20
Operational functions
Protective functions
■ Interlock function (see page 32 & 47)
Interlock function works in the same way as the STOP function but uses a preference circuit. Use this function
for emergency stop.
■ Diaphragm rupture detection (see page 45)
The pump stops right after a built-in sensor detects a leak in the compartment at the back of the diaphragm.
In this condition, the operation LED lights in red colour. Replace a broken diaphragm as necessary. See page
63 for diaphragm replacement. To release this error condition, push the start/stop key (or the ESC key under
Profibus control.).
NOTE
This capacitance sensor does not work properly if liquid conductivity is 1mS/m or below. Before sending pure
water, oil or any other low-conductivity liquid, check the conductivity to see if it meets the minimum level. If it
is not satisfied, replace the diaphragm immediately when a leak is found from the drain port. Otherwise, the
pump may fail.
■ Pressure overload/Failed rotation control detection
The pump stops when a built-in pressure sensor detects 1.3-2.0 times higher discharge pressure than the
maximum level or when the hole IC which monitors the motor rotation has failed. In either condition, the opera
-
tion LED flashes in red colour. The pump resumes operation 30 seconds after the stoppage due to the pres
-
sure overload. If the overload has recurred 5 times consecutively, the pump will not resume operation any more
and will keep still. Push the start/stop key to release these error conditions.
NOTE
The activation of this function means the discharge pressure has risen 1.3-2.0 times higher than the maxi
-
mum allowable level of the pump. Set up a relief valve to protect the related devices on the discharge line
from the possible pressure rise as necessary.
OFF
ON
1
2
3
4
5times
30sec
30sec
30sec
30sec
Overload detection
Pump operation
Run
Stop
Run
Stop
Leak detection
Pump operation
A leak is detected.
OFF
ON
