new compressor is installed at work, how long will it last is the question

nickb2

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thx for that bill, it puts things into perspective.

But dang, that thing howls
Annoying to say the least.

 

billr

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What is that white ball??? It looks cotton.

Do you have the acoustic enclosure?
 

nickb2

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No, we are building it our selves. Blew out a few holes already in the white cinder block wall, but we are so swamped right now, we dont have time to finish the enclosure, for now the entrepot guys just deal with the noise with some ear buds.
 

billr

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I got it now. That is a cotton ball... your present sound control system.
 

NickD

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London and Australia is 50 Hz, Canada like the US is 60 Hz and reading 50 Hz on your name plate. If Tesla only selected 120 Hz, he was no good at math, motors and transformers could be 1/4 the size.

Applying 60 Hz to a three phase motor is not too bad, will run faster, but due the higher impedance, less power. But running a 60 Hz motor at 50 Hz is far worse, not only slower, but the current draw is much greater, over heating the motor.
 

nickb2

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London and Australia is 50 Hz, Canada like the US is 60 Hz and reading 50 Hz on your name plate. If Tesla only selected 120 Hz, he was no good at math, motors and transformers could be 1/4 the size.

Applying 60 Hz to a three phase motor is not too bad, will run faster, but due the higher impedance, less power. But running a 60 Hz motor at 50 Hz is far worse, not only slower, but the current draw is much greater, over heating the motor.
Yeah, like I wrote, that thing runs real hot.

But mostly, the guys are just not liking it cuz it never shuts off. It really hums and has an annoying kinda whine to it.

When down time comes around, we will get the enclosure done. @ Nickd, I am not seeing 50hz on name plate, I am seeing 60hz. But does it really matter?
 

NickD

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5 and a 6 are rather similar, put my magnifying glass on my hi res monitor, it is a 6. But 575 volts is awfully weird, for three phase, more common in the US is 240 or 440 VAC .

Another problem with three phase is you have three wires 120 electrical degrees, like 120, 240, 360, at times have to use a scope and the motor wires have to be in proper sequence.

If its wired for 120, 360, 240, motor won't know if its coming or going. Try to run forward, but when that phase is reversed, will jerk backwards, at 60 cycles per second.

That motor is also under constant load driving that compressor, a good motor has zero DC resistance, because current flow through resistance creates heat, so what limits the current flow is what is called generator action in a motor, the voltage is such that is generated opposes the applied voltage. So if the applied voltage is too low, motor does not reach operating speed, induced opposing voltage is low, differential voltage is high, so not reaching full speed, and the motor with excessiver current will get red hot.
 
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