IAI America ERC2 User Manual
Page 105
5. Data Entry
82
Full servo control mode
The pulse motor is servo-controlled to reduce the holding current.
Although the exact degree of current reduction varies depending on the actuator model, load condition, etc., the
holding current decreases to approx. one-half to one-fourth.
Since the servo remains on, no position deviation occurs.
The actual holding current can be checked in the current monitor screen of the PC software.
Take note that micro-vibration or noise may occur in certain conditions where external force is applied, or depending
on the position where the actuator has stopped.
If micro-vibration or noise presents problem, do not use this mode.
Automatic servo-off mode
After positioning is completed, the servo will turn off upon elapse of a specified time.
(Since no holding current flows, the power consumption decreases.)
When the PLC issues the next movement command, the servo will turn on and the actuator will start moving.
* Since the servo turns off once, some position deviation may occur.
Do not use this function at standby positions where position deviation will cause problem.
You should also note that all position complete signals (PEND, PE0, PE1, PE2) will turn OFF because the servo turns
off.
However, you can keep the signals ON via a parameter in situations where the PLC sequence circuit is designed in
such a way that problems will occur if position complete signals turn OFF.
Setting of parameter No. 39
(Output mode of position
complete signal)
[1] PIO pattern = 1 (3 points)
Rear end complete (PE0), front end complete (PE1), or intermediate point
complete (PE2)
[2] PIO pattern = 0, 2, 3 (8 points/16 points)
Position complete (PEND)
0 [PEND]
The position complete signal is OFF unconditionally when the servo is off.
Even when the next movement command is issued and the servo turns on again,
the actuator has already started moving to the next target position, so the position
complete signal still remains OFF.
1 [INP]
Even when the servo is off, the position complete signal turns ON if the current
position is within the range set by the “Positioning band” field of the position table,
with respect to the target position, and turns OFF if the current position is outside
this range.
(Note) The factory setting is “0.”