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10. Protection/Warning function
(1) Protection function
The protection function is an important function to protect a controller or peripheral equipments. When the
protection function operates, it is short-circuited between terminals C2-EM (There may be a case that no signal
comes out depending on setting of function J12). The reset work is necessary when stopping due to the protection
function. Please reset it after investigating the cause that made the protection function to operate and executing the
countermeasure (Refer to the next page for reset).
Protection function
Content
Display
Overcurrent/earth
protection
OC lighting
(Hardware detection
and software
detection
）
・
When the output current of 1.5 times more than the
controller current rating flows, it stops controller's
driving and protects the internal circuit and wiring
(Refer to P. 51). When detected by hardware, the
subsequent operation accepts only power off.
Overload abnormality
OL lighting
・
When the output current exceeding the current rating set
by the function flows and it cannot be improved by
decreasing the output voltage, it stops the controller's
driving to protect the load.
CPU abnormality
Er1 lighting
・
When operation time abnormality of CPU is detected, it
stops the controller's driving. When it can not be reset
by power supply OFF, it is very likely to be breakdown.
Memory abnormality
Er2 lighting
・
The controller's driving is stopped by detecting the
memory abnormality (abnormal value is found in the set
data). (Refer to
⑤
of the next page)
(2) Warning function
Warning function is a function to inform various kinds of information such as driving condition. In case ”Work
shortage”, “Overload warning” and “LIMIT LED light-up” operate, signal following to setting of function J12 is
output between C2-EM terminals. In case warning operation is released, warning display and signal are reset
automatically.
Warning function
Content
Display
Overload warning
OL blinking
In case the output current exceeding current rating value set
with function J01 flows and enters into limiting action to
decrease the output voltage, it draws attention by blinking OL.
If the limiting action is released, it is automatically reset.
Work shortage
noP blinking
In case the work shortage timer is setup, noP is displayed. It
is reset by setup of the reset timer.
Voltage shortage or
excess voltage
LV lighting
In case undervoltage or overvoltage of direct current
intermediate circuit (power supply voltage) is detected, driving
of controller is stopped and LV is displayed. In case voltage
returned to normal value, it is automatically reset. Even it
operates, warning signal is not output.