Digital I/O; Using A Digital Input As A Drive Enable Input (Optional); Using A Digital Input As A Home Switch Input (Optional); X4: Digital Inputs - Safe Torque Off (Sto) Inputs - ABB MicroFlex e190 User Manual

64 Electrical installation: input / output

Digital I/O

The MicroFlex e190 provides:
• 4 general purpose digital inputs.
• 2 dedicated Safe Torque Off (STO) inputs.
• 3 general purpose digital outputs.
6 additional general purpose digital inputs and 4 additional general purpose digital
outputs can be provided by the option card (see page 182).


Using a digital input as a drive enable input (optional)

A general purpose digital input can be configured as a 'drive enable input'. This input
must be activated to allow the drive to operate. This provides an additional method for
stopping the drive using a hardware switch or external PLC/controller (e.g. AC500)
although it does not provide any of the formal safety features of the Safe Torque Off
inputs (see page 187). The optional drive enable input is configured using the Digital
I/O tool in Mint WorkBench.


Using a digital input as a home switch input (optional)

If homing is being handled locally by the MicroFlex e190, the axis home switch (if
present) must be wired directly to the home input on the MicroFlex e190, otherwise it
will not be able to complete its internal homing routines. The home switch input is
configured using the Digital I/O tool in Mint WorkBench, or by using the Mint
HOMEINPUT keyword. Other HOME... keywords define the homing sequence.
If homing is being handled by an EtherCAT
profiling the motion, there are three options. The choice depends on the accuracy
required for the homing and the EtherCAT cycle-time:
• The axis home switch is wired to an input on the MicroFlex e190, and then
mapped back to the master over EtherCAT;
• The home switch is wired directly to the EtherCAT master;
• The home switch is wired to one of the fast inputs (DI1 / DI2), and the master (or
the manager node) enables the drive's touch probe function. See the Mint
WorkBench help file for details.


X4: Digital inputs - Safe Torque Off (STO) inputs

The two safe torque off (STO) inputs are identical. Each input directly enables part of
the motor output control circuit. Both inputs must be powered to allow the
MicroFlex e190 to supply power to the motor. If an additional hardware drive enable
input is used to control the MicroFlex e190, it must not be wired with the STO input
circuit. The state of the STO inputs can be viewed using the Mint WorkBench Spy
window's Axis tab or via the Mint SAFETORQUEOFF keyword. See the Mint help file
for details.
See Appendix: Safe Torque Off (STO)
®
master over Ethernet, and the master is
on page 187.