- #31
zoobyshoe
- 6,506
- 1,254
That is an interesting anecdote, but I'm confused about how the car started with only the + terminals connected.
Bring 12V DC Home: An Idea to Reduce Transformer Clutter
- Thread starter WarrickF
- Start date
-
- Tags
- Dc
Click For Summary
Discussion Overview
The discussion revolves around the idea of implementing a 12V DC power system in homes to reduce the clutter of individual transformers for electronic devices. Participants explore the feasibility, safety, and practicality of such a system, considering both historical context and modern technological advancements.
Discussion Character
- Exploratory
- Debate/contested
- Technical explanation
Main Points Raised
- Some participants propose that a 12V DC system could eliminate the need for individual transformers, making home electronics more streamlined.
- Others suggest that a higher voltage, such as 18V or 24V, might be more effective for modern devices.
- Concerns are raised about the safety of DC compared to AC, with some arguing that DC is more dangerous due to its inability to "let go" during an electric shock.
- One participant argues that voltages below 50V are generally not harmful, while another counters that the danger of electrocution depends on the current, not just the voltage.
- There is a discussion about the practicality of changing home wiring standards and the potential costs involved in transitioning to a DC system.
- Some participants highlight the existence of various DC devices that operate at different voltages, questioning whether standardizing to 12V is feasible.
- Technical details are shared regarding the efficiency of DC-to-DC converters compared to AC-to-DC converters, with some noting the advantages of smaller, more efficient components in DC systems.
Areas of Agreement / Disagreement
Participants express a mix of agreement and disagreement regarding the safety and practicality of a 12V DC system. While some see potential benefits, others raise significant concerns about safety, cost, and the feasibility of standardizing voltages for various devices. The discussion remains unresolved with multiple competing views presented.
Contextual Notes
Participants note that historical standards for home wiring were established before the advent of modern microelectronics, which complicates the transition to a DC system. Additionally, there are unresolved questions about the safety of low-voltage DC and the implications of changing existing electrical infrastructure.
Who May Find This Useful
This discussion may be of interest to electrical engineers, home automation enthusiasts, and individuals involved in the design and implementation of electrical systems in residential settings.
- #32
GENIERE
zoobyshoe said:
The touching bumpers provide the ground path. Must have been older type cars that had metal bumpers. Drag might have been embarresed if the bumpers had welded together!
Last edited by a moderator:
- #33
zoobyshoe
- 6,506
- 1,254
I didn't take the "touch bumpers" literally, but of course, that makes perfect sence.GENIERE said:
- #34
kleinjahr
- 74
- 0
It takes about 6 milliamps to cause serious harm. Doesn't matter if it's AC/DC, the CURRENT not the voltage, that will make you rock.
- #35
govinda
- 13
- 0
integral ,
i had the same doubt zooby had about the frequency being generally high and therefore not giving u enough time to remove ur hand . isn't it more realistic to consider the average over half a cycle (.707 times the maximum) for each direction?
also i didnt quite understand what u meant by muscles alternatively flexing and distending?
i had the same doubt zooby had about the frequency being generally high and therefore not giving u enough time to remove ur hand . isn't it more realistic to consider the average over half a cycle (.707 times the maximum) for each direction?
also i didnt quite understand what u meant by muscles alternatively flexing and distending?
- #36
whozum
- 2,219
- 1
I remember when I wired my house for ethernet, a friend of mine dared me to lick my fingers and touch the bare phone wires. I was terrified of the 46V, but when I finally did it it was merely a tickle.
- #37
krab
Science Advisor
- 892
- 3
Yeah. I'm dating myself here. This was 26 years ago, when practically all cars had these heavy chrome-plated steel bumpers.GENIERE said:
- #38
zoobyshoe
- 6,506
- 1,254
If there were any truth to this it would only result in vibration of the muscles at 60hz with very low amplitude.govinda said:
- #39
govinda
- 13
- 0
zooby ,
im sorry still don't understand what's going on with the muscle care 2 elucidate?
im sorry still don't understand what's going on with the muscle care 2 elucidate?
- #40
zoobyshoe
- 6,506
- 1,254
I think what Integral is saying is that once you become part of a direct current circuit, at sufficient voltage, it is the current itself that won't let you go.govinda said:
From that, he argues that AC is safer because it changes direction 120 times a second and there is a point 120 times a second when the current going through you is 0 amps at 0 volts, which, he contends, gives you the chance to pull yourself out of the circuit.
My contention is that the current causes a person to clench their muscles, and it is this clenching that prevents people from getting themselves out of electric circuits, rather than being held prisoner by the current.
Dave is the one who brought up the part about flexing and extending. I think it was just speculation on his part. It takes a small amount of time for a muscle to relax once it has been clenched, and I know a human muscle can't fully relax from being clenched in 1/120th of a second. The most you might get is a vibration.