treinamento drives rockwell automation,

1. Break-Out Session Name: Engineering Assistant Tools
Lab Developer: Josh Olive, Roman Lichon
Lab Exercise: Lab 1 – Sugar Centrifuge
Application
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2. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
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Table of Contents
BACKGROUND ............................................................................................................................ 2
LAB OBJECTIVES ............................................................................................................................. 2
CONVENTIONS USED IN THIS LAB ..................................................................................................... 2
EQUIPMENT LIST.............................................................................................................................. 2
LAB SETUP ...................................................................................................................................... 3
SECTION 1: SUGAR CENTRIFUGE APPLICATION .................................................................. 4
MACHINE DESCRIPTION ................................................................................................................... 4
MACHINE CYCLE .............................................................................................................................. 4
GIVEN INFORMATION ........................................................................................................................ 5
OBJECTIVEL .................................................................................................................................... 5
USE AVAILABLE TOOLS ..................................................................................................................... 5
SOLUTION ....................................................................................................................................... 9
Conventions Used in This Lab
 ATTENTION: Identifies information about practices or circumstances that can lead to
personal injury or death, property damage or economic loss. Attention statements help you
identify a hazard, avoid a hazard, and recognize the consequences.
 TIP: Identifies information that is helpful, but not necessary, in completing a task.
 FYI: Provides additional information regarding the lab equipment, but is not needed to
complete the lab.
Background
Engineering Assistant is a software tool offered, by the Commercial Engineering Group with Allen-
Bradley Standard Drives Business, as an aid and guide to analyzing process applications by providing
general tools for unit conversions, electrical power formulas, inertia and power calculations, and
specific application calculator tools that prompt specific input necessary to size drives and motors.
Lab Objectives
This lab is designed to familiarize the student with sizing a drive/motor for a centrifuge
application using the Centrifuge Calculator offered within Engineering Assistant.
Equipment List
 (1) PC with the latest Engineering Assistant software.

3. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
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Lab Setup
1. Study the application scenario described for what information and what unit of
measurement is provided.
2. Outline a method organizing what is needed to achieve the goals of the Lab.
3. Choose the appropriate tools from Engineering Assistant that can assist your effort.
4. Graph visual results
5. Save and retrieve Results.

4. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
Section 1: Sugar Centrifuge Application
Machine Description: This machine is used to reduce
moisture content prior to additional processing. The centrifuge
works by spinning the sugar slurry (massecuite made from
either sugar cane or sugar beets) at a high speed. The
centrifugal force pushes the slurry to the side, forcing liquid through perforations in the
basket while solids are retained inside. The basket consists of a fine screen or cloth.
The basket resides inside the centrifuge, close to the centrifuge wall. The remaining
solids (cake) can then be washed and spun at higher C’s to achieve a relatively dry
cake. The resultant cake is then discharged through the bottom of the basket by
means of a single motion plow like mechanism.
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Machine Cycle:
1. Accelerate to a low speed and fill the centrifuge with the slurry.
2. After loaded, accelerate to full speed (also called spinning/centrifugal speed).
3. Decelerate to a minimum speed to unload. At this point the remaining sugar is scraped out of
the centrifuge’s basket.
Total typical cycle time is 3 minutes, which equates to 20 cycles per hour minimum.
Speed Profile
1200
1000
800
600
400
200
0
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
Time (sec)
RPM
Spinning (Centrifuging)
Filling
Unloading
1445 kgm2
700 kgm2
1150 kgm2

5. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
J RPM
  
accel t
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Given Information:
Motor:
Power: 330 kW
Base Speed: 888 RPM
Efficiency: 95.5 %
Current: 535A
Torque: 3581 Nm
Voltage: 460V
Base Freq: 60 Hz
Machine:
Cycles per hour: 22
Inertia empty: 700 kgm2
Inertia full: 1445 kgm2
Inertia after spinning: 1150 kgm2
Fill speed: 180-200 RPM
Fill time: 15 Sec
Accel time to top speed: 40 Sec
Spinning (Centrifuge) Speed: 1100 RPM
Spinning (Centrifuge) Time: 35 Sec
Decel time from Spinning Speed to Unload Speed: 33 Sec
Unload Speed: 50 RPM
Unload Time: 40 Sec (includes Accel Time to Loading Speed)
Objective:
Determine drive size and dynamic braking requirements. Offer an effective solution.
Use Available Tools:
Use the Centrifuge Calculation Tool to calculate torque and power requirement. Based on formula:
accel accel
t
J
M


 

30
 
where M is in Nm, and J is in kgm2
 TIP: Open the Centrifuge Calculator tool with in Engineering Assistant to determine
what is needed and units of measure to work with. Also explore other tools that
may help working with the data given or missing.
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6. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
Try converting the given data to be entered into the calculator tool, without just copying the values
shown. The following screen views are for confirmation, that you understand the data you are
entering.
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7. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
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8. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
 TIP: Note that if you did not use the given information to calculate the Initial Accel
Time correctly and subtract it from the T6 Unload time, the tool warns that 22
cycles cannot occur within the time period. So adjustments need to be made.
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9. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
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Solution:
 Perform checks for peak torques and peak currents. Note that peak torque demanded
happens to be regeneration torque at 1100 RPM in the constant HP range is 133.44 %. This
may be okay, since most motors are designed to at least generate 200% torque for a short
time at rated speed. This application duration for that level of demand is relatively short
compared to the entire cycle, should be feasible to operate at, but requires due diligence to
verify that the motor design spec sheet supports the demand with room to spare.
 Graph the Results. What becomes visually noticeable during the cycle?
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10. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
 Note that the equipment will be operating at 3822 Nm / 3581 Nm = 107% (2819 lbft / 2641 lbft
= 107% from Results Tab) of motor torque for about 33 seconds out of the entire cycle. Will
the motor be able to handle this? Probably. But, if necessary, we could extend the decel time
from 33 to 36 seconds and shave off some time somewhere else. Looking at motor data could
be very important to make this decision.
 Now that the motor is sized okay, the 535 Amp rating of the motor and the graph , should help
determine the drive to specify. (But not necessary for this Lab)
 By nature, centrifuges have a significant percent and duration of its cycle regenerating energy.
This makes regenerating energy back onto the power source much more feasible and
justifiable. So this tool promotes a solution based on the present 1336R for dynamic braking.
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11. Engineering Assistant – Tools
Lab 1 – Sugar Centrifuge Application
Even if the 1336R was not to be chosen, the results provide peak torque and current
information that can be used to size other dynamic braking hardware solutions.
 Try to Save and then retrieve the file by accessing File in the upper left corner of the tool. This
allows for several variation studies to be done and to be able to come back and continue at a
later date. Note that printing results can also be done to facilitate communication.
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Design Limitation Insight:
 Using (3) 1336Rs in regen brake mode in parallel. This can only be done in regen brake
mode. Based on testing, we can’t get much overload out of 1336Rs in this mode without
possibility of tripping on overcurrent. Common mode reactors are used to help reduce peak
currents on AC line from regen brakes.
 Whenever designing or specifying more than one 1336R unit per dynamic braking
application, consult with the factory about special precautions.
 STOP HERE. This is the end of the lab.