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Startup Guide - May 2000
B-
63003EN-2/01
2
1
.
Look up the detection unit and flip it over to get the pulse count.
Let’s say that the customer specifies a detection unit of 0.05µm per pulse.
Flipping over
pulse
mm 0.00005
, we have
mm
pulses 20,000
mm 0.00005
pulse 1
=
.
2
.
Look up the LCI and flip it over.
The customer specifies a least command increment of 0.1µm per pulse.
Flipping over
pulse
mm 0.0001
, we have
mm
pulses 10,000
mm 0.0001
pulse 1
=
.
3
.
Plug the previous two values into eq. 2 and calculate CMR.
Plug in the values:
mm
pulses 20,000
CMR
mm
pulses 10,000
=×
Solving for CMR, we have CMR = 2.
Note
When you have determined the value of CMR, you must multiply it by 2 before
entering it into the servo setting screen. In this case, since we calculated our CMR to
be 2, we would have to enter the value “4” as the parameter.
4
.
Determine what kind of feedback you have and its resolution.
You can look for the motor number on the motor tag which is affixed to each GE
Fanuc motor.
Let’s say you read off the part number
A06B-0313-B072#7000
from the motor tag.
Looking this up in Chapter 2, Section 2 of the Servo Description Manual, you could
determine that the pulse coder’s resolution is
1,000,000 pulses
revolution
.