Voltage Drop and wire size

[ebasista]

I have the chance to pick up some 4/0 SE cable cheaply....only problem is I cant put wire into my home panel that thick.

I'm only looking at running 100A in my garage, can I run this cable between my garage panel into a disconnect and downgauge at the disconnect into my main panel and have it breakerred for the lowest gauge? Will this also help with voltage drop, or will it all be based on the lowest gauge as well (assume 200ft on the 4/0 and 20ft on say 2awg to tepanel

 

[malibu101]

Without going into detail, yes you can safely do what you propose and it wiill help with voltage drop over that distance.
A little detail--
SE cable is usually 2 conductors with the "neutral" wrapped around them. Read as 3 wires.
What you are proposing is a subpanel. Subs need 4 wires. The 2 hots and a seperate neutral and seperate ground back to the main panel.

 

[ebasista]

My mistake....this is three conductor plus ground.

 

[malibu101]

My mistake....this is three conductor plus ground.

Good deal.
If the cheap price of the SE cable offsets the cost of a 100A fusible disconnect-Go for it.
You are set!
EDIT- Of course you are using the SE cable in a approved manner?????

 

[Aceman]

I think you'd be better off selling it and buying #2 SER. 4/0 SER is a bear to work with, it doesn't bend easily and you have to holesaw large holes through framing members just to get it to pass through. Not worth the trouble IMO...

 

[mrb]

you dont even need to use a disconnect switch for the transition, you can simply use some polaris blocks or other splice methods.