For a 200 A feeder to a detached building you need two hots, a neutral and a separate equipment grounding conductor pulled through the PVC. Aluminum XHHW-2 is the right call here: it is rated for wet locations and conduit, and at 90 ft the voltage drop is small.
For a 200 A feeder to a detached building you need two hots, a neutral and a separate equipment grounding conductor pulled through the PVC. Aluminum XHHW-2 is the right call here: it is rated for wet locations and conduit, and at 90 ft the voltage drop is small. Use 250 MCM aluminum for the three current-carrying conductors (205 A at 75°C) and 4 AWG aluminum for the ground, which lands you around 1.3% drop at a full 200 A on 240 V.
250 MCM AA-8000 aluminum carries 205 A at the 75°C column, which covers a 200 A breaker without leaning on any exceptions. XHHW-2 is rated for wet locations, so it is legal inside underground PVC where water will collect. At 90 ft the drop is roughly 3 V at full load, about 1.3%, so you do not need to upsize for voltage drop.
90 ft run plus about 10 ft at each end for risers and panel makeup is 110 ft; add 10% and round up to 125 ft.
Also consider: XHHW 4/0AWG-RB is cheaper but rated 180 A at 75°C; some AHJs accept it on a 200 A breaker under the next-size-up rule if your calculated load stays under 180 A, but 250 MCM is the clean answer with headroom for the next ten years.
Same conductor as the black, in red so the two legs are identified at both panels without taping. Matching size on both hots keeps the drop balanced across the 240 V loads in the shop.
Same 110 ft plus 10%, rounded to 125 ft.
Also consider: XHHW 4/0AWG-RR, same trade-off as the black conductor.
A full-size neutral is the simplest way to satisfy the inspector and leaves you covered if the shop ends up heavy on 120 V loads like lighting, compressors on 120 V, and receptacles. Code lets you reduce the neutral based on calculated load, but on a 90 ft pull the savings are small compared to the argument you avoid.
Same 110 ft plus 10%, rounded to 125 ft.
Also consider: XHHW 4/0AWG-RW if you have a load calculation showing the neutral load is well under 180 A; saves a little money, but the 250 MCM neutral is the no-questions choice.
A feeder to a detached building has to carry an equipment grounding conductor, and NEC Table 250.122 calls for 4 AWG aluminum on a 200 A overcurrent device. Green XHHW-2 in the same conduit keeps the ground identified and wet-location rated like the rest of the pull. At a foot it is the cheapest conductor in the run.
Same 110 ft plus 10%, rounded to 125 ft.
Assumed: Single-phase 120/240 V, protected by a 200 A breaker at the main panel. The workshop is not a dwelling unit, so the 83% dwelling-feeder sizing that would allow 4/0 aluminum does not apply. Panel lugs at both ends are rated 75°C and marked for aluminum (AL9CU or similar). About 10 ft of extra conductor at each end for the conduit risers and panel makeup, on top of the 90 ft run.
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