Results 1 to 9 of 9
Thread: motor rpm
-
04-09-2010, 01:28 AM #1
motor rpm
Can somebody tell me what the 120 in motor rpm calculations is? rpm= 120xhz/#of poles
-
04-09-2010, 01:36 AM #2
-
04-09-2010, 02:48 AM #3
Re: motor rpm
yes,rev's per min
-
04-09-2010, 03:06 AM #4
Re: motor rpm
the synchronys speed factor for 3 phase motors.
-
04-09-2010, 01:26 PM #5
Re: motor rpm
Speed of rotation is:
Number of current reversals per minute / number of poles
For a 1 HZ cycle of a sine wave there will be 2 reversals, this will occur once a second. So to get it to minutes (remember we are after Revs per Minute) 2 x 60 = 120
Cheers,
Andy.Health and safety first..........unless I'm in a hurry.
-
04-09-2010, 02:31 PM #6
-
04-09-2010, 05:24 PM #7
- Join Date
- Sep 2007
- Location
- Split Croatia
- Age
- 57
- Posts
- 6,151
- Blog Entries
- 6
- Rep Power
- 36
Re: motor rpm
That number is constant in connection with seconds to minute conversion (as Tayters alredy explained).
If you using other formula with number of pairs of poles, that constant is 60 (seconds).
S = f60/p
where: S = rotor speed in rpm (revolutions per minute)
f = AC line frequency
n = number of pairs of polesLast edited by nike123; 04-09-2010 at 05:58 PM.
-
04-09-2010, 05:50 PM #8
- Join Date
- Sep 2007
- Location
- Split Croatia
- Age
- 57
- Posts
- 6,151
- Blog Entries
- 6
- Rep Power
- 36
-
04-09-2010, 08:17 PM #9
Re: motor rpm
So, one who used "120" (60 sec multiplied by 2) was speaking about number of POLES in the formula,
if one prefers PAIRS of POLES, then just 60 would be used.