7.1.4 Start jog mode (on positioning opmode)
Jog mode is started in a similar manner to homing. To start, Bit 8 STW must be set. The jog velo-
city is given by the product of the 16-bit main setpoint in PZD2 and the multiplier defined by PNU
1894. The sign of the main setpoint determines the direction of movement.
It is not necessary to have a reference point set for jogging.
7.1.5 Set reference point
Take care that the position of the reference point permits the following positioning operations.
The parameterized software limit-switches in the servo amplifier may not be effective. The axis
could then drive up to the hardware limit-switch or the mechanical stop. There is a danger of
damage being caused.
The control word (STW) Bit 12 = 1 defines the present position as being the reference point. The
positioning functions are enabled. The shifting of the zero point (NI-offset) is ineffective.
The replay “Reference point set” is made through Bit 17 in the manufacturer-specific status
register (PNU 1002) or Bit 1 (manufacturer status of the process data).
Condition:
PNU930 ≠ -16
No motion function active manufacturer specific status, process data 5 bit 0.
7.1.6 Start homing run
After switching on the 24V auxiliary voltage the system must first of all carry out a homing run.
Take care that the position of the machine zero point (reference point) permits the following pos-
itioning operations. The parameterized software limit-switches in the servo amplifier may not be
effective. The axis could then drive up to the hardware limit-switch or the mechanical stop.
There is a danger of damage being caused.
If the reference point (machine zero point) is approached too fast, with high moments of inertia
in the system, then it might be overrun, and the axis could then drive up to the hardware limit-
switch or the mechanical stop. There is a danger of damage being caused.
The homing run is started by the control word (STW) Bit 11 = 1. The start of the homing run is
detected by a positive transition edge for Bit 11.
If Bit 11 is set to 0 again, before the reference point has been reached, then the homing run is can-
celed. Status word (ZSW) Bit 17 remains at 0 (reference point not set).
A set reference point is a precondition for all the positioning functions of the linear axis. The ref-
erence point switch is wired up to a digital input on the servo amplifier.
Depending on the type of homing run, you can freely shift the zero crossing point of the motor
shaft within one turn, by using the parameter “Zero-point offset” (NI-offset). Furthermore, you can
fix the position value to be the reference point by using the reference offset.
After the homing run, the amplifier signals “InPosition”, thereby enabling the position controller.
The velocity for the homing run is transmitted with the setpoint HSW (PZD 2), as a 16-bit value.
Multiplying this by the value of PNU 1894 determines the 32-bit speed. The sign is not evaluated.
Conditions :
State of the state machine = “Operation enabled” No warning message (ZSW Bit 7 = 0)
The following diagram uses the homing run Type 1 (negative direction of motion, positive rotation,
starting point in negative direction relative to the reference switch) as an example to illustrate the
signal sequence of the relevant bits in the manufacturer-specific state.
S300-S400-S600-S700 PROFIBUS | 7 Appendix
Kollmorgen | kdn.kollmorgen.com | December 2019 47