YM:Schenck Disocont®

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The DISOCONT is a versatile family of modular weighing electronics for use with weighing and feeding systems.

1 Pre-Adjustment

1.1 Mechanical Checks

Make sure that all transportation locks are removed, all load cells are not locked anymore and every compensator has to be free of tension. It’s also important that there is no force closure at all load cells. Also take care that for the Grounding of the Loadcells only High-Flexible Groundingcables are used.

• File:Schenckdisocontcelllock1.jpg
• File:Schenckdisocontcelllock2.jpg

1.2 PROFIBUS Settings

Adjust PROFIBUS Parameter:

1.3 Download Standard Parameters

Connect to Dosing Unit and download Standard Parameter. Open Easy Serve and click on File/Transmit and select the right Parameters.

2 Archive of *.ndb-Files to view Parameter Backups

If you want to open a backup from a Dosing which was never connected to your computer EasyServe will deny to show the parameters.
To avoid this problem you can download the following file: ndb-Database from Schenck
Schenck download support

File:Ndb-Download.JPG

This Databas you unpack into C:\Program Files (x86)\Schenck\Database. After that you should be able to view all backup Parameter-files.

3 Explanation of Scale Operation Mode

Activate Scale Operation Mode: View → Scale Operation 1

Abbreviation	Explanation
Template:Image	Start / Stop Dosing Unit
Template:Image	Lock / Unlock Easy Serve User Interface
Template:Image	By entering a setpoint to P you can adjust the actual feeding rate in kg/h
Template:Image	I shows the value of the actual feeding rate in kg/h
OP Mode	Start / Stop Keyboard Mode
VSM Type: A	Switching between “Volumetric” or “Gravimetric” Mode
Deviation	Difference between Setpoint P and the actual value I in percent

4 Commissioning

Attention:
In fact we have two different types of Dosing Units. Units with a dosing screw and Units with a vibro feeder. They have to be adjusted in different ways.

4.1 Dosing Unit with a vibro feeder

• Check refill flap
  • Open Scale Operations and Unlock Easy Serve User Interface.
  • Press button “Filling Start”. Refill flap should open.
  • Press button “Filling Stop”. Refill flap should close again.
  • If the refill flap is not opening, check wiring, check pneumatic and make sure that Parameter P 15.06 “DO Gate” is “DO/VSE1/DO2/HIGH”.

• Adjustment of Parameters
  • Open the Parameter panel.
  • Set parameter P 02.05 “Nominal Feed Rate” to maximum feed rate of the Dosing Unit. For example, if the maximum feed rate of the dosing unit is 280 kg/h then write this value into parameter P 02.05.
  • Set parameter P 04.04 “load cell characteristic value” (Cn) and parameter P 04.05 “load cells rated capacities” (Emax) according to values on the load cell. For example, if there are 2 load cells connected parallel and each load cell has an Emax of 150 kg, the Parameter P 04.05 has to be set to 300 kg. If the Cn value is 2 mV/V set Parameter P 04.04 to 2mV/V.
    
    Note: These two Parameters are written on a label on the load cell.
    
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  • Parameter P 05.04 Nominal Amount Fo [%] indicates the maximum material capacity of the hopper (100% Level Max [kg]) in dependence of the load cell capacity. 100% Level Max [kg] = (P 05.04 Nominal Amount Fo [%] * P 04.05 LC Rated Cap. [kg]) / 100
    

Example:

P 05.04 Nominal Amount Fo = 20%

P 04.05 LC Rated Cap. = 3 * 500kg = 1500kg.

According to the formula, the maximum material capacity is 300kg. Check, if this is possible.

The filling sequence starts after it reached Level Min which you can adjust with Parameter P 05.09 F_CONTROLmin and its stops after it reached Level Max which is adjustable with Parameter P 05.10 F_CONTROLmax.

Start filling:
Level Min (kg) = (100% Level Max * P 05.09 F_CONTROLmin) / 100
Stop filling:
Level Max (kg) = (100% Level Max * P 05.10 F_CONTROLmax) / 100

Note:Filling level of big Dosing Units should be as high as possible to have long gravimetric time periods ( but not more then 75 % of the maximum hopper capacity). Filling level of small Dosing Units should be less high to prevent adherence of the granulate(e.g. antistatic). To check if the hopper becomes not filled up with too much or too less material start filling sequence (Scale Operation Mode / Press Button “Filling Start”)and check how much material is inside the hopper.

• • Set Parameter P 10.01 KP to 0.65.
  • Set Parameter P 10.03 Bypass to 10 mA
  • Set Parameter P 10.04 Contr. Magn. Offset to 0 mA.
  • Set Parameter P 10.06 Lower Limit to 0 mA
  • Set Parameter P 10.07 Upper Limit to 20 mA
  • Set Parameter P 11.01 Linearization to “Off”.

