Mitsubishi Electronics MR-MC240 Sleep Apnea Machine User Manual


 
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9. INTERFACE MODE
9.10.2 Absolute position system
When using servo amplifiers with absolute position system setting, the absolute position restored when
connected to SSCNET is a position calculated from the "home position coordinates", "home position within 1
revolution", and "home position multiple revolution data" set to the parameters. Afterwards, a coordinate
system value for when the SSCNET is connected needs to be used for the position command that the user
program applies to position board until connecting to SSCNET again.
Similar to an incremental system, the coordinate system does not change after home position return operation
(after home position set). As a result, the actual home position of the machine and the home position of the
position command (position when SSCNET is connected) is different, therefore, the position command is
calculated using the machinery command position and home position offset with the following formula.
Position command = Machinery command position + Home position offset
(1) When connected to SSCNET (home position is not determined)
Because the current command position (position command) when SSCNET connection is restored is 0, set
home position offset to 0.
Until home position is determined, machinery command position is undefined. Use the position that is
referred to when connected to SSCNET (=0) as the machinery command position.
Absolute position restored by servo amplifier (=0)
Current command position
Position command (=machinery command position)
Home position offset
(
=0
)
(2) Home position return
Move to home position on the user program side, execute home position set, and determine the home
position. The home position of the position command (distance from position when connected to SSCNET
to home position) is the home position offset after home position return.
Position command
Machinery command position (=0)
Current command position
Home position
Home position offset
Absolute position restored
by servo amplifier (=0)