
B-63192EN/03 9.TRACING CONTROL
- 57 -
9.1.3 Tracing Speed
On receiving an analog signal from the detector, the CNC subtracts
the reference deviation E0 from it and multiplies the difference by
loop gain K to calculate the speed command for the Z-axis. The loop
gain can be specified using a parameter.
Vz = 60 × K (E-E
0
)
where V
z
= Z-axis speed (mm/min)
K = tracing loop gain (typically 30 sec
-1
)
E = input deviation (mm)
E
0
= reference deviation (mm)
The normal gap deviation (∆E = E-E
0
) for tracing control is calculated
as follows:
∆E = (V
xy
× tan θ) / (60 × K)
where ∆E = normal deviation (mm)
V
xy
= X-Y plane feed command (mm/min)
θ = tilt from the X-Y plane (°)
K = tracing loop gain (typically 30 sec
-1
)
9.1.4 Tracing Gain Override
Override can be applied to the tracing loop gain over a range between
12.5% and 100% in 12.5% steps.
9.1.5 Command
(1) Programmed start and stop
The tracing function can be turned on and off using the G
CODE.
G13 P_ ; Tracing start command
P : Reference deviation (in 0.001mm increments)
G14 _ ; Tracing end command
(2) Start and stop controlled by an external signal
The tracing function can be turned on and off using a signal from
the PMC.
NOTE
The tracing function cannot be turned on and then
off by a combination of a G code and external
signal. Use the same type of commands to turn on
and off the tracing function.