Fagor 8035-T - Spindle in Closed Loop

 Installation manual
CNC 8035
5.
CONCEPTS
Spindle
(SOFT M: V15.3X)
(S
OFT T: V16.3X)
·230·
5.9.4 Spindle in closed loop
One of the following conditions must be met in order for the spindle to operate in closed loop by
means of "spindle orientation (M19)":
• It is an analog or digital drive with feedback to the CNC (via connector) and s.m.p NPULSES
(P13) is other than 0.
• It is a digital drive (CAN) with feedback to the drive and s.m.p DRIBUSLE (P51) is other than 0.
Also, when switching from open to closed loop, either an "M19" or an "M19 S±5.5" must be executed.
The S±5.5 code indicates the spindle position, in degrees, from the spindle reference point (marker
pulse).
When switching form open to closed loop, the CNC behaves as follows:
• If the spindle has a home switch:
In this case, it is possible to detect the right reference mark among the possible ones (having
the encoder at the motor) originated especially by different gear ratios.
In order for the drive to detect the right reference mark, the home switch detection must be
accurate. This is achieved by having the spindle turn one more revolution once the home switch
has been detected. The end portion of this last spindle revolution is carried out slowly.
Spindle home search:
The spindle must have an encoder so it can be homed.
Once the home switch has been detected, the spindle will keep turning in the same direction
and at the speed indicated by s.m.p. REFEED1 (P34). Before completing the next 350º, the
spindle slows down to the speed indicated by s.m.p. REFEED2 (P35). From then on, the home
switch is detected while turning at REFEED2 speed and keeps moving until detecting the
reference mark.
Some points to consider:
 The first movement until the home switch is detected and the entire next process is carried
out in the direction indicated by s.m.p. REFDIREC (P33).
 The home search may be started when the spindle is stopped or moving (M3 or M4). If the
home search starts when the spindle is stopped or it has to change its turning direction, the
transition from the starting speed S0 to the one indicated by s.m.p. REFEED1 will be made
with a linear acceleration ramp.
 If the home search starts when it is stopped and the home switch is pressed, it will also turn
one more revolution.
 This type of spindle home search may be carried out with a CAN drive. In order for it to work
on CAN or analog spindles when there are several reference marks per revolution due to
different gear ratios, the reference mark must be managed with the DECELS signal ignoring
the actual (real) reference mark signal.
For greater accuracy, if the average cycle of the PLC exceeds 8 ms, we recommend to
manage the DECELS input at the PLC with a periodic cycle equal to or shorter than 8 ms.
It is also recommended to manage the DECELS input from a local input.
From versions V15.11 (mill model) and V16.11 (lathe model) on, it is possible to apply
a derivative gain or feed-forward while homing the spindle.
i
REFEED1
350º
REFEED2
I0
DECELS