GE FGB-M05 User Manual

MANUAL

GraviMaster-FGB-M05 (S)

Gravimetric Blender

Serial No. ...................

ISO 08.01.02.064.GB

986731

Rev. May 2001

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1.0 INTRODUCTION

2.0 CONTROLS

2.1 Blender startup

2.2 Blender status

2.3 Machine-mode

2.4 Production-modes

2.5 Mixer-mode

2.6 Dispense modes

2.7 Batch handling

2.7.1 Production control

2.7.2 Recipe to weight calculation

2.7.2.1 Method Standard

2.7.2.2 Method Percentage

2.7.3 Adding extra materials

2.7.4 Additive to regrind

2.7.5 Regrind control

2.7.5.1 Empty regrind Control

2.7.5.2 Stock Silo Control

2.7.6 Dispensing

2.7.7 Calculations

2.8 Datalogging

2.9 Certifi cates

3.0 USER INTERFACE

3.1 Operator-interface

3.1.1 Keyboard

3.1.2 User control

3.2 Recipes

3.2.1 Change components

3.2.2 Add/change recipes

3.2.3 Change current recipe

3.3 Timely information

3.3.1 Production screen

3.3.2 Material usage screen

3.3.3 Input & Output monitor

3.4 Adjustment of the gravimetric blender

3.4.1 Calibration of the weighbin

3.4.2 Tare of the weighbin

3.4.3 Hardware-reactiontime

3.5 Overview of parameters

3.5.1 Public parameters

3.5.2 Protected parameters

3.6 Reports and overviews

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3.7 Settings of the user-interface

3.7.1 Change the rights of an operator

3.7.2 Change entrycode

3.7.3 Change date and time

3.7.4 Revision code of the system

3.8 Menu hierarchy

4.0 INSTALLATION

4.1 Demanded connections

4.2 Attaching

5.0 ALARMS

5.1 Alarm reports and solutions

6.0 MAINTENANCE AND REPAIR

6.1 Maintenance

6.2 Replacement of parts

6.2.1 Replacement of printed circuit

6.3 Cleaning the machine

6.4 Transportation of the GraviMaster

7.0 TECHNICAL INFORMATION

7.1 General machine specifi cations

7.1.1 Safety measures

7.2 User-interface specifi cations

7.3 Valves specifi cations

7.4 Air pressure cylinders specifi cations

7.5 Electrical diagrams

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1.0 INTRODUCTION

GRAVIMETRIC FEEDING

An effi cient materials blending system is an essential feature of the modern plastics
processing industry. Dosing each component on the basis of weight shows distinct
advanta ges over traditional volumetric systems. The quantity of material delivered is
precise and unaffected by variations in bulk density, fl ow characteristics and particle size.

Ferlin Plastics Automation now have a range of more than twenty blenders that deliver
the benefi ts of gravimetric blending at a price that makes other gravimetric ... and most
volumetric systems ... look distinctly expensive.

FGB SERIES GRAVIMETRIC BLENDERS

“GraviMaster” blending systems are available in more than twenty diffe rent models with a
throughput capacity range from 10 to 750 kg/hr for the standard units. The number of
components on the standard unit is two to six. But purpose-built units may designed for
additional feeds up to a maximum of ten and a throughput capacity up to 1500 kg/hr.
The blending units may either fl ow-control-valve design or have a combination with
auger-feeders. The proven “GraviMaster” blending systems are being used successfully in
Injection-moulding, Blow-moulding, Sheet-extrusion and Film-extrusi on.

ACCURATE WEIGH SYSTEM

Each component is dispensed into a weigh-pan using one set of load cells. When all the
components are correctly weighed, the blend is discharged into a mixing chamber. A high
effi ciency horizontal mixer is programmed to give a uniform blend which discharges to a
storage bin with suction device, or directly into the processing machine hopper.

The system is capable of extremely accurate measurements of additive, even at very small
percentages or ratios. Load cells of the highest accuracy are used, weighing to within

0.01 gm. The accuracy of the process is enhanced by the software system which is
designed to compensate in a subsequent batch for any errors arising in a prece ding batch.
Overall accuracy of 0.1% can be achieved.

