among other benefits). I usually shop for compressors based on pump RPM for that very reason. It also means the pump head has to have higher displacement for a given output flow, which makes the pump head bigger and more expensive.
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Shorter fabrik8: shitty compressors use small displacement pumps and spin them twice as fast to get the spec numbers up, which reduces pump life to somewhere just the far side of the warranty period. Nice compressors use big-displacement pumps and spin them slower.

I think somebody already said that about 10 posts ago, though. :flipoff2:
 
Just try it. It will probably work fine.
 
With belt drive you'll be able to change pulley size to get the correct rpm for the pump/motor combination.

You should not have to shroud the motor to keep the water out. If you losing that much water at the pump them you have other problems.
 
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