Altivar® 58 TRX AC Drives
Assignment of Logic Inputs (LIx)
© 2000–2003 Schneider Electric All Rights Reserved
56 09/2003
Forced Local
This function allows a logic input to be assigned to force local control of the
drive controller. Configuration of this function is recommended when using
serial communication with the drive controller. Th is input is typic ally wired into
the Hand and Off positions of a Hand-Off-Auto selector switch when u sed in
conjunction with serial communication with the drive controller . Assigning this
parameter provides terminal block control w h en the logic input is closed
(state 1). Initiating this input overrides any commands being received over
the serial communications link and the drive controller responds to the inputs
given at the control terminal block. Parameter data can sti ll be monitored o ver
the serial communication link.
Fault Reset
This function allows faults to be reset by a logic input assigned to this
function. Two types of reset are available. See page 66 for fault reset types.
External Fault
This function allows a logic input to be assigned to receive an external
contact closure to stop the drive controller and motor. The driv e controller wi ll
stop according to the controlled stop configuration. This function is us eful in
applications where interlocking of various equipment and the drive controll er
is required.
Reference Switching (Auto – Manual)
The Reference switching function permits switching between two analog
references by logic command. This function avoids switching of low-level
speed reference signals by other means, and enables the two reference
inputs AI1 and AI2 to be independent. To use this function, one logic input
(LI) must be re-assigned.
This function is typically used for:
• Machines with automatic/manual operation such as pumps
• Automatic control via a sensor on input AI2, validated by the lo gic input a t
state 0
• Manual control via potentiometer on input AI1 (local control)
A graphical representation of reference switching and a co nnection diagram
are shown to the left.
Auto Tune
This parameter causes the drive controller to auto tune the connected motor.
When Auto Tune is initiated, the drive c ontroller p ulses the c onnected motor,
and measures and stores motor stator resistance and conductor resi stanc e.
This allows the drive to provide better current regulation for improved motor
torque performance. Auto Tune can be init iated from the k eypad or by a logic
input assigned to this function. If an output contactor is used, it is necessary
to close the contactor before the auto tune function is initiated.
f
(
Hz
)
t
t
t
F
o
rw
a
r
d
or
R
e
v
e
r
se
LIx
COM
AI1
AI2
+ 24 V
0-20 mA
4-20 mA
20-4 mA
+–
+10
1
0
1
AI2
LIx
0
R
efSwitch.e
p
s
Connection Dia
g
ram for Reference Switchin
g
Remote
Signal
Reference Switching Timing and Wiring
Diagrams