How to safely use a 100V appliance in a home with 120V power.

Ian0

Joined Aug 7, 2020
9,680
I come across them often enough - some snake-oil salesman got them installed in public buildings as a power saving device; and they play havoc with the emergency lighting systems as the mains voltage is permanently hovering around the "mains fail" threshold for emergency lighting; but they weren't called "buck boost transformers"
 

MaxHeadRoom

Joined Jul 18, 2013
28,621
The ones I often used were simple step down transformers which when used in this fashion, were commononly referred to as either Buck or Boost depending on method used.
 

Ian0

Joined Aug 7, 2020
9,680
Where did we get the term “buck”? Is it a male rabbit or deer, or a dollar, or bucking the trend, or bucking like a mule? (though that seems more apt to describe a fly back converter)
 

MaxHeadRoom

Joined Jul 18, 2013
28,621
Where did we get the term “buck”? Is it a male rabbit or deer, or a dollar, or bucking the trend, or bucking like a mule? (though that seems more apt to describe a fly back converter)
One is most likely to relate a particular definition based on their particular work environment, custom of use and experience, for me, it was known as a common term in powering various industrial electrical/electronic devices .
In this respect, it is a perfectly viable description.
 

phonetagger

Joined Aug 2, 2022
1
You will also need to re-reference the earth ground conductor to one side of the secondary to replicate the grounded neutral.
You can make either secondary terminal a neutral.
You will then have two conductors at this terminal, one a neutral conductor, the other the ground.
I feel like this is bad advice. A neutral should never be bonded to ground except at the primary service panel that connects to the outside power service. If you're using an isolating transformer, then one side of the secondary should be tied to the neutral on the primary side (in order to allow GFCI/AFCI breakers to detect leakage current). If your service has a neutral conductor, and if you're using a buck/boost transformer, the series buck/boost add/subtract should be on the line side, leaving the neutral connected straight through from the line side to the load side. At no point in this arrangement should any neutral conductor or any transformer tap be connected to ground. If the transformer has a chassis ground connector, that is the only thing that should be connected to ground. (Except the ground pin of this arrangement's output socket; of course that should also be connected to the input ground conductor, just as a pass-through.)
 

MaxHeadRoom

Joined Jul 18, 2013
28,621
I feel like this is bad advice. A neutral should never be bonded to ground except at the primary service panel that connects to the outside power service
It is explained in NFPA79 and shown diagrammatically.
This mainly occurs in industrial systems where the control enclosure or system is fed with 3ph HV and the 120v control voltage is derived from a 440v/120v 1ph transformer.
In this case, the reference to earth ground has been lost and requires to be re-referenced, This method has been used for many decades in N.A..
It has lost favour now due to the advent of using 24vdc Control voltages.
 

Halfpint786

Joined Feb 19, 2018
109
All you need for rice is a pan with a lid. Follow these instructions exactly.

1) Put rice and water in pan (no preheating the water).
2) Turn on heat to high
3) Stir occasionally until boiling so nothing sticks
4) As soon as it starts boiling, give it one last stir, cover with lid, then set stove heat to simmer. The simmer should be just enough to keep a small wisp of steam escaping from the pan lid, it shouldn't be boiling and making the lid hop. It doesn't take much heat here.
5) Set the timer and wait. DO NOT TOUCH THE LID UNTIL STEP 7! Do not stir, do not peek, do not even think about checking on it. JUST LEAVE IT ALONE!
6) After the timer beeps, turn off the heat and let it sit just like that to steam an additional 5 minutes. Do not remove the lid to stir or check on it, you want the steam to stay in there for 5 more minutes!
7) Uncover and enjoy.

The amount of water and time depend on the rice.
Long grain white = 1 cup rice, 2 cup water, 18 minutes on timer.
Short grain white = = 1 cup rice, 1.25 cup water, 15 minutes on timer.
Brown = = 1 cup rice, 1.75 cup water, 45 minutes on timer.
 
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