3. The discharge valve is not functioning (closing) normally.
If material is clogging and the valve is not completely closed, an air leak will cause the vacuum alarm to start.
Check the condition of the valve. Especially during use of mixed materials of granulating materials, check to see if particles or spool runner parts are caught or not.
[Point] Use extra caution to avoid scratching the seal of the valve. [Point] If the spool runner parts are long, break part down twice.
If material is caught, clean the valve. Also, if material is clogging the valve, adjust the secondary convey blow time and the secondary convey air. If the valve (solenoid valve) is damaged, repair or replace.
7. Vacuum pressure switch is not working properly.
If the switch, which checks the vacuum pressure, is not functioning normally, the vacuum alarm will light up even if the pressure is within the specified range.
Check to see if the switch is functioning at -0.04 MPa. Also, remove the pressure switch to see if any powder or oil from the gas has penetrated the sensor.
(References) The specified pressures are as follows:
0MPa ~ -0.046MPa (maintenance zone)
-0.046MPa ~ -0.07MPa (caution zone)
-0.07MPa ~ 0.096MPa (normal zone)
In certain cases, please remove the switch to have it repaired or replaced.