Note:
This calibration step has to be done without any material. Make sure that there is no material already inside the hopper, all load cells are not blocked by the Transportation locks anymore and that the load cell 
Parameters P 04.04 and P 05.04 are correct.

• Select "TW: Tare" program in Tools -> "Calibration Programs"
• Start Calibration Program “TW Tare”
• Wait until calibration is done and the new tare value is displayed, then press button apply
• Check calibration by putting a weight on 3 different points on the hopper and see if PVSS shows the right value. If not, check load cell wiring, transportation locks and start calibration again.

Attention:
For the next Calibration Steps we need material. Make sure that the Calibration Steps are done with the same material which is used to run the line. Then open Scale Operation and start the Keyboard Mode.

4.1.1 Calibration of the External Controller

• Set operation mode to “Volumetric”
• Start Dosing by pressing Button “Start”
• Set P to nominal feed rate (Value Parameter P 02.05)
• Adjust Poti R1 (See figure 4) of the External Controller until the value of the

actual feeding rate I is around the same as the set point P.

• Set P to zero
• Increase Parameter P 10.04 Contr. Magn. Offset in small steps (e.g.: start with 0.1 mA and step up with 0.05 mA) until the vibro feeder just starts moving the material a little bit. Then take 10 % off the adjusted value and write the new value into Parameter P 10.04.

Note: To see if the material is moving a little bit you may open the yellow cap of the vibro feeder.

• Set again set point P to nominal feed rate and adjust Poti R1, according to point d).
• Stop Dosing by pressing Button “Stop”

Attention:
For the next steps always wait until the filling sequence is done before you start a Calibration Program. To start a Calibration Program open Tools/Calibration.

4.1.2 Calibration of Vol. Discharge Adaption, Optimization Controller and DAE Adjustment

• Open Scale Operations
• Set operation mode to “Gravimetric”
• Start Dosing by pressing Button “Start”
• Set P to the nominal feed rate
• Start Calibration Program “Vol. Discharge Adaption”
• Wait until Deviation is around zero and for control magnitude and set/act value to stabilize on display.
• Press Button “Apply”. Value should be taken over into Parameter P 10.03 Bypass
• Start Calibration Program “Optim. Controller"
• Wait until Deviation is around zero and for P-Component KP and I-Component TN to be displayed
• Press Button “Apply”
• Start Calibration Program “DAE Adjustment“
• Wait until Deviation is around zero and maximum disturbance and standard deviation to be displayed
• Press Button “Apply”

Note: To make sure everything is working well you should repeat the calibration programs “Vol. Discharge Adaption” and “DAE Adjustment” after Start Up again.

4.1.3 Linearization of P1-P4

Note: The vibro feeder discharge characteristic is non-linear. To improve the assignment of set points to actual values and the control quality in gravimetric mode, linearization has to be performed.

• Enter feed rate to P in percent of the nominal feed rate (Parameter P 02.05).

Note: Useful values are, for instance, P1 = 5%, P2 = 25%, P3 = 50%, P4 = 90% of the nominal feeding rate

For example:

If the nominal feeding rate of the Dosing Unit is 280 kg/h
we going to set  P1 = 14 kg/h, P2 =70 kg/h, P3 = 140 kg/h, P4 = 252 kg/h

We start with the calibration of P1 so the nominal feeding rate has to be set to P= 14 kg/h

• Open Calibration Programs
• Start Program Linearization P1
• Wait until deviation value is around zero
• Acquire result by pressing apply
• Call up Linearization Program P2 and repeat steps a) to e) (Don’t forget to change P to P2)
• Call up Linearization Program P3 and repeat steps a) to e) (Don’t forget to change P to P3)
• Call up Linearization Program P4 and repeat steps a) to e) (Don’t forget to change P to P4)
• Set Parameter P 11.01 Linearization to “On”
• Set all set points from P1 to P4 again and check if actual feeding rate I reaches the Setpoint P more smoothly.

Note: To make sure that Linearization was done correct, check Parameters 11. The values should increase from Y1/I1 to Y4/I4.

4.1.4 Function Test

For the function test start Dosing Unit over PVSS and set different set points for the feeding rate. Open Scale Operations and check if the actual value of the feeding rate I controls the different set points. If it takes to long until the actual value I reaches the set point P you can adjust it by changing Parameter P 10.01 (P-Component KP of controller). Furthermore, check if refilling is working correctly.

