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The US electrical system
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TimFox:
Electricity and plumbing is not a trivial problem.  During the American invasion of Iraq, faulty grounding caused over 18 accidental electrocutions of Army and contractor personnel in new showers.  See
https://www.huffpost.com/entry/toll-rises--at-least-18-u_b_124863
When installing equipment in foreign countries with temporary portable Diesel generators for AC mains, I encountered ungrounded three-wire outlets.  Since all our low-power equipment used a conventional 3-prong IEC line filter at the single-phase mains input, the chassis of computers or other equipment ended up near half the mains voltage with respect to the heavy hardware that was grounded.  Even though the current through the victim is limited by the small capacitance of the filter, it can still cause one to fall off a ladder when surprised.
AlbertL:
Figure 1-1 ("Multi-Grounded Common Neutral" Distribution System) on this page https://www.electrical-contractor.net/forums/ubbthreads.php/ubb/printthread/Board/15/main/16309/type/thread.html illustrates the system used by my utility, and which I think is the most common in the US.

So, here's a question: what would be the resulting voltage at the customer's premises (bottom of the drawing) in the case of an accidental short between the ungrounded side of the distribution transformer primary (7200V) and one end of the 240V secondary?

duckduck:

--- Quote from: NiHaoMike on June 28, 2020, 12:50:31 pm ---
--- Quote from: tooki on June 28, 2020, 08:40:07 am ---Non-heat-pump condenser dryers use more energy than vented, not less: https://www.cda.eu/laundry/condenser-vs-vented/

--- End quote ---
In cold climates, vented dryers are the least efficient after accounting for heat lost from the building.

--- End quote ---

In cold climates all appliances are 100% efficient ;)
CatalinaWOW:

--- Quote from: duckduck on June 30, 2020, 11:34:25 pm ---
--- Quote from: NiHaoMike on June 28, 2020, 12:50:31 pm ---
--- Quote from: tooki on June 28, 2020, 08:40:07 am ---Non-heat-pump condenser dryers use more energy than vented, not less: https://www.cda.eu/laundry/condenser-vs-vented/

--- End quote ---
In cold climates, vented dryers are the least efficient after accounting for heat lost from the building.

--- End quote ---

In cold climates all appliances are 100% efficient ;)

--- End quote ---

Not an outside vented cloths dryer.
helius:

--- Quote from: AlbertL on June 30, 2020, 09:49:04 pm ---So, here's a question: what would be the resulting voltage at the customer's premises (bottom of the drawing) in the case of an accidental short between the ungrounded side of the distribution transformer primary (7200V) and one end of the 240V secondary?
--- End quote ---
Which end, the side linked in-phase with the primary, or the other side?
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