Delta Tau Geo MACRO, User Manual And Reference Manual

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Geo MACRO Drive User and Reference Manual
Appendix D 191
Now that we know how to step through electrical cycle, we must determine the location and values of the
Hall Effect Transitions. Typically, there are two different locations for the transitions:
0
o
60
o
120
o
180
o
-120
o
-60
o
30
o
90
o
150
o
-150
o
-90
o
-30
o
To determine where the transitions occur, drive the motor to electrical zero by issuing the following
command:
P179=I179 P129=I129 ; store previous offsets before test
#1o0 ; for motor 1- #2 for motor 2 etc…
I179=3000 I129=0 ; 0
o
elec.
Then write the phase position to 0 and turn off the current to the motor by:
M171=0
I179=P179 I129=P129 ; restore previous offsets after test
#1k
Now that the motor is killed, rotate the shaft through the electrical cycle looking for a change of state.
Once we find the location where the halls change state, we can calculate where in the electrical cycle we
are by the following formula:
Electrical Cycle Degrees = M171/I171*360
It might be easier to write a short PLC that stores the electrical cycle location similar to the following:
OPEN PLC 2 CLEAR
P171=M171/I171 *360
CLOSE
Now put P171 in a watch window and determine one of the transition points. Now all transition points
should be known and thus be able to determine where the Hall Effect Sensors are located.
0
o
60
o
120
o
180
o
-120
o
-60
o
; Hall Sensors at 30
o
, 150
o
, and 270
o
30
o
90
o
150
o
-150
o
-90
o
-30
o
; Hall Sensors at 0
o
, 120
o
, and 240
o
Example 1 of Hall Effect Values
Turbo PMAC Hall Effect Example with Ixx72=683 Hall Sensors at 30
o
, 150
o
, and 270
o
For the Turbo PMAC, the Hall effect method of phasing uses two PMAC I-Variables, Ixx81 and Ixx91.
Ixx81 tells PMAC what address to read for absolute power-on phase-position information, if such
information is present. Ixx91 tells how the data at the address specified by Ixx81 is to be interpreted.
M124->X:$78000,20 ;W channel 1
M125->X:$78000,21 ;V channel 1
M126->X:$78000,22 ;U channel 1
M127->X:$78000,20,4 ;T,U,V,W channel 1