SJ700
2
Inverter
Oper
ati
ons
and Monitor
ing
4–21
External Trip
When the terminal [EXT] transitions OFF-to-ON, the inverter enters the trip state, indicates
error code E12, and stops the output. This is a general purpose interrupt type feature, and the
meaning of the error depends on what you connect to the [EXT] terminal. Even if [EXT] is
turned OFF, the inverter remains in the trip state. You must reset the inverter or cycle power to
clear the error, returning the inverter to the Stop Mode.
In the graph below, the [EXT] input turns ON during normal Run Mode operation. The inverter
lets the motor free-run to a stop, and the alarm output turns ON immediately. When the
operator initiates a Reset command, the alarm and error are cleared. When the Reset is turned
OFF, the motor begins rotation since the Run command is already active.
If the USP (Unattended Start Protection) feature is in use, the inverter will not automatically
restart after cancelling the EXT trip event. In that case, it must receive either another Run
command (OFF-to-ON transition), a keypad Reset command, or an [RS] intelligent terminal
input signal.
Unattended Start
Protection
If the Run command is already present when power is turned ON, the inverter starts running
immediately after powerup. The Unattended Start Protection (USP) function prevents that
automatic startup. If the [USP] input is active, the inverter
will not
run without outside interven-
tion. In this case, there are two ways to reset an alarm and resume running:
1.
Turn the Run command OFF, or
2.
Perform a reset operation by the terminal [RS] input or the keypad Stop/reset key
The three examples below show how the USP function works in the scenarios described at the
bottom of the diagram. The error code E13 indicates the USP trip state and corresponds to the
Alarm
signal in the diagram.
Note the following;
• Note that when a USP error occurs and it is canceled by a reset from the [RS] terminal input
or keypad, the inverter restarts immediately.
• Even when the trip state is canceled by turning the terminal [RS] ON and OFF after an
under- voltage trip E09 occurs, the USP function will be performed.
Opt. Code
12
Symbol
[EXT]
Valid for
Inputs
[1] to [8]
Required
Settings
(none)
Default
terminal
Requires
config.
[EXT]
[FW, RV]
[RS]
Motor revolution speed
Alarm output terminal
t
free run
Opt. Code
13
Symbol
[USP]
Valid for
Inputs
[1] to [8]
Required
Settings
(none)
Default
terminal
[6]*
* Default for -FU2 models
only; others require input
configuration
Power
supply
[FW]
Output
frequency
When USP is ON after powerup, the
alarm (E13) will clear when the Run
command (FW or RV) turns OFF.
[USP]
[RS]
Alarm
If the alarm is cleared
during Run command,
the inverter output
restarts automatically.
If the Run command is
already OFF at powerup,
the inverter output starts
normally.
Example 1
Example 2
Example 3
t