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4 Functional Description
4.3 Homing and limit switches
The connections
AnIn
Fault
3., 4., 5. In, if available
can be used as reference and limit switch inputs.
In BL motors the zero crossing of the Hall sensor signals is also available as index pulse, occurring
once per revolution. The index pulse of an external encoder can also be connected to the fault pin,
enabling the actual position to be exactly zeroed.
The AnIn and Fault connections are designed as interrupt inputs, which means that they are edge-
triggered. All other inputs are not edge-triggered, so that the signal must be at least 500 μs to be
reliably detected. The maximum reaction time to level changes at all inputs is 500 μs.
Set levels of digital inputs:
Command Function
Description
SETPLC
Set PLC inputs
Digital inputs PLC-compatible (24 V level)
SETTTL
Set TTL inputs
Digital inputs TTL-compatible (5 V level)
The signal level of the digital inputs can be set using the above commands:
PLC (Default): Low: 0…7.0 V / High: 12.5 V…U
B
TTL: Low: 0…0.5 V/High: 3.5 V…U
B
Configure fault pin as reference or limit switch input:
Command Function
Description
REFIN
Reference Input
Fault pin as reference or limit switch input
The limit switch functions for the fault pin are only accepted if REFIN is activated (setting must be
saved with SAVE or EEPSAV)!
Configure before applying a voltage
The electronics can be damaged if a voltage is applied to the fault pin while it is not configured as
the input.
Configure the fault pin as input first before applying external voltage!
The function of the inputs and the homing behaviour is set with the FAULHABER commands de-
scribed below. A previously configured homing is then started with the following FAULHABER
commands:
Command Function
Description
GOHOSEQ Go Homing Sequence
Execute FAULHABER homing sequence. A homing
sequence is executed (if programmed) irrespective of
the current mode.
GOHIX
Go Hall Index
Move BL motor to Hall zero point (Hall index) and set
actual position value to 0 (not with MCDC)
GOIX
Go Encoder Index
Move to the encoder index at the Fault pin and set
actual position value to 0 (DC motor or ext. encoder).
POHOSEQ Power-On Homing Sequence
Start homing automatically after power-on.
1: Power-On Homing Sequence is activated
0: No homing after switch-on
CAUTION!