28
Unattended Start Protection
If the Run command is already set when power is turned ON, the inverter starts running
immediately after powerup. The Unattended Start Protection (USP) function prevents that
automatic startup, so that the inverter
will not
run without outside intervention. When USP
is active and you need to reset an alarm and resume running, either turn the Run
command OFF, or perform a reset operation by the terminal [RS] input or the keypad
Stop/reset key.
In the figure below, the [USP] feature is enabled. When the inverter power turns ON, the
motor does not start, even though the Run command is already active. Instead, it enters
the USP trip state, and displays
E
13
error code. This requires outside intervention to reset
the alarm by turning OFF the Run command per this example (or applying a reset). Then
the Run command can turn ON again and start the inverter output.
Option
Code
Terminal
Symbol
Function Name
State
Description
ON
On powerup, the inverter will not resume a Run
command (mostly used in the US)
13
USP Unattended
Start
Protection
OFF
On powerup, the inverter will resume a Run
command that was active before power loss
Valid for inputs:
C001
~
C007
Required settings
(none)
Notes:
•
Note that when a USP error occurs and it is
canceled by a reset from a [RS] terminal input, the
inverter restarts running immediately.
•
Even when the trip state is canceled by turning
the terminal [RS] ON and OFF after an under
voltage protection
E09
occurs, the USP function
will be performed.
•
When the running command is active
immediately after the power is turned ON, a USP
error will occur. When this function is used, wait
for at least three (3) seconds after the powerup to
generate a Run command.
Example (default input configuration shown see
page 59
):
See I/O specs on
page 16,17.
Inverter output frequency
0
t
Inverter power supply 1
0
Alarm output terminal 1
0
[USP] terminal 1
0
Run command [FW,RV] 1
0
Events:
E13
Alarm
cleared
Run
command
USP
7
6
5
4
3
2
1
L
PCS
P24
PLC