4.2 Dosing Unit with a Dosing Screw

4.2.1 Check refill flap and cleaning unit

• Open Scale Operations
• Press button “Filling Start”. Refill flap should open and cleaning should start
• Press button “Filling Stop”. Refill flap should close again
• If the refill flap is not opening or cleaning doesn’t start, check wiring, check pneumatic and make sure that Parameter P 15.06 “DO Gate” is “DO/VSE1/DO2/HIGH”.

4.2.2 Parameter Adjustment

• Set Parameter P 02.05 Nominal Feed Rate to maximum feed rate of the Dosing Unit. For example, if the maximum feed rate of the dosing unit is 4600 kg/h then write this value into P 02.05.
• Set Parameter P 04.04 Load Cell (LC) Characteristic Value (Cn) and P 04.05 LC Rated Capacities (Emax) according to values on the load cell. For example, if there are 3 load cells connected parallel and each load cells has an Emax of 2200 kg then the Parameter P04.05 has to be set to 6600 kg.

Note: These two Parameters are written on the load cells.

• Parameter P 05.04 Nominal Amount Fo indicates the maximum material capacity of the hopper (100% Level Max (kg)). 100% Level Max (kg) = (P 05.04 Nominal Amount Fo * P 04.05 LC Rated Cap.) / 100

The filling sequence starts after it reached Level Min which you can adjust with Parameter P 05.09 F_CONTROLmin and it stops after it reached Level Max which is adjustable with Parameter P 05.10 F_CONTROLmax.

Start filling:
Level Min (kg) = (100% Level Max * P 05.09 F_CONTROLmin) / 100
Stop filling:
Level Max (kg) = (100% Level Max * P 05.10 F_CONTROLmax) / 100

 Note:
 Filling level of big Dosing Units should be as high as possible to have long gravimetric time periods ( but not more then 75 % of the maximum hopper capacity). Filling level of small Dosing Units should be less high
 to prevent adherence of the granulate (e.g. antistatic). To check if the hopper becomes not filled up with too much or too less material start filling sequence(Scale Operation Mode / Press Button “Filling Start”) 
 and check how much material is inside the hopper.

• Set Parameter P 10.01 KP to 0.65.
• Set Parameter P 10.03 Bypass to 8.2 mA
• Set Parameter P 10.04 Contr. Magn. Offset to 4 mA
• Set Parameter P 10.06 Lower Limit to 4 mA
• Set Parameter P 10.07 Upper Limit to 20 mA
• Set Parameter P 11.01 Linearization to “off”.

4.2.3 Hopper calibration

Note:
This calibration step has to be done without any material. Make sure that there is no material already inside the hopper, all load cells are not blocked by the Transportation locks anymore.

• Select "TW: Tare" program in Tools -> "Calibration Programs"
• Start Calibration Program “TW Tare”
• Wait until calibration is done and the new tare value is displayed, then press button apply
• Check calibration by putting a weight on 3 different points on the hopper and see if PVSS shows the right value. If not, check load cell wiring, transportation locks and start calibration again.

Attention:
For the next Calibration Steps open Scale Operation and start the Keyboard Mode. Always wait until the filling sequence is done before you start the Calibration Program.

4.2.4 Calibration of Vol. Discharge Adaption, Optimization Controller and DAE Adjustment

• Open Scale Operations and start the Keyboard Mode
• Set operation mode to “Gravimetric”
• Start Dosing by pressing Button “Start”
• Set P to the nominal feed rate
• Start Calibration Program “Vol. Discharge Adaption”
• Wait until Deviation is around zero and for control magnitude and set/act value to stabilize on display.
• Press Button “Apply”. Value should be taken over into Parameter P 10.03 Bypass
• Start Calibration Program “Optim. Controller"
• Wait until Deviation is around zero and for P-Component KP and I-Component TN to be displayed
• Press Button “Apply”
• Start Calibration Program “DAE Adjustment“
• Wait until Deviation is around zero and maximum disturbance and standard deviation to be displayed
• Press Button “Apply”

Note: To make sure everything is working well you should repeat the calibration programs “Vol. Discharge Adaption” and “DAE Adjustment” after Start Up again.

4.2.5 Function Test

For the function test start Dosing Unit over PVSS and set different set points for the feeding rate. Open Scale Operations and check if the actual value of the feeding rate I controls the different set points. If it takes to long until the actual value I reaches the set point P you can adjust it by changing Parameter P 10.01 (P-Component KP of controller). Furthermore, check if refilling is working correctly.

5 Final Function Test

Start all Dosing Units and set different set points for the feeding rate. Check if everything is working correctly. At the end don’t forget to save the parameter: File/SaveAs…

6 Unexpected Consumption Reset

If you observe a unwanted reset of a dosing unit's actual consumption, you need to check P2.09.

Make sure that it is tons [t] with one digit after the decimal point.

Definition