COMPACT AND MODULAR CONSTRUCTION

The units are designed and built as a modular construction using standard components
where possible, so that all components are readily obtainable. All components which
are in contact with the raw material are made in stainless steel. This includes hoppers,
valves, augers, weigh pan, mixer and mixing chamber. When auger feeders are instal led,
these can be quickly accessed for easy cleaning. The mixing chamber and weigh pan can
be removed easily for cleaning and access. The construction is in accordance with the
essential require ments under the CE regulations.

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RELIABLE PROCESS CONTROL

The FGB control system incorporates the latest in computer and micro processor
technology for total automation of recipe entry and stora ge, inventory control and process
monitoring. The control panel (user-interface) is provi ded with a micro-controller and
industrial PC with LCD-display, functional keyboard, fi ber optic communication cable (or
RS-422) and parallel printer port.

Features are:

• data storage of all plant raw materials.

• easy call up of materials for the formulation of recipes.

• fast identifi cation of recipes and call up for machine operation.

• automatic regrind control within chosen limits, so that regrind generation is matched

with usage.

• automatic additive to regrind control.

• a fi xed weight of blended material can be produced according to any of the stored

formulations.

• screen display of all process operation.

• reports of material used and batch histories can be printed on an optional printer

regularly.

• storage facility for components and recipes.

• functions are menu driven and take the operator through the required sequence of

actions with simple instructions.

• the software is pre-programmed with many options for the future, these are blenders
you won’t outgrow.

Options are:

• automatic stock silo control.

• extra level control of the blender hoppers.

• extra level control of the machine hopper.

• control and data for materials management systems.

• different language on the display.

• automatic loading of the hoppers can be provided separately with Ferlin loaders or

others of your choice.

• several blenders may be linked to a central user-interface to give integrated inventory
control over the whole process.

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2.0 CONTROLS

When all components are available the dispense of a batch starts. The cycle begins with
closing the weigh-pan. Then each of the requested components is dispensed and weighed in
the weigh-pan. When all the components of the recipe are correctly weighed, the blend is
dischar ged into the mixing-chamber. A horizontal mixer mixes the compo nents to a
uniform blend which discharges to a storage bin, or direct ly into the machine hopper.

2.1 Blender start-up

In this section is a short description of the normal start-up action of the blending system.
More details of the controls are described in the following sections. An emergency stop

can be made to shut-down the machine by pushing the button as indicated in drawing
1 in § 7.7.1.

Steps to follow for the start-up of the blending system:

[1] Plug the communication cable into the user-interface and control box on the blender.
[2] Connect air pressure to the blender and turn it on, 6 bar is recommended.
[3] Turn on the power. On the user-interface and control-box.
[4] Select the right language. The selected language is indicated.
Select a different language through key <↑> or <↓> and press <ENTER>.
[5] If necessary adjust date and time.
[6] Select the blender to be started.
[7] Select on the interface the desired recipe from the menu (F1)

‘controller / select recipe’

[8] Be sure there is no alarm active.
[9] Start the blender, press <START>.

The blender will now operate automatically on the select recipe.

2.2 Blender status

The control of the blender is based on a number of status. Each status gives an exact
description in which situation the controller is. The controller knows the following status:

Inactive

At the start-up of the blender several internal tests will be done automatically if the controller
can’t fi nd a recipe. In this status the blender will not start until a recipe is edited.

Standby

The blender is complete in rest but can be started any moment by giving the start-command.
In this status recipes, parameters and debug-commands can be sent to the controller.

Operating

The blender will now produce a blend for the selected recipe.

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Pause

When the pause-command is given for a temporary stop the blender will stop after the
cycle is complete.

Stop requested

The blender is operating but has received a stop-command. The stop-command will be
executed at the end of a batch-cycle. This status will be replaced automatically with ‘standby’
if nothing is done. If a start-command is given during the status ‘stop requested’ the status
will be ‘operate’ again.

Error
The controller has detected an error and therefore the system will stop. In a sub-menu at
the operator-interface the error will be displayed. The error situation can be recovered using
the <ENTER> command. The error must be solved then.

2.3 Machine-mode

The controller can be in two modes: Automatic and Manual. The operator can change the
mode using the menu item ‘controller’. This changing of mode is only possible while the
blender has status ‘standby’.

