Commissioning
Instruction manual 91/121 V6.3
•
If you use an analog input to change the torque limit, you must connect the shielded cable to the analog input 2 of the drive
(see section “Connector X11” on page 18), to enable the function and select the source of the torque limit reference value use
the parameter ”Torq. Lim. Source“ on page 47 among the available sources.
•
The torque limit can be adjusted with the analog input 2 or with one of the internal analog references that can be set with the
menu ”Analog Reference“ on page 50.
•
In the menu “Advanced Setup → Aux Functions → Ext Torque Limit → Limit Output” if the function is active, you can see
the current value of the torque limit. If the function is not active, this parameter will always be 99.99 % and will not change
even by changing the associated analog input.
The scale of this torque limit is as a percentage of the maximum torque of the motor. If the analog input has the standard gain values
(Gain) the value of 10Vcc on the terminals corresponds to the maximum torque of 100 %; in proportion, a voltage of 5Vcc on the ter-
minals corresponds to 50 % of the maximum torque. As always, you can change the scale of the analog input to adapt it to the signal
(see section ”Analog input X“ on page 40).
5.6.8 Anti-backlash system
5.6.8.1 Generality
The task of the electric anti backlash is to eliminate the mechanical play present in the kinematic chain when gearboxes and sprocket-
gear groups are used. The electric anti backlash uses two equal units, each consisting of a drive and an electric motor. The two drives
ensure that the torque generated by the two motors is equal but of the opposite sign. In this way the gear teeth are in contact and the
kinematic chain plays are cancelled. When the system is in motion the torque dispensed by one motor increases while that of the other
diminishes keeping the play of the kinematic chain always null. The anti-backlash system uses two equal drives (same rated current).
One drive is called
Master
and the other
Slave
. The
Master
drive receives all the controls from the outside and controls the system
while the
Slave
drive is driven by the
Master.
5.6.8.2 Connection diagram
1. Follow the connection scheme of Drawing 1 on page 11 (for THREE-PHASE power supply) or as indicated in Drawing 2 on
page 12 (for DC BUS D.C. power supply) with regard to the connection of the motor, the transducer, the power supply auxil-
iary services and possibly the external braking resistance for both the MASTER drive and the SLAVE drive.
2. For links specific to the anti-backlash system, please follow Drawing 22 on page 65. All commands and signals coming from
the CNC or PLC must be connected exclusively to the MASTER drive. The DOK and RDY signals must be used in the
MASTER drive.
3. Connect DC+ and DC- of the MASTER drive with the corresponding DC+ and DC- of the SLAVE drive, as shown in Draw-
ing 22 on page 65. In the case of three-phase power supply the power cables must be connected to the L1-L2-L3 terminals as
indicated in the drawing, in the case of direct power supply on the DC-BUS these terminals must remain empty.
4. Connect the MASTER and SLAVE drives with a twisted cable inserted on the X7 connectors of the two drives, as indicated
5. Fuse backhoes indicated with F2 and F3 should be sized following Table 2 on page 7 (with “ultra rapid” fuses). The fuse tern
indicated with F1 must be sized to protect cables from overload (no need for “ultra rapid” fuses).
6. The “Network Filter” and the L1 Inductance shall be sized at a value equal to the sum of the nominal currents L1-L2-L3 of
the two drives as shown in table 2 on page 7.
7. The line switch indicated with K1 can only be closed if the DOK output of the MASTER drive is +24Vcc.
64
Alter Elettronica s.r.l.
