Tagged Questions
0
votes
1answer
535 views
How to calculate voltage drop over and power loss in wires
How do I calculate the voltage drop over wires given a supply voltage and a current? How do I anticipate on voltage drop so that the final load has the correct supply voltage?
What will be the power ...
0
votes
1answer
109 views
Suitable wiring for very low current mains equipment
I'm building an interactive portrait gallery with seventy portraits, each back-illuminated by an LED lamp. The lamps draw less than 30 mA at 230 Vac, and each is switched using a small ...
0
votes
0answers
104 views
skin and proximity effect for solid cables
I am just wondering how to compute the skin and proximity effect for solid cables. The ks and kp values in the table here:
Table
are 'just' for stranded cables etc. Thanks.
2
votes
1answer
79 views
volumetric specific heat of insulation
Could anyone please be so kind and point me to a relevant lookup table please? I did some google searches but could not find anything. Thanks a lot.
5
votes
2answers
557 views
Why do thunderstorms knock out power?
It isn't like lightning strikes the wires. And surely the whole apparatus is designed to be water-proof. So what is it that causes power outages during thunderstorms?
3
votes
2answers
415 views
Thermal time constant, thermal resistance, thermal capacitance
Where does the thermal time constant, thermal resistance and thermal capacitance in IEC standard 60853-2 come from (e.g. section 4.1.4)?
They are used to determine the partial transient of a cable.
...
1
vote
1answer
209 views
LV cable sizing for short circuit condition (NEC)
Do we need to perform short circuit condition i.e let through energy condition while sizing the LV cables as per NEC (National Electrical Code)?
3
votes
1answer
160 views
Design considerations for powering microcontrollers with a 100 m cable
I'm currently doing some research for a project where I'd have a number of microcontrollers (say 5 ATtinys or if I manage to bring power consumption down, maybe even ATmegas) which I want to power ...
3
votes
3answers
238 views
Why ship a low power charger with an overkill thick cable?
Today I saw a Sony camera charger that claimed to provide 8.4V/1.7A output but had a cable going to the device being powered with 18AWG (0.824mm2) cross-section and insulation rated at 300V (yeap, ...
5
votes
1answer
606 views
What should I know about interference between wires in a multi-conductor cable?
I want to use a multi-conductor cable for a few different circuits. What do I need to know about interference between circuits within a multi-conductor cable?
Some of the wires will carry stepper ...
3
votes
2answers
181 views
cable jacket melts
I am new to hardware.
My breadboard just arrived and I am trying to light up my LED. I used computer power supply for power (red wire for + black for -) and used strands of LAN cable for connect LED ...