If a controller is in Automatic-mode, the recipe will be executed without the need of
an operator. This mode is used for production purposes and is only dependent on the
settings ‘production-mode’.

In automatic mode the keys mentioned below mean:
F5 Start-command (start-key)
F6 Stop-command (stop-key)
F7 Pause-command
F8 Continue-command (clear pause)

After a start-command in Manual-mode one batch will be executed. After this the machine­ status will be ‘standby’ again. The weighbin and mixbin-valve can be controlled manually.

In manual mode the keys mentioned below meaning:
F5 Step-command (One component of a batch)
F6 Reset-command (Back to the fi rst component of a batch)
F7 Empty weighbin
F8 Empty mixbin

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2.4 Production-modes

The production-mode of the blender indicates how the production will stop in automatic­ mode. This parameter can be changed using the menu (F1) ‘controller / public parameters’.
The production-mode has three options:

Continue

The blender will not stop automatically after the start-command. The blender will continue
the production, unless the blender runs out of material or an error occurs.

Weight->Alarm

If ‘Weight->Alarm’ has been chosen, a requested weight has to be given. After a start the
requested weight will be compared with ‘produced-weight’. If both are the same or the
‘produced-weight’ higher, the controller will send an alarm to the operator-interface. The
production will continue.

The alarm can be recovered setting the ‘production-weight’ to zero (0). This command is part
of the option-menu (F2) of the status screen.

Weight->Error

When using the option ‘Weight->Error’ a weight has to be given. After a start the requested
weight will be compared with ‘production-weight’. If both are the same or the
‘production-weight’ higher, the controller will send an error to the operator-interface. The
production will not continue in this case.

2.5 Mixer-mode

When all components are dispensed, the contents of the weighbin will be emptied. The
mixer in the mixing chamber, which contains the dispensed components, can be put in
different modes. Choose the menu (F1) ‘controller/public parameters’.

Normal

The mixer is off during production. If the components are dumped from the weighbin into the
mixer chamber the mixer will be on for a predefi ned number of seconds, defi ned by
‘mixerOnTime’. This parameter can only be changed if this option is chosen.

Pulsing

The mixer will pulse during production. Both on- and off-time ca be defi ned using the
parameters mixerPulseOnTime (time on) and mixerPulseOffTime (time off). These
parameters can only be changed if this option is chosen.

Off

The mixer is always off.

On

The mixer is always on, when the machine status is active.

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2.6 Dispense modes

The blender has two ways of dispensing: gravimetric and volumetric. One mode can be
selected or a combination of both. This can be defi ned choosing menu (F1) ‘controller /
public parameters’.

Gravimetric

All component of the batch are dispensed and measured separately. Gravimetric is more
accurate than volumetric, but takes more production time, ie., lower output.

Volumetric

All components of the batch are dispensed at the same time using the dispense time of each
component (calculated by the system). The components are dumped directly in the mixer
chamber. No measurement is done in this mode. Therefore this method is less accurate, but
the production time is faster, ie., maximum output

Combination

When combination is defi ned, one gravimetric will be followed by a defi ned number of
volumetric dispenses. This is defi ned by the parameter combinationRatio. This parameter can
only be defi ned if ‘combination’ is chosen. This mode has the best of gravimetric and
volumetric.

Use: normally the defi ned combination will be done (ex. 1:3). However, if the mixer chamber
is full, the process will automatically do a gravimetric dispense instead of a (possible)
volumetric one.

2.7 Batch handling

2.7.1 Production control

If a start command is given the controller will check if the blender actually can start. If a
hopper has a low-indication (optional) the controller will alarm.

Also the parameters are checked. These can be in confl ict with the recipe to be executed.
The following items will be checked (if applicable):

* Empty Regrind control

- The controlled hopper must contain regrind (according to recipe)

* Stock silo control (optional)

- Controlled hopper must contain regrind (according to recipe)

* Additive to regrind

- Controlled hopper must contain additive (according to recipe)

The blender will not start unless all conditions are met. A message will be sent to the user interface.

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2.7.2 Recipe to weight calculation

After a start-command the controller will calculate the requested weights of all components
of the selected recipe.

