GH Start Home

syntax – GH± r

Value:

N/A

 

Units:

set in EDIT > SETUP > MECH > ACCEL > VEL

 

Range:

Unit scaling dependent

 

Initiates a homing routine (seeks the home switch) to establish a home reference position. When it reaches home, the position counter is set to zero or to the Home Offset (HO) value selected in the EDIT > SETUP > HOME menu. The motor will move at the GH velocity (n) and direction (± ) specified until it either finds a home limit switch or determines that it can not find one between the two end–of–travel limit switches. The Go Home move uses the last acceleration and deceleration specified.

The exact homing routine used, and the ultimate end position of your system’s home reference, depends on the values of your EDIT > SETUP > HOME parameters (edge, level, final approach direction, and offset) and if you have specified open or closed loop moves in the EDIT > SETUP > ENCODER menu. The control will reverse direction when the first End of Travel limit switch is encountered while searching for a Home switch. If the second End of Travel switch is encountered, the unit will abort the Go Home move and generate a fault. Assuming the presence of an operational home switch, the control will seek a home position according to the parameters you specified (edge, level, final approach direction, and offset).

Closed loop systems will normally home with more accuracy than open loop systems because encoders have a Z marker pulse. In a typical Go Home routine, the control will first sense the edge of the switch defined in the Go Home SETUP menu. It will then decelerate the motor to a stop at the last defined deceleration rate. The final homing motion is determined by the Go Home options selected in the SETUP menu. The final homing direction dictates the direction from which the final approach to the switch is made. The edge selected will determine which side of the home switch this final approach will be based from.

In a “closed loop” mode Go Home routine, the control will additionally slow to a creep speed and stop when it sees the encoder’s “Z” Marker Pulse after seeing the reference edge of the switch. If a marker pulse is not seen within one motor revolution after the reference edge of the switch is seen, the final homing routine will be aborted. Note: Homing Mode directly affects or reconfigures the function of the GH command.

Examples:

AC.5

DE.5

GH–20

Go Home in the negative direction at a speed of 20

AC.5

DE.5

GH20

Axis one Go Home in the positive direction at a speed of 20.

MN1854

Keypad Programming 6-9

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Baldor mn1854 manual GH Start Home, Set in Edit Setup Mech Accel VEL