Making electrical wire longer

[WinterDeere]

While not mentioned there, anything over 48VDC is also considered high-voltage, as it can kill.

It probably depends on who is doing the classification. In the controls industry, it is possible some companies or societies may define 48VDC as "high voltage", but in the utility industry anything under 1000 volts is typically termed "low voltage".

The basic structure of voltage classifications remains consistent across most standards, though there can be slight variations in voltage ranges depending on specific documents or standards. The widely accepted classifications are as follows:

• Low Voltage (LV): ≤1 kV
• Medium Voltage (MV): >1 kV to <100 kV
• High Voltage (HV): 100 kV to <230 kV
• Extra High Voltage (EHV): ≥230 kV to <1 MV
• Ultra High Voltage (UHV): ≥1 MV

These classifications are used globally and provide a foundation for electrical systems design and equipment manufacturing. However, certain standards may vary based on regional or safety considerations.

Voltage Classifications Explained: What They Mean and Why They Matter | Mission Critical Engineers

Discover the basics of different voltage levels and how they impact safety and efficiency in everyday electrical systems.

missioncriticalengineers.com

 

[Oaktree]

While not mentioned there, anything over 48VDC is also considered high-voltage, as it can kill.

It probably depends on who is doing the classification. In the controls industry, it is possible some companies or societies may define 48VDC as "high voltage", but in the utility industry anything under 1000 volts is typically termed "low voltage".

Don't many jurisdictions require you to be a licensed electrician if you're working on voltages higher than 48V? ISTR recall reading something to that effect when hybrid cars first came along.

 

[ultrarunner]

I have knob and tube wiring and so far the 1922 work is holding up well... all soldered splices.

 

[WinterDeere]

Don't many jurisdictions require you to be a licensed electrician if you're working on voltages higher than 48V? ISTR recall reading something to that effect when hybrid cars first came along.

At least in PA, as far as I know, there is never any requirement to be licensed to work on any voltage. However, there are contractor licensing requirements if you call yourself an electrician or charge for services. And because only licensed contractors get to work on utility systems, that circuitously covers them at those voltages.

I've spent most of my career working on high voltage hardware, and while we as a company had training requirements, that was a matter of controlling our own liability and safety, and not a matter of licensing requirements.

Ever seen someone shock themselves on a 40,000 volt DC power supply? I have! And I'm not talking about wimpy low-current TV tube supplies, either... these were capable of delivering 50,000 watts or more.

 

[RayIN]

At least in PA, as far as I know, there is never any requirement to be licensed to work on any voltage. However, there are contractor licensing requirements if you call yourself an electrician or charge for services. And because only licensed contractors get to work on utility systems, that circuitously covers them at those voltages.

I've spent most of my career working on high voltage hardware, and while we as a company had training requirements, that was a matter of controlling our own liability and safety, and not a matter of licensing requirements.

Ever seen someone shock themselves on a 40,000 volt DC power supply? I have! And I'm not talking about wimpy low-current TV tube supplies, either... these were capable of delivering 50,000 watts or more.

 

[Oaktree]

Ever seen someone shock themselves on a 40,000 volt DC power supply? I have! And I'm not talking about wimpy low-current TV tube supplies, either... these were capable of delivering 50,000 watts or more.

Not quite to that extreme, but I've worked on plenty of broadcast transmitters. RF burns are nasty too, don't ask how I know...

 

[WinterDeere]

yep. Cooked myself a few times. I spent most of my career designing high power RF and microwave amplifiers, but more for testing applications than for broadcast. Similar power levels, since the military customers in particular wanted to test high field strengths over large areas (e.g. an entire flight squadron in formation). The test equipment is designed to work over broad frequency ranges, so they can test all the different threats in a given standard or protocol, whereas the broadcast equipment only had to work over the narrower range that was being broadcast from a given antenna.

 

[404nouser]

Not quite to that extreme, but I've worked on plenty of broadcast transmitters. RF burns are nasty too, don't ask how I know...

I never got burned but my wallet got microwaved and my cards quit working.
It was only a 2 megawatt burst for about 20-30 seconds from a disconnected waveguide on a s band radar.

 

[LD1]

Need a little more detail about the OP's situation to best answer. But in general....no dont splice it in conduit.

Direct burry secondary wire wire gets spliced from time to time if its NOT in conduit. They have special splices made for it. Basically a barrel/set-screw type splice with a seal patch that goes over it. Full of sticky sealing stuff. But not for use in conduit.

Lots of ways to probably do what the OP is wanting, but without further detail of the project, its hard to advise

 

[WinterDeere]

I never got burned but my wallet got microwaved and my cards quit working.
It was only a 2 megawatt burst for about 20-30 seconds from a disconnected waveguide on a s band radar.

That's a heck of a lot of power in S-band. Depending on distance and duty cycle, you were likely shooting blanks for awhile, and may have suffered some liver damage. Testes and liver are almost always the first to cook due to HERF exposure.