This document includes confidential data that shall not be duplicated, used, distributed, or disclosed for any purpose unless authorized by Siemens. SIEMENS Process Sensors Level & Weighing Technologies This document includes confidential data that shall not be duplicated, used, distributed, or disclosed for any purpose unless authorized by Siemens. Belt Scale Basic Theory
51
Embed
This document includes confidential data that shall not be duplicated, used, distributed, or disclosed for any purpose unless authorized by Siemens. SIEMENS.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
This document includes confidential data that shall not be duplicated, used, distributed, or disclosed for any purpose unless authorized by Siemens.
SIEMENS Process Sensors Level & Weighing Technologies
This document includes confidential data that shall not be duplicated, used, distributed, or disclosed for any purpose unless authorized by Siemens.
Belt Scale Basic Theory
Page 210/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Theory
There are four essential components to any conveyor belt scale.
Weigh Bridge
Page 310/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Theory
There are four essential components to any conveyor belt scale.
Weigh Bridge
Speed Sensor
Page 410/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Theory
There are four essential components to any conveyor belt scale.
Weigh Bridge
Speed Sensor
Integrator
Page 510/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Theory
There are four essential components to any conveyor belt scale.
Weigh Bridge
Speed Sensor
Integrator
Conveyor
Page 610/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Integrator operation
The design of all belt scales is based on the formula
LOAD X SPEED = RATE
Load units are in lbs / ft
Speed units are in ft / minute
Pounds Feet Pounds
Foot Minute Minute
Belt Scale Theory
X =
Belt Travel
Material Load (lbs/ft)
Belt Speed Sensor
Page 710/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Integrator operation
The design of all belt scales is based on the formula
LOAD X SPEED = RATE
Load units are in lbs / ft
Speed units are in ft / minute
Pounds Feet Pounds
Foot Minute Minute
Belt Scale Theory
X =
Belt Travel
Material Load (lbs/ft)
Belt Speed Sensor
Page 810/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale TheoryD
irect
ion
of S
tret
ch
Weigh bridge operation
Strain gauge theory A thin wire is coiled so that as the
metal it is attached to is stretched the wire is made longer and thinner
The electrical resistance of the wire is related to the cross-sectional area of the wire
The change in resistance is proportional to the amount the load cell metal is flexed
Page 910/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Theory
Weigh bridge operation
Load cell theory Load cells are steel frames with
strain gauges mounted at points where the load cell is designed to flex
The parallelogram load cell is designed for parallel sides to stay parallel and only vertical forces are measured
Weight
Page 1010/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Theory
Shaft Mounted Speed Sensors
Speed sensor operation
Shaft mounted speed sensor A slotted disk rotates through an
optical encoder
The slotted disk breaks the encoder light beam to produce an output pulse proportional to the speed of the shaft rotation
Page 1110/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Theory
Trailing Arm Speed Sensors
Speed sensor operation
Trailing arm speed sensor A gear rotates near a proximity
switch
As the teeth of the gear pass the proximity switch a pulse is generated
The output pulse is proportional to the speed of the belt
Page 1210/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Theory
Belt Travel
Material Load (lbs/ft)
Belt Speed Sensor
RateLoadSpeedTotal
Integrator operation
Receives material load information from the weigh bridge
Receives belt speed information from the belt speed sensor
Provides HMI information Rate
Load
Speed
Total
This document includes confidential data that shall not be duplicated, used, distributed, or disclosed for any purpose unless authorized by Siemens.
SIEMENS Process Sensors Level & Weighing Technologies
This document includes confidential data that shall not be duplicated, used, distributed, or disclosed for any purpose unless authorized by Siemens.
Belt Scale Products
Page 1410/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Products
Siemens MBS Weigh Bridge
Unique modular design allows easy installation
Easily retrofits to existing equipment
Low cost
Accuracy: 1% over 3:1 turndown
Capacity up to 1600 TPH
Belt speed up to 600 ft/min
Page 1510/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Products
Siemens MUS Weigh Bridge
Easy installation
Easily retrofits to existing equipment
Accommodates conveyor widths up to 48”
Rugged nickel plated steel loadcells
Accuracy: 0.5 to 1% over 4:1 turndown
Capacity up to 5000 lbs/hr Belt speed up to 600 ft/min
Page 1610/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt
Belt Scale Products
Siemens MSI Weigh Bridge
Parallelogram loadcells allow high accuracy without the need for pivots or check rods
Unique design allows easy installation
Easily retrofits to existing equipment
Stainless steel loadcells for maximum reliability
Accuracy: 0.5% over 5:1 turndown
Page 1710/31/2008 Siemens AMD
Confidential - for Siemens authorized use only. Boisvert/Dronette/Jenkins/Sonnier Level_Weighing_Seminar.ppt