types of load
DESCRIPTION
TYPES OF LOAD. TYPES OF LOAD. CONSTANT TORQUE LOAD :. TORQUE. 100. 80. NOTE :- A CONSTANT TORQUE LOAD IS NOT NECESSARILY 100% LOAD . PERCENT TORQUE AND HORSEPOWER. 50. 100. 50. PERCENT SPEED. TYPES OF LOAD. CONSTANT TORQUE LOAD :. - PowerPoint PPT PresentationTRANSCRIPT
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TYPES OF LOAD
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CONSTANT TORQUE LOAD :
PERCENT SPEED
NOTE:- A CONSTANT TORQUE LOAD IS NOT NECESSARILY 100% LOAD
TORQUE100
50
50 100
PE
RC
EN
T TO
RQ
UE
AN
D
HO
RS
EP
OW
ER
TYPES OF LOAD
80
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automation4meConveyorsCompressorsRoot BlowersPositive Displacement Pumps
TYPES OF LOADCONSTANT TORQUE LOAD :
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VARIABLE TORQUE LOAD :
TYPES OF LOAD
0
20
40
60
80
100
10 20 30 40 50 60 70 80 90 100
SPEED IN %
TOR
QU
E &
PO
WER
IN %
TORQUE
POWER
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VARIABLE TORQUE LOAD ( Torque Varies as Square of Speed)
TYPES OF LOAD
Centrifugal PumpsCentrifugal Fans 5
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TORQUE100
50
50 100PERCENT SPEED
150 200
TORQUE
HORSE POWER
PE
RC
EN
T TO
RQ
UE
AN
D
HO
RS
EP
OW
ER
CONSTANT HORSEPOWER LOAD :
TYPES OF LOAD
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CONSTANT HORSEPOWER LOAD :
TYPES OF LOAD
• Lathe
• Grinders
• Winders
• Coilers
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ENERGY SAVING APPLICATIONS
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Key Applications Areas – The Energy Guzzlers
• Fans– AHU– Ventilation / Fresh Air – Exhaust– Cooling Tower Fans– ID / FD Fans
• Pumps– Process Water– Pressure booster pumps
• Compressors– Reciprocating, Screw,
Centrifugal
Energy Savings
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Air flow control of fan
Outlet side damper Inlet side
damper
FAN APPLICATION
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Comparison of motor power for fan drive system
100
050 100
Airflow or motor speed (%)
Shaft or power consumption
Energy saving
Inverter control
Shaft power for speed control
Damper control
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Flow Control-Affinity Laws
• Flow Speed
• Pressure / Head Speed 2
• Power Speed 3
Benefits of Flow Control… 12
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Fundamentals- Traditional
Flow control is achieved by riding the pump or the fan curve…
Throttle
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automation4meFlow control is achieved by riding the System Curve…
Fundamentals- Evolution
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PRES
SUR
E
VOLUME
THROTTLE CONTROL
B
A
O
F
E
D
C SPEED CONTROL
ENERGY SAVING
= SHADED REGION
= AREA (OEAD) - AREA (OFCD)
PRINCIPLE - ENERGY SAVING BY SPEED CONTROL OF PUMPS
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The energy saving effect to the pump type
00.5 1.0
Flow rate Q (P.U.)
Head H (P.U.)
Axial pump
As shown in the figure, the sharper the pump characteristic is i.e., the bigger the comparative speed is, the bigger the 1st energy saving effect becomes.
1.0
2.0
Energy-saving effect
mixed flow pump
Centrifugal pump
System resistance
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PRINCIPLE - ENERGY SAVING BY SPEED CONTROL
As Per Affinity LawsAs Per Affinity LawsFlow (%)Flow (%) HP (%)HP (%)
RequiredRequired
100100 100100
7575 4242
5050 12.512.5 17
automation4meCompressor
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Compressors• Operates in a load/ unload cycle.
Time
Load
100%
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Conventional compressor system work between two set pressures, resulting in pressure generated being higher than the pressure required in the system.
TIME
PRE
SSU
RE
POW
ER
110PSI
90PSIMINIMUM SYSTEM
PRESSURE REQUIRED
20 PSI
100% FULL LOAD POWER DURING LOAD CYCLE
20-30% OF FULL LOAD POWER DURING UNLOAD CYCLE
LOAD UNLOAD
TIME
100PSI
Compressor–Load/Unload Control
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Energy consumption as high as 20-30% of full load power during unload period.
Pressure in the system is much more than the minimum system pressure required, resulting in extra power consumption and wear and tear of the mechanical system.
20PSI extra pressure in the system, results in 10% extra power consumption.
DOL or star/delta starting sequence on a motor creates a power surge in electrical system.
Disadvantages of Traditional Compressor:
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Typical Schematic
AC MOTOR AIR COMPRESSOR
AIR
RECEIVERVARIABLE
SPEEDAC DRIVE 4-20 mA/ 0-10V PRESSURE FEEDBACK SIGNAL
3 Ph./ 415V Supply
ToPlant
PRESSURETRANSMITTER
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Variable pressure setting possible.
Accurate pressure control.
No unload cycle, thus reducing power consumption typically by 20 to 30% of full load power.
Soft start with inverter control, power to the motor is increased progressively, avoiding peak power demand in the electrical system.
Advantages with Inverter Control:
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