
B–63503EN–1/01
9. SPINDLE SPEED FUNCTION
369
Keep in mind the following: Even with bit 7 (TCW) of parameter No.
3706 = 1, the CNC cannot determine the output polarity if it has not issued
M03/M04, and therefore, actual output does not work even if the speed
command output has been specified.
According to the speed command output and the polarity determined so
far, the command is sent to the spindle control unit as follows:
⋅ For serial spindle → Digital data 0 to"16383
⋅ For analog spindle → Analog voltage 0 to"10 V
After power is switched on, a nonzero command is output to the spindle
only when the following conditions are met: A nonzero spindle speed
command is specified, and the output polarity is determined.
With bit 7 (TCW) of parameter No. 3706 = 1, no command output is sent
to the spindle, because the output polarity is not determined until an
M03/M04 is issued.
The command output to the spindle is reset to 0 when a command to
specify so (such as *SSTP = 0 or S0 command) is issued.
M05, emergency stop, or reset does not cause the CNC to reset the
command output to the spindle to 0.
Another output related to spindle control is the spindle enable signal
ENB.
The ENB signal is logical 1 when a nonzero command output is sent to
the spindle. If the command is logical 0, the ENB signal becomes logical
0.
When the analog spindle is being used, an offset voltage in the spindle
motor speed amplifier may cause the spindle motor to rotate at low speed
even if the command output (in this case, analog voltage) to the spindle
is zero. The ENB signal can be used to stop the motor in such a case.
The analog spindle may require gain and offset voltage adjustment
depending on the spindle motor speed amplifier being used.
The following parameters are available for such adjustment.
Gain adjustment data: Parameter No. 3730
Offset voltage compensation: Parameter No. 3731
The signals related to analog spindle interface are described below.
The ENB1 and ENB2 signals are turned on and off under the same
condition as for the ENB signal <F001#4>. They can be used also for the
serial spindle.
D Command output to
spindle
D Requirement of output
D Requirement to stop
output
D Spindle enable signal
ENB <F001#4>
D Gain and offset
D Electrical specification
of analog spindle
interface