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I have a 3HP 3phase 230/460V motor for a through the wall exhaust fan.
Whoever installed the motor they just connected to the switch(L1,L2,'L3 to T1,T2,T3)
Under the diagram it says "Use a manual momentary start switch only".
Now I tested the 3 wires on the LINES and I have a 220v and a neutral
When I turn on it doesn't work... If the one that aperently is the neutral I ground it it works...
But I think is on a low voltage diagram because the motor stars really slow...

IM NOT A MOTOR MAN,

It comes from timer to the motor.....
Any suggestion? How can I make it work... Properly?
 

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Enanosky44 said:
I have a 3HP 3phase 230/460V motor for a through the wall exhaust fan. Whoever installed the motor they just connected to the switch(L1,L2,'L3 to T1,T2,T3) Under the diagram it says "Use a manual momentary start switch only". Now I tested the 3 wires on the LINES and I have a 220v and a neutral When I turn on it doesn't work... If the one that aperently is the neutral I ground it it works... But I think is on a low voltage diagram because the motor stars really slow... IM NOT A MOTOR MAN, It comes from timer to the motor..... Any suggestion? How can I make it work... Properly?
That's funny, were is your journeymen?
 

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Post the motor's peckerhead so we can see how it is wired up. When someone asks me to troubleshoot a motor I always first check the voltage going to the motor (to see what the voltage is, to look for a dead leg, etc) then I check the way the peckerhead is wired. 99% of the time one of those two is the source of issues on a newly installed motor that I have to troubleshoot.

"The switch is most likely the code required motor disconnect."

It's not a disconnect, it's a push button of some kind.
 

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Don't understand why it would say only use manual momentary switch. Is it saying you are required to use a starter with a momentary start switch?
I assume it says that meaning you can only use a motor latching circuit with the motor, or something similar. That's how I read it at least, but every motor I have installed has had either a motor starter or a latching circuit of some kind.

This is the manual for his motor, if anyone is interested:
http://www.baldor.com/support/Literature/Load.ashx/MN408?ManNumber=MN408
 

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I have a 3HP 3phase 230/460V motor for a through the wall exhaust fan.
...
Now I tested the 3 wires on the LINES and I have a 220v and a neutral
When I turn on it doesn't work... If the one that aperently is the neutral I ground it it works...
Discussing the the part of this that is about the type of switch is like discussing the upholstery on the lifeboats of the Titanic. There is a MUCH bigger problem going on here...
 

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JRaef said:
Discussing the the part of this that is about the type of switch is like discussing the upholstery on the lifeboats of the Titanic. There is a MUCH bigger problem going on here...
But the Titanic's lifeboats didn't sink.
So it's all good right?
 

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I'm sort of stabbing in the dark here, but I get the idea that the switch is actually a magnetic starter with separate 120AC control and the neutral of the control circuit is open.

This would explain why it works when the white is grounded; the ground is the return path for the coil neutral.

Don't read too much into this, it's a pretty wild guess........
 

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I'm sort of stabbing in the dark here, but I get the idea that the switch is actually a magnetic starter with separate 120AC control and the neutral of the control circuit is open.

This would explain why it works when the white is grounded; the ground is the return path for the coil neutral.

Don't read too much into this, it's a pretty wild guess........
With the limited information about what kind of switch he is dealing with, I think that is a pretty good guess. And maybe the motor is wired for the high voltage which is why it starts really slow.

I think Baldor is saying to use a motor starter vs. a manual switch so the thermostat leads (J) can shut it down if the motor overheats.
 

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8V71 said:
With the limited information about what kind of switch he is dealing with, I think that is a pretty good guess. And maybe the motor is wired for the high voltage which is why it starts really slow. I think Baldor is saying to use a motor starter vs. a manual switch so the thermostat leads (J) can shut it down if the motor overheats.
That's how I've wired them. Other installs used the leads on the momentary side of the starter circuit. If it's open in the motor it won't allow the contactor to pull in.
 

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With the limited information about what kind of switch he is dealing with, I think that is a pretty good guess. And maybe the motor is wired for the high voltage which is why it starts really slow.

I think Baldor is saying to use a motor starter vs. a manual switch so the thermostat leads (J) can shut it down if the motor overheats.
I agree this would be the proper way to do it but it is a bit confusing when it says on the motor to use only a manual momentary switch.
 

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I agree this would be the proper way to do it but it is a bit confusing when it says on the motor to use only a manual momentary switch.
I find the wording strange also. But if you think about it, unless you want to hire a guy to keep the button pushed in all day long, it's really saying to have a magnetic contactor with a seal in. Maybe something got lost in the translation. :laughing:
 

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Hey kinda the same topic. I have a motor that has a nameplate 208v-230v/460v. I understand the low voltage and high voltage but does the 208-230 mean it can take both? In the lower voltage connection in can take either 208 or 230?


Sent from my iPhone using Tapatalk
 

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Bilge Rat
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Hey kinda the same topic. I have a motor that has a nameplate 208v-230v/460v. I understand the low voltage and high voltage but does the 208-230 mean it can take both? In the lower voltage connection in can take either 208 or 230?


Sent from my iPhone using Tapatalk
Yes, it'll run on either 208 or 240, same connection.
 
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