junkhound
Senior Member
- Location
- Renton, WA
- Occupation
- EE, power electronics specialty
A recent question by an apprentice got me to thinking:
How old were you when you understood what a switch was?
Thought to recall some of these for myself, as to understand the perspective of a grandkid or 20-something apprentice or even a retired engineer.
A contactor or relay ?
DIfference between parallel and series connections.
An SCR ?
A VFD?
How a delta-wye transformer works?
High voltage
Best of my recollection:
Switch - prior to learning to read
relay - cub scouts, about 8 YO
Parallel series - good example of ignorance. About 8 YO also, had a box full of expired 6 V lantern batteries, knew the 'textbook' definitions, but not practice. Hooked ten in paralle, good power to car headlight. Pop said series ws to connect +_ to minus in a string - I took the parallel set I had lined up on the table and turned every battery 180 deg so + to -, etc = you guessed it hot batteries due to short circuits.
SCR - about 12 YO, first one I got was totally amazed at how it acted like a latching relay with no moving parts!!!
VFD - college prof in 1964 has a research project for primitive motor drive
delta-wye; already had BSEE and in my 20s before I realized how the triplett harmonics short circuit in a delta primary.
high voltage: had gotten shocks ( tingle) from record player numerous times before 6 YO. At 8 YO thought to take back off B&W tube TV (were there any other kinds in the mid 50s?) and found out about HV when I got burnt by plate electrode on 6BQ6.
How old were you when you understood what a switch was?
Thought to recall some of these for myself, as to understand the perspective of a grandkid or 20-something apprentice or even a retired engineer.
A contactor or relay ?
DIfference between parallel and series connections.
An SCR ?
A VFD?
How a delta-wye transformer works?
High voltage
Best of my recollection:
Switch - prior to learning to read
relay - cub scouts, about 8 YO
Parallel series - good example of ignorance. About 8 YO also, had a box full of expired 6 V lantern batteries, knew the 'textbook' definitions, but not practice. Hooked ten in paralle, good power to car headlight. Pop said series ws to connect +_ to minus in a string - I took the parallel set I had lined up on the table and turned every battery 180 deg so + to -, etc = you guessed it hot batteries due to short circuits.
SCR - about 12 YO, first one I got was totally amazed at how it acted like a latching relay with no moving parts!!!
VFD - college prof in 1964 has a research project for primitive motor drive
delta-wye; already had BSEE and in my 20s before I realized how the triplett harmonics short circuit in a delta primary.
high voltage: had gotten shocks ( tingle) from record player numerous times before 6 YO. At 8 YO thought to take back off B&W tube TV (were there any other kinds in the mid 50s?) and found out about HV when I got burnt by plate electrode on 6BQ6.