Applied Motion RS-232 - Manual (Page 68)

68 920-0002 Rev. I
2/2013
Host Command Reference
EF - Encoder Function
Compatibility: Stepper drives with encoder feedback
Affects:
Stall Detection and Stall Prevention
See also: CC, CI, ER, PF commands
NOTE: The behavior of this function was updated subsequent to firmware rev 1.04L (STM17, 23). Most notably, a
power-cycle was requried to initialize the drive with a new EF setting. Drives with more recent firmware perform a
current probe and encoder alignment immediately following execution of the EF command, and do not require the
drive to be reset. All descriptions shown here assume that the drive is running current firmware.
ST-Q/Si, STM
Sets or requests the decimal equivalent of the encoder function’s 3-bit word. The encoder function can be set
through Configurator or by using the EF command. Only stepper drives with encoder inputs (optional on ST-Q/
Si, STAC5 and STM drives) running a step motor with a shaft-mounted encoder can utilize the Stall Detection and
Stall Prevention functions. Note, this feature is NOT available on the STAC6.
AMP recommends an encoder with differential outputs and a resolution of at least 1000 lines (4000 counts/rev).
EF0: Disable Encoder Functionality
EF1: Turn Stall Detection ON.
EF2: Turn Stall Prevention ON.
EF6: Turn Stall Prevention with time-out ON.
The drive performs a full current probe for encoder alignment during power-up and after each EF command is
sent. It is very important to raise the idle and continuous current settings to the maximum value and then execute
the new EF setting after a 1 second delay. Once the EF command is completed, the current may be reset to its
normal value.
Command Details:
Structure EF{Parameter #1}
Type BUFFERED
Usage READ/WRITE
Non-Volatile YES
Register Access None
Parameter Details:
Parameter #1 Encoder function setting
- units decimal equivalent of 3-bit binary word
- range 0 = Encoder function off
1 = Stall Detection
2 = Stall Prevention
6 = Stall Prevention with time-out