Showing posts from July, 2016

Failure analysis of job insecurity diesel generator starting

After the diesel generator starting job insecurity Failure Analysis:After cranking speed diesel generator fluctuated, usually because the fuel adjustment system failure caused.
Failure reason:1 each cylinder diesel generator work poor, leading to deflationary pressures are not the same for each cylinder.2 fuel supply system with air, water or poor oil supply.Associated with each cylinder plunger large amount of oil within the high pressure fuel pump 3.4 internal speed governor stretched spring elastic weakened, so that the onset of the change speed control function.5 governor not meet the minimum speed.6 Governor inner rotating parts imbalance or cooperative gap is too large.7 governor speed reach the rated speed.
Fault Solution:Oil Pan Oil dipstick 1 pairs within view, the investigation is not oil viscosity is too low or too much amount of oil, so oil into the combustion chamber after burning and evaporated to oil and gas is not discharged from the exhaust pipe. But by looking at t…

How to calculate 7.5kw motor rated current

7.5KWthree-phasemotors(Y2series)Ratedcurrent:14.9An(2-pole),15.6Ann(4-pole),17.2Ann(6-pole),17.8Ann(8-pole).No-loadcurrent is about30to 50% of the ratedcurrent.

Calculation method:

P = 0.85 * 1.732UI = 0.85 * 1.732 * 380 * II = 13.4overthe algorithm7.5kwthree-phase asynchronousmotors.0.85power factor.

The most simple and safest delta voltage starting circuit diagram


What is the difference between circuit and magnetic circuit

What is a circuit?
EMF(voltage)under the pathof the currentsflowing through the circuit.Usuallyconsists of a power supply,loadandswitchit into threeparts.Themagnitudeanddirection of the currentflowing through the circuitthecircuitdoes notchangewithtime,called the DCcircuit.Themagnitudeanddirection of the currentflowing through the circuitcircuitovertime,called the ACcircuit.
Magneticcircuitiswhat does that mean?
Whenyouironcorecoil,magnetomotive force generatedby themagneticflux,mainlyconcentratedin the pathspecifiedby the core,thispathiscalled the magneticcircuit.Byexcitationofmagneticcircuit of directcurrent,called the DCmagnetic

What is a PLC? PLC What does it mean?

Manybeginnerstoabbreviation(PLC)toworry about.PLC iswhat,whatis a PLC?What does PLC mean? Is actuallyverysimple,officialdefinitionsofsame,Iunderstand.What's PLC?PLC isanintelligentcontroller,is a computer(PC).PLC is a programmable logic controller.PLC programmablecontrolleris:EnglishuniversalProgrammableLogicControllerPLC, in Chineseknown asprogrammablelogiccontrollers,isdefined as anumber-crunchingoperationelectronicsystem,speciallydesignedforapplicationsinindustrialenvironment.Itusesaprogrammablememoryforitsinternalstoredprocedures, and performlogicaloperations,sequencecontrol,timing,countingandarithmetic