9.3.7 Protective operation
Minor failure and serious failure
There are two levels in the failure of the SX bus option: minor and serious.
Upon occurrence of a failure, the converter issues Er4 "Network Error."
Item
Minor failure
Serious failure 1
Serious failure 2
Cause
• Communication data error
caused by noise intruding
into communication cable
• All masters shutdown
• Detection of broken wire
• SX bus power shutdown
• Failure of option hardware
• Improperly installed option
Resetting method
Remove the cause of the alarm (restore communication to
automatically remove) and give a reset command (keypad panel,
[RST] or resetting through communication).
After removing the cause of
the alarm, turn the converter
off then on again.
Control of failure
status
Alarm detection is performed
only while operation
commands are given through
the SX bus.
The alarm can be controlled,
using function codes H02 and
H03.
Er4 alarm is caused immediately upon a serious failure.
Communication
error code
displayed at
keypad panel
1
2
3
Note:
In serious failure category 1, the CPU must be reset, too, according to some states of the CPU of the
MICREX-SX.
The communication error code in a minor or serious failure can be checked on the communication state screen in
maintenance data at the keypad panel. To reach the communication state screen, press the
PRG
key on the operation
mode screen to call up the menu screen, use the
∧
or
∨
key to move the arrow on the left end of the screen to "5.
Maintenance," and press the
FUNC/DATA
key. Next, press the
∨
key three times to display the screen shown
below.
NRK =xxxxx
NRR =xxxxx xx
NRO =xxxxx xx
NRL =xxxxx xx
０
-: No error
1: Minor failure
2: Serious failure 1
3: Serious failure 2
9-23