A recipe can be defi ned in two ways: ‘Standard’ and ‘Percentage’. These methods can
be defi ned in the recipe choosing menu (F1) ‘recipes / edit recipes’. The methods
‘Standard’ end ‘Percentage’ defi ne the relation of the components (Regrind, Natural and
Additive) in a recipe.

2.7.2.1 Method Standard

The different components are defi ned as follows:

Regrind : Percentage of the batch weight
Natural : Relation between other naturals
Additive : Percentage of the totals of all naturals

Example

Batchweight 2000.0 gr.
Regrind 20.0%
Natural 1 4
Natural 2 1
Additive 5.0%

Regrind : 20.0% of 2000.0 gr. 400.0
Naturals : naturals + additive = 80.0%
naturals + (0,05 * naturals) = 80.0%
naturals = 80.0/1.05 = 76.2%

natural 1 = 4/5 * 76.2 = 61.0% 1220.0
natural 2 = 1/5 * 76.2 = 15.2% 304.0

Additive : 80.0 - 61.0 - 15.2 = 3,8% 76.0

TOTAL 2000.0

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2.7.2.2 Method Percentage

The different component are defi ned as follows:

Regrind : Percentage of the batch weight
Natural : Percentage of the batch weight
Additive : Percentage of the batch weight

Total sum must be 100%.

Example

Batchweight 2000 gr.
Regrind 20.0%
Natural 1 60.0%
Natural 2 15.0%
Additive 5.0%

Regrind : 20.0% of 2000.0 400.0
Natural 1 : 60.0% of 2000.0 1200.0
Natural 2 : 15.0% of 2000.0 300.0
Additive : 5.0% of 2000.0 100.0

TOTAL 2000.0

2.7.3 Adding extra materials

The defi ned amount of the component defi ned in the recipes can be changed external
using some special parameters. The controller has two methods: ‘Additive to regrind’ and
‘Regrind Control’.

IMPORTANT

Addition of extra material using ‘Additive to regrind’ and ‘Regrind Control’ is only

possible when a ‘standard’ recipe is used.

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2.7.4 Additive to regrind

It is possible to dispense more additive in relation to the amount of regrind. Choose for
this defi nition menu (F1) ‘controller / public parameters’. A maximum of two hoppers
(additive) can be defi ned (additiveToRegrindHopper). The defi nition must be completed
defi ning the requested percentage (additiveToRegrindPerc).

ADDITIVE TO REGRIND

Not activated Activated with 2.0%

Component Recipe Weight (g) Recipe Weight (g)

Regrind 20.0% 400.0 20.0% 400.0
Natural 1 4 1219.0 4 1213.0

Natural 2 1 304.8 1 303.2
Additive 5.0% 76.2 5.0% + 2.0% 83.8

2.7.5 Regrind control

The fl ow of ‘regrind’ is very often not continuous due to the process. There are two
methods to adjust the amount of regrind to the actual process: ‘Empty Regrind’ or ‘Stock
Silo’.

2.7.5.1 Empty regrind Control

Empty regrind control means: keep the regrind-hopper empty. The material must be
dispensed, because otherwise another parts of the process can be destroyed (regrind return
mechanism).

Through menu (F1) ‘controller / protected parameters’ the process can be activated. After
the process is started a defi ned amount of batches (Empty regrind wait count) must be
awaited before the percentage will be increased. The percentage will be increased in
the defi ned number of steps (Dispensevariation cycl.) until the requested percentage is
reached (Dispense increase).

If not enough material can be dispensed from the regrind hopper, then regrind will be reset
to the original setting (recipe).

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2.7.5.2 Stock Silo Control

A regrind silo can have (optional) three sensors to detect high- low- and middle. If the
controller has these sensors, ‘Stock-Silo’ regrind control can be activated, choosing menu
(F1) ‘controller / protected parameters’.

If the high-sensor is true, the silo is almost full. Therefore more regrind will be dispensed.
This is the same as described in ‘empty regrind control’. This will be done until the middle
sensor is not true anymore. In a defi ned number of steps the process will dispense the
original setting of the recipe.

