Low/high voltage and in between

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croecken

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I found a definition for low voltage (110.26A1a), for high voltage and only for that Article (490.2), is there a standard accepted label for in-between? Like more than 50V and less than 600V.
 
I believe it is all relative to what voltages you are usually working with. If I am working with 120/240 then 24 volts is low voltage. If you are on a 480 volt system you may consider 240 volts low voltage. Generally speaking the code usually breaks it down 0-600 volts. or over 600 volts. The nec does define low voltage or high voltage per se. At least its not in the definitions
 
Sure, the first section that comes to mind is Article 110 Section II 600 Volts or less and Section III Over 600 Volts. Was this a test????
 
Dennis Alwon said:
Generally speaking the code usually breaks it down 0-600 volts. or over 600 volts.
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I am not trying to imply that low volt is under 600 volts and high voltage is over 600 volts. I am merely stating that the code reference Under 600 volts and over 600 volts many time throughout the code.
 
croecken said:
I found a definition for low voltage (110.26A1a), for high voltage and only for that Article (490.2), is there a standard accepted label for in-between? Like more than 50V and less than 600V.
Click to expand...

As several have said, it is all relative. I have been used to calling 0-1000 low voltage, 1kV to 70kV medium voltage, and 100kV and over high voltage. If you look at offerings of switchgear of folks like GE, Siemens, Schneider, and Cuttler Hammer, these fit in their product ranges.

I further separate POWER from CONTROL; the above are power. With very few exceptions, control in the USA is under 250V, most often 120VAC, 24VAC, or 24VDC.

We further see limited energy stuff like thermostats, alarm, networking, CATV, speakers which may be millivolts to 70V (speaker systems).
 
Part X of Article 250 considers high voltage as anything over 1,000V.

In all honesty, low voltage doesn't really mean anything, because it is used in context. The real issue, in my opinion, is power limiation. For example, in a wet location, 15V is considered lethal. The same 15 volts in a power limited circuit is not. Take a look at the notes to Table 11 if you are bored.
 
No not a test but to make a point, it was made following your post. Seems to me the 600 volt division has more to do with equipment. Often the hi or lo has to do with safety.
 
Years ago I worked for a testing company, the technician I worked for called over 1000 VAC real voltage and below 1000 VAC wirenut voltage.
 
Thanks for all the input, this was not a test. I've been asked to review my companies electrical maintenance procedures and I had a slight problem with the labeling of one procedure. Namely Low Voltage Electrical Safety which they describe as 60-600Vac. I just wanted to make sure the code didn't have a label for this range.
 
Most contractor insurance policies limit coverage to 600-volts and less. If you are going to work on voltage higher than 600-volts you will need a different insuance policy. Check with your insurance company.
 
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