Motor sizing

[greenelec]

Hi I have 2 sumps on my farm that pump manure out of a milking pit. The current sumps are both rated at 1/2hp but can't seem to keep up so we are upgrading to two 2hp pumps. Currently the motors are 120V and fed from 2 15A breakers.

The two options for new pumps we are looking at are;
-208V 3phase (Canada) with a full load amperage of 10.6A or
-575V 3phase (Canada) with a FLA of 4.9A.

I have 2 spare 15A breakers in a 600V CDP approx 30m away if we go with 600V pump or else I will re-connect to the 2 15A breakers we are using for the existing motors if we go with 208V.

Now that the background is out of the way my question concerns wiring. I am pretty sure I got a handle but want to confirm. Based on table 1 CEC I can run a 3C#14AWG which is good for 20A at 75degC (ie 600V 4.9A*1.25=6.125A). That 20A rating is for the entire load correct? Or each individual conductor? The second part of my question is what type of wire is recommended? The original installation in plastic pipe but I am not sure what type of wire was used? Is there a requirement for type of wire if everything is installed liquid tight? I was planning on using THHN or RW90.

 

[jumper]

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