If the low-sensor is true, the silo is almost empty. Therefore less regrind will be dispensed.
This is the inverse as described in ‘empty regrind control’. This will be done until the
middle sensor will become true. In a defi ned number of steps the process will dispense
the original setting of the recipe.

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2.7.6 Dispensing

Dispensing of the different components will start after the calculation of the related weights.
The components are dispensed in the order as defi ned in the recipe (gravimetric only). In
volumetric mode all components are dispensed at the same time.

Every mechanical valve has a reaction time. The controller uses the ‘Hardware Reaction
Time’ to calculate the time which the dispense valve must be activated. The ‘Hardware
Reaction Time’ is the maximum active time of the valve when no material is dispensed. The
controller uses a pulse of 5ms in the following algorithm:

OpenTime = Weight [g] / dipenseSpeed [g/s]

OpenPulses = (OpenTime [s] / 0.005 [s]) + HardwareReactionTime [Puls]

After every dispense cycle the weight is measured. The weight bin must be stable before
the weight can be measured, therefore a time delay is inserted between dispense and
measuring. When the controller starts measuring the signal must be stable for at least 1 sec.
(signal within the ‘Weighbin-variationband’)

After measuring the weight of the fi rst dispense some calculations can be done, and with
the results parameters can be changed. Result is a more accurate next dispense. After the
fi rst dispense of a material one of the following situation occurs:

Dispense is correct

The difference between calculated- and measured weight is less then the dispense accuracy.
In this case extra dispense tries of this material are not necessary.

Dispense not correct (too little)

The difference between calculated- and measured weight is more than the dispense
accuracy but there is less dispensed (measured) than calculated. In this case the controller
reacts according to the chosen ‘alarm-type’. The following ‘alarm-types’ are possible:

IGNORE No extra dispense-tries. Relations within the recipe will corrected by
re-calculations.

WARNING The controller tries to reach the dispense-accuracy by extra dispenses. The
extra dispenses are limited by the parameter ‘dispenseTry’. When after a
maximum number of dispense tries, the accuracy is not reached the controller
sends a warning only to the user (= The controller continues with the next
material).

ERROR The reaction of the controller is equal to ‘WARNING’ only an error is sent
to the user when the accuracy is not reached. Now the controller waits for a
confi rmation (enter) to initiate new dispense tries of the same material. This
process goes on until the dispense accuracy is reached.

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Dispense not correct (too much)
To much material has been dispensed so there is nothing the controller can do. Of course
the relations within the recipe will corrected by re-calculations.

After the fi rst dispense try in all of the above mentioned cases a new dispense rate will
be calculated. If the measured dispenserate (measured weight / dispense time) differs from
the used dispenserate a correction can be made. A correction is only made if the difference
between the measured- and used dipenserate is less then the boundary
(dispenseRateVarBand). This method prevents the controller calculating incorrect values
e.g. if a hopper runs out of material. The new dispenserate is calculated by the next
algorithm:

dispenseRate = ((4 * dispenseRate) + (measuredWeight/dispenseTime))/5

When all components of a recipe are dispensed the contents of the weighbin is dumped
in to the mixer chamber. The weighbin dumps the material by opening a valve for a given
time. This time (weighbinDumpTime) is a parameter which can be changed. It is also
possible to start the mixer at this time (see mixer-mode). There are two conditions for
opening the weighbin valve:

Condition 1. The mixbin-vale may not be open (if present)

Dispensed material must be mixed fi rst before it can be used. Therefore the mixbin-valve
and weighbin-valve may not be open at the same time.

Condition 2. The mixerchamber may not be full

If the input-device indicates a full mixerchamber no material may be dumped into it (it
is full)

2.7.7 Calculations

In order to be able to dispense with high accuracy, the actual measured weights will be
used to recalculate the requested weight of the next component. The dispense will be
optimised if possible in order to guarantee a good batch (good relation).

IMPORTANT

Best dispense order is:

Regrind, Natural, Additive

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2.8 Datalogging

Some production data is stored. This is shown at the user interface and can also be printed.

* Batch data

- measured weight (each component)

- dispenserate of each component

- recalculation to recipe

* Total data

- Sum of batch data

* Material usage

- dispensed amount of each hopper

- percentages

The controller saves all data in battery-backup memory.