1 Example of Pressure Switch PSE561:[edit | edit source]
File:SuctionUnits Pressure Sensor.JPG
If you have an analog pressure sensor where the alarm minimum hast to be set do as follow for the individual systems. You can find these values also in SAP by entering the material number of the suction unit
| Suction Unit Type | Suction power | Alarm Minimum value |
|---|---|---|
| F42 | 1,1 kW | -150 mbar |
| F44 | 2,2 kW | -215 mbar |
| F48 | 4 kW | -270 mbar |
| F44/2 | 4 kW | -390 mbar |
| F48/2 | 5,5 kW | -450 mbar |
| F416/2 | 11 kW | -450 mbar |
2 Additional Help & Troubleshooting[edit | edit source]
In addition to the function description above, here is a trend of a running suction unit, to show one whole working cycle of the unit in a simplified version, as well as some troubleshooting options:
2.1 Step 1 : Beginning of Cycle Time:[edit | edit source]
As can be seen here, the moment the suction unit starts its working cycle, the flap shuts close because of the vacuum inside the unit. This means the “Flap Close Input” is on, while the “Flap Open Input” goes off. The start of the working cycle is shown by the blue arrow in the diagram below.
2.2 Step 2 : Suction Time[edit | edit source]
In the adjusted Suction Time (Parameter Panel), which is shown by the blue arrow below, the Suction Unit should now convey enough material to trigger the Level Maximum Sensor. Level Maximum is shown by the green arrow below.
If the Level Maximum Sensor isn´t triggered in this time, consider adjusting the conveying time according to your specific circumstances, for example the pipe length, the general setup-situation (maybe the material reception is on the ground floor, but your suction unit is e.g., 10m higher, very far away etc.)
Also sometimes adjusting the Pipe Cleaning Time is very helpful, because if this is set too low, the material can get stuck inside the pipe, and the suction unit might not be able to get it out in time, causing material faults.
2.3 Step 3 : Level Maximum reached / End of Conveying circle[edit | edit source]
As soon as the Level Maximum Sensor was triggered, the emptying valve opens, so that air is sucked through the suction pipe, to clear it of any material left. After this step, the conveying valve switches to bypass position, releasing the vacuum on the flap. This means the flap opens, releasing the material into the hopper beneath it. After this has happened – and after the preadjusted Off Delay Time – a new conveying circle can start. The Off Delay Time is shown by the black arrow here.
2.4 Parameters / Settings to consider while commissioning / troubleshooting[edit | edit source]
1.) Manual Valves on material reception stations:
In some cases, you will find manual valves underneath your material reception station. These are for adjusting the air flow besides the material! This means, they should never be shut completely or blocked because of dust / dirt or some other cause. If this is the case, the suction unit won´t be able to convey enough material in the required time. If in doubt, also ask your Process Engineer on site, but you can start testing with the valve a bit more than half open, and if needed, try different adjustments later.
2.) Check the pressure of your unit!
If you can´t reach your required amount of material in the adjusted time, check the value of the pressure sensor (blue arrow) and compare it with the table above. If it differs to much from these values, you might have a problem with material stuck inside your feeding pipes, a blocked valve or filter, pipe leakage etc. Check in the Parameter Panel if the corresponding values are reasonable and readjust them if needed.
Below you find a brief explanation of the Parameters and what they´re for…
