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4 Functional Description
4.3 Homing and limit switches
Configuration of homing and limit switches:
The following commands use the following bit mask for configuration of the limit switch functions:
7
6
5
4
3
2
1
0
Analog input
Fault-Pin
3rd input
4th input
(only MCDC)
5th input
(only MCDC)
Set or delete the bit at the position of
the required input for each command
and assign the resulting numeric value
to the commands described below.
Polarity and limit switch function:
Command Function
Description
HP
Hard Polarity
Define valid edge and polarity of respective limit
switches:
1: Rising edge and high level effective.
0: Falling edge and low level effective.
HB
Hard Blocking
Activate Hard Blocking function for relevant limit
switch.
HD
Hard Direction
Presetting of direction of rotation that is blocked
with HB of respective limit switch.
1: Clockwise rotation blocked
0: Anticlockwise rotation blocked
The Hard-Blocking function provides reliable protection against overshooting of the range limit
switch. If the drive is located in an HB limit switch, then the direction of rotation set with HD will be
blocked, i.e. the drive can only move further out of the limit switch.
The speed stays at 0 rpm if target velocities are preset in the wrong direction.
Example:
Setting of the Hard-Blocking function for Fault pin and 4th input: 2
1
+2
3
= 2+8 = 10
HB10
Definition of homing behaviour:
Command Function
Description
SHA
Set Home Arming for Homing Sequence
Homing behaviour (GOHOSEQ): Set position value to
0 at edge of respective limit switch.
SHL
Set Hard Limit for Homing Sequence
Homing behaviour (GOHOSEQ): Stop motor at edge
of respective limit switch.
SHN
Set Hard Notify for Homing Sequence
Homing behaviour (GOHOSEQ): Send a character to
RS232 at edge of respective limit switch.
In order to be able to execute a homing sequence with the command GOHOSEQ, a homing sequence
must be defined for a specific limit switch!
If the drive is already located in the limit switch when GOHOSEQ is invoked, first of all it moves out
of the switch, in the opposite direction to that specified for HOSP.
