please help - common voltages

[neukammd]

I've got a question for all you smart power people: Someone approached me & asked what are the most common AC & DC voltages and cycles (Hz). I know of a few:

5V DC
12V DC
24V DC

110V AC
220V AC
440V AC

50 Hz
60 Hz
400 Hz

Are there any other common voltages? They were especially asking about 270V. Would that be AC or DC???

Thanks so much for any help.

 

[Rocketir]

I'll assume you mean low voltages only.
we have the following transformer secondary voltage levels.

120/240 VAC
120/208 VAC
240/480 VAC
277/480 VAC



Jasjit Khangura P.E.
Electric Distribution Engineer

 

[cuky2000]

Many frequencies had been used in the past such as 25, 30, 40, 50, 60, 66.667, 83.33, 125, and 133.33Hz. Some of those still remain in service as follow:

25 Hz could be found in old power distribution systems or in rail application.
91.66 Hz signal power application on one the mass transportation in the US East Coast.

For DC system it is common to have 600 Vdc and 650 Vdc for third rail applications.


Few nominal standard voltages around the world for LV power distribution applications are:
190/110
200/100
200/115
210/105
220/110
220/127
230/115
346/200
380/220
400/230
415/240
440/220

 

[alehman]

48V DC is normal for telecommunications equipment
125V DC is common for switchgear control power
480V DC is used for large UPS systems

These are nominal voltages. Actual systems typically run a little higher.

 

[081066]

I came across to 277V AC. I beleive it is one of the volatges used in USA. However, apart from volatge levels mentioned already here by other people, 6 kV ( in mining industry), 11 kV, 22 kV all AC are also used in some European countries.