Sterling 882.00722.00 Manuel D’Utilisation

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Chapter 2: Functional Description 
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•  Optional Ethernet communications 
System Component Description 
This section describes the various components of the rate monitor system. 
Extruder Inductive Proximity Switch 
The extruders RPM must be reported to all GH, GH-M, and GH-F Systems for them to 
function.  To accomplish this, an inductive proximity switch is provided to let the controller 
know the RPM of the extruder.  This switch should be field mounted in an appropriate way to 
read the extruder’s true RPM.  It is important this switch is reading the actual RPM of the 
Extruder, and not an RPM before a gearbox, for example.  Chapter 3 will detail the 
installation and wiring of this component.  Because it is field mounted, wiring of the 
proximity switch will NOT be done at the factory and we do not provide any custom 
mounting brackets for your application as these vary depending on the equipment.  
This measurement can also be achieved by writing the extruder’s rpm through 
communications (see document at the end of this manual for details, NOT AVAILABLE 
FOR GH-F FEEER UNITS).  If this is done through communications then it eliminates the 
need to install the extruder proximity switch. 
Surge Hopper 
The surge hopper is located on top of the GH frame.  These hoppers store a supply of material 
to fill the weigh hopper. The surge hopper is sized based on the total throughput of the 
extrusion rate monitoring system.  Each surge hopper contains a 24V DC solenoid that is 
used to open and close the internal dump cone.  The internal urethane dump cone is 
mechanically opened and closed with a compressed air cylinder. 
The GH’s surge hopper does not include any level indication devices as standard equipment. 
Optional surge hopper low-level sensors are available.  The GH controller will alarm if it runs 
out of material while trying to fill the weigh hopper, but low-level sensors will alert floor 
personnel to the problem sooner.  If an optional low-level sensor is purchased, it will activate 
a visual alarm.  This optional proximity switch can be mounted anywhere the customer 
desires and is not mounted unless specifically requested. 
The refill system is equipped with a manual key switch to open and close the surge hopper.  
This three position key switch is located on the front of the PLC enclosure. 
Figure 5: Typical Surge Hopper 
 
 
 
 
 
 
Figure 6 Refill Switch Positions 
Position 
Description 
AUTO  
The rate monitor controller automatically controls surge hopper 
functions.