Delta MMC120 - Manual (Page 13)

13
enter ALT+SHIFT+O, and verify that the DRIVE for the axis is 0 (zero). If the
NULL DRIVE is not zero, enter ALT+N to clear it.
NOTE: Make sure the Simulate Bit in the Config word is off. Otherwise,
Open Loop commands (ALT+SHIFT+O) will not affect output.
E.Turn on power to the motor or hydraulics for the axis being set up (the axis may
drift due to valve null errors).
F. Next, we will output 500mV to the axis drive output. Enter 500 in the
COMMAND VALUE field, enter ALT+SHIFT+O, then enter 0 (zero) in the
COMMAND VALUE field. Verify that the DRIVE for the axis is 500. The
axis should extend. If the axis retracts, check the drive wiring polarity,
hydraulic plumbing (if applicable), and valve null.
NOTE: The extend direction is defined as the direction in which the
transducer counts increase. Watch the Transducer Counts field in
DCS120-Win to see that the counts increase. On MDT axes, the
extend direction is away from the head of the MDT. The retract
direction is opposite from the extend direction.
G.Ensure that the COMMAND VALUE field is still set to 0 (zero), and enter
ALT+SHIFT+O, then ALT+P to stop the axis.
H. Next, we will output -500mV to the axis drive output. Enter -500 in the
COMMAND VALUE field, enter ALT+SHIFT+O, then enter 0 (zero) in the
COMMAND VALUE field. Verify that the DRIVE for the axis is -500. The
axis should retract. If the axis extends, check the drive wiring polarity,
hydraulic plumbing (if applicable), and valve null.
I. Ensure that the COMMAND VALUE field is still set to 0 (zero), and enter
ALT+SHIFT+O, then ALT+P to stop the axis.
J. Repeat steps C through I for each axis in use.
5. Set the SCALE and OFFSET of Each Axis
The Scale and Offset parameters are used to convert raw transducer counts to user-
definable position units. Below is shown an example MDT and the affect of the
SCALE , OFFSET , EXTEND and RETRACT LIMITS :
There are two ways to set these fields:
• Use one of the Scale/Offset Calibration utilities. This is the recommended