All Questions
59
questions
8
votes
9
answers
9k
views
Is Ohm's law really accurate?
Say I had a component with a resistance of 100 Ω, and I attached a 12 V power supply across its terminals using:
a thin wire
a thick wire
Would the component in both cases really draw (12 V/100 Ω) A?...
- 133
0
votes
3
answers
260
views
Voltage-current relationship in the wire
I'm reading Art of Electronics by Paul Horowitz and Winfield Hill. Although it is a well-written guide to electronics, I'm stuck with the first topic.
I would appreciate any answer that can help me to ...
1
vote
1
answer
2k
views
What determines the voltage rating of a cable, and why do some cables have \$U_0 = U\$ while others have \$U_0 < U\$?
Just as an example, let's consider two cables, with voltage ratings being respectively 300/300 V and 300/500 V.
My understanding is that voltage rating is an indication of the quality of the ...
0
votes
2
answers
103
views
"Wired" indoor/outdoor thermometer
Will doubling the original 9' length of (I think it is 28 gauge) low-voltage wire to the outdoor sensor affect thermometer performance? I've noticed that after some time, I get funky readings.
It ...
1
vote
2
answers
242
views
Wire gauge sizing & current values [duplicate]
While working on selections of wire, I was introduced to the "current rating" of wires. Is this current rating dependent on voltage as well?
Example: A 10 AWG wire is rated to handle up to ...
- 11
6
votes
5
answers
3k
views
Is the bigger wire section always better from the electrical point of view?
A bigger wire section is better for lowering power loss and voltage drop due to lower cable resistance.
Is there any case or application where using a wider cable section is worse?
(Exclude mechanical ...
- 269
2
votes
2
answers
3k
views
Difference in wire gauge for three phase and single phase domestic power supplies
I'm trying to understand why the recommended wire gauge for a domestic supply depends on whether you're getting three phase or single phase power. Specifically I'm talking about when the power rating ...
- 21
-1
votes
2
answers
270
views
Can I power a 35 Watt light fixture over a thermostat 5-wire?
I would like to add this light fixture to my ceiling in an area that only has a thermostat 5-wire coming out (something like this). (The other end of the thermostat wire travels about 15 feet, ending ...
- 1
0
votes
2
answers
55
views
Do current limits apply just the same on lower voltage?
Do current limits also apply on lower voltage?
For example:
I have a wire/fuse that is rated for 2A. I usually runs it at 10VDC. Then, I use 5VDC with 3A load. Will the fuse blow?
- 159
0
votes
0
answers
89
views
Power 100+ 5v LED matrices
I'm trying to power over 100 LED matrices laid out in a long, single chain similar to a stock ticker on news buildings. I do have the control part figured out but bringing power to the matrices is ...
- 11
2
votes
4
answers
6k
views
Should negative and positive wires be of same length?
Do positive and negative wires need to be of same length all the time for a circuit to run smoothly? Of course same gauge but only different lengths.
What would be its effect on the system if we say ...
0
votes
1
answer
844
views
Maintaining constant voltage at end of long wire
I have a long 1 mm wire, about 1.5 meters long (and 1.5 m back). At the end of a wire I have a device that requires 3.7 V and can pull anywhere from 0 to 6 A at a time. However, when it pulls a high ...
- 143
0
votes
4
answers
2k
views
Can we possibly have too large wire to drop voltage over a long distance?
I had a argument with a friend about whether how can we possibly have too large wire gauge?
Assumption 1. The voltage will never drop over a long distance (200 feet) because the wire is too large. No ...
0
votes
3
answers
1k
views
Can FFC/FPC connectors use in high voltage but lower current applications?
product page
FVMC 0.2 mm pitch connector supports 50V 200mA which is 10 Watt power,
my application 100V 8mA, can I use above connector in my application since wattage is 0.8 Watt
- 194
0
votes
3
answers
784
views
12V 20A: What to do for high heat
I have 4 DC motors. they each require about 12V 9A DC (108W each), and have a potential draw of up to 12V 20A each (240W each) stall current.
I am using 22 AWG insulated wire. The length of the wire, ...
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