3 ms·

Large factories can get 480V 3 phase power in the US, but even laundries and restaurants get 240V “split phase” which is technically still single phase, just tw

Large factories can get 480V 3 phase power in the US, but even laundries and restaurants get 240V “split phase” which is technically still single phase, just two power lines that would normally be going to two houses instead going to the same place. We have a very wonky power grid here due to how early on it was built. The rest of the world had the ability to see our mistakes and fix them after WW2.

rsynnott 6y ago
I'm not sure if it's age so much as bad (in the long run) choices at the time. European power grids have been around for a while (and some have their own oddities; the historical use of ring circuits in UK and Ireland domestic installations produced lasting weirdness, for instance).
frosted-flakes 6y ago
That's not quite correct. Any building in an industrial area could conceivably get three-phase power if it's on the poles along the road, not just large factories. My friend owns a small manufacturing shop (probably 6k to 8k square feet with less than 10 employees), and he has three-phase power. Also, all buildings in the US/Canada have split phase power, not just businesses like laundromats and restaurants. Split phase is one of the three 240 V phases split into two 120 V lines. Electric ranges, dryers, and baseboard heaters in residential buildings commonly use 240 V by utlizing both 120 V lines.
Obi_Juan_Kenobi 6y ago
This is incorrect. Nearly all transmission and most distribution in the US is done with three phases. Commercial and industrial access to three phase is very common, though this will vary by region/utility. Residential access is less common, but not that unusual. In some places, you just call up the utility, tell them what equipment you'll be using (i.e. what amperage you'll require) and provided it's enough demand to justify it, they'll run the lines at no or minimal cost. Residential split phase is usually based on pole-mounted transformers that serve a limited number of customers. They are, themselves, operated off the three-phase distribution.

rsynnott 6y ago

I'm not sure if it's age so much as bad (in the long run) choices at the time. European power grids have been around for a while (and some have their own oddities; the historical use of ring circuits in UK and Ireland domestic installations produced lasting weirdness, for instance).

frosted-flakes 6y ago

That's not quite correct. Any building in an industrial area could conceivably get three-phase power if it's on the poles along the road, not just large factories. My friend owns a small manufacturing shop (probably 6k to 8k square feet with less than 10 employees), and he has three-phase power. Also, all buildings in the US/Canada have split phase power, not just businesses like laundromats and restaurants. Split phase is one of the three 240 V phases split into two 120 V lines. Electric ranges, dryers, and baseboard heaters in residential buildings commonly use 240 V by utlizing both 120 V lines.

Obi_Juan_Kenobi 6y ago

This is incorrect. Nearly all transmission and most distribution in the US is done with three phases. Commercial and industrial access to three phase is very common, though this will vary by region/utility. Residential access is less common, but not that unusual. In some places, you just call up the utility, tell them what equipment you'll be using (i.e. what amperage you'll require) and provided it's enough demand to justify it, they'll run the lines at no or minimal cost. Residential split phase is usually based on pole-mounted transformers that serve a limited number of customers. They are, themselves, operated off the three-phase distribution.