Operating instructions

34 Application manual Positioning 04/08

Note:

Before a positioning operation can be started, the point of reference of

the positioning operation must be determined in a homing operation.

Otherwise, error message "F1570 – No Homing Done" will be displayed

if you try to start a positioning operation.

4.2 Homing

When the drive is started, a defined starting position must be specified. In a homing

operation, the point of reference of the positioning operation is determined. All posi-

tioning data relates to this point of reference. Once the homing operation is started,

the drive moves until it reaches a home switch or limit switch and stops there. The

limit switches limit the motion path. The direction of movement (search direction) at

the start of the homing operation is defined by the homing mode. Additional the

reaching of a limit switch will change the direction of the drive (dependent on the

homing mode). The limit switches can also be used as the point of reference. For a

list of homing modes, refer to chapter "List of Homing Modes".

Homing can be started:

− via a digital input

− by a control word via system bus or field bus

− automatically before the start of a motion block positioning operation

Extension module with system bus or field bus interface required

4.2.1 Automatic of manual start of homing

Use parameter Start Homing (manual) 1235 to start homing manually via a logic

signal, e.g. via a digital input. The signal must be present until completion of the

homing operation is signaled by logic signal "59 – Homing Done". If the start signal

is reset during a homing operation, the drive will be stopped. Homing is not com-

pleted and positioning is not possible.

The homing start condition is defined by parameter Operation Mode 1220.

Operation mode

1220

Function

1 - manual

Start of homing via parameter

Start Homing (manual) 1235.

For manual start of homing, the parameter must be assigned

a logic signal or a digital input.

2 - automatic

Factory setting. Automatic start of homing if controller is

released and signal is present on

Start Positioning 1222.

Automatic homing is performed only if the drive has not been

referenced yet.

Controller release via digital inputs S1IND (STOA) and S7IND

(STOB).

Application manual Positioning 04/0834