- #1
davehnc
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What equations should I use for an energy audit of an electromechanical system?
- Thread starter davehnc
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In summary, the person is having trouble selecting the proper equations for each stage and would appreciate help from someone who knows what equations to use.
- #2
berkeman
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davehnc said:
Welcome to the PF.
Can you show the equations and your solutions for the parts that you have done so far?
- #3
davehnc
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Equations used so far
Q1: I USED EQUATION P/real=V*I*Cos ∅
P/real=340*4.24*Cos 45
P/real=1019.37 (W)
Q2:I USED EQUATION PE=MGH (mass of water =1000)
PE= 1500*9.81*10 (gravitity =9.81)
PE= 147150 (Joules)
Q3:I USED EQUATION Mass Flow= Mass/time
= 1500/480 ( 8mins =480 seconds)
= 3.125Kg/s
??Q4:1 USED EQUATION P=I*V
=4.24*340 OR should i of used Pout=Work done /time
= 1441.6 =147150/480
=306.56(watts)
??Q5 I WILL USE EQUATION Power out/Power in *100 to establish my efficency
Im not 100% that I've used the correct EQUATIONS , as each question draws on your previous answer , Any help would be appreciated. Thanks.
berkeman said:
Q1: I USED EQUATION P/real=V*I*Cos ∅
P/real=340*4.24*Cos 45
P/real=1019.37 (W)
Q2:I USED EQUATION PE=MGH (mass of water =1000)
PE= 1500*9.81*10 (gravitity =9.81)
PE= 147150 (Joules)
Q3:I USED EQUATION Mass Flow= Mass/time
= 1500/480 ( 8mins =480 seconds)
= 3.125Kg/s
??Q4:1 USED EQUATION P=I*V
=4.24*340 OR should i of used Pout=Work done /time
= 1441.6 =147150/480
=306.56(watts)
??Q5 I WILL USE EQUATION Power out/Power in *100 to establish my efficency
Im not 100% that I've used the correct EQUATIONS , as each question draws on your previous answer , Any help would be appreciated. Thanks.
Last edited by a moderator:
- #4
gneill
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For Q1 I think you'll want to use RMS values of voltage and current if you're looking for power. The supplied diagram gives them as Peak values.
Q2 is a bit vague, asking for "The energy of liquid". presumably they mean the gain in gravitational potential energy as you've done it.
For Q4, I guess they're looking for the rate of mechanical work being done, since lifting the water is the 'output' of the system.
For the rest of the questions, I'm afraid that I'm not very familiar with the jargon or conventions involved in fluid/electromechanical system audits...
So, for example, I'm not sure what would be included in the 'specific energy' of the water leaving the pump; Does it include per unit volume kinetic energy and pressure? Gravitational potential energy too?
Q2 is a bit vague, asking for "The energy of liquid". presumably they mean the gain in gravitational potential energy as you've done it.
For Q4, I guess they're looking for the rate of mechanical work being done, since lifting the water is the 'output' of the system.
For the rest of the questions, I'm afraid that I'm not very familiar with the jargon or conventions involved in fluid/electromechanical system audits...
So, for example, I'm not sure what would be included in the 'specific energy' of the water leaving the pump; Does it include per unit volume kinetic energy and pressure? Gravitational potential energy too?- #5
davehnc
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Yeah, it is rather vague, but I'll motor on with what I've got... The questions seem to reflect on the answers to the previous ones... Thanks anyway D 
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FAQ: What equations should I use for an energy audit of an electromechanical system?
What is an energy audit of elec/mech?
An energy audit of elec/mech is a detailed analysis and assessment of the energy usage and efficiency of electrical and mechanical systems in a building or facility. It involves evaluating the energy consumption, identifying potential areas for energy savings, and recommending improvements to reduce energy waste and costs.
Why is an energy audit of elec/mech important?
An energy audit of elec/mech is important because it helps identify areas for energy savings and cost reduction. By analyzing energy usage and efficiency, the audit can pinpoint specific systems or equipment that may be consuming excess energy. This information can then be used to make targeted improvements and upgrades, leading to energy and cost savings in the long run.
Who should conduct an energy audit of elec/mech?
An energy audit of elec/mech should be conducted by a qualified professional or team with expertise in energy efficiency and building systems. This could include mechanical or electrical engineers, energy auditors, or sustainability consultants.
How is an energy audit of elec/mech conducted?
An energy audit of elec/mech typically involves a comprehensive review of building systems, equipment, and energy usage data. This may include on-site inspections, data collection and analysis, and interviews with building occupants. The auditor will then provide a detailed report with findings and recommendations for energy-saving measures.
What are some common recommendations from an energy audit of elec/mech?
Common recommendations from an energy audit of elec/mech may include upgrading to energy-efficient lighting and HVAC systems, implementing building automation systems, and improving insulation and weatherization. Other recommendations may include behavioral changes, such as turning off lights and equipment when not in use, to reduce energy waste. The specific recommendations will depend on the findings of the audit and the unique needs of the building or facility.
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