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From: hbg6@citek.mcdphx.mot.com
Newsgroups: sci.electronics
Subject: stepper current
Message-ID: <12471@qisoff.phx.mcd.mot.com>
Date: 26 Apr 91 14:50:47 GMT
Sender: listen@qisoff.phx.mcd.mot.com
Reply-To: hbg6@citek.mcdphx.mot.com
Organization: Motorola Microcomputer Division, Tempe, Az.
Lines: 24

How do you calculate the current drawn by a stepper motor.
Given the  (crude) illustration below. I measured the
current through the common lead of winding #1. ( .47A )
Is this the motor current as specified by motor drivers
or do you double it to account for winding #2 ?
Also, is the motor current as specified on the end of the
motor the current through one winding, one side of one
winding, or the sum of all of them?


  winding  --------     --
                   )  /    \
    1      --------  | rotor|
                   )  \    /
           --------     --
                       /\ /\
                      |  |  |
                      |  |  |
                      |  |  |
                   winding 2

I'd rather not figure this  out by "smoke-testing" several $185.00 motors!
Thanks,
John