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Dear Ally ;
I think that you should do the necessary configurations for paper's size in the Software it-self as the other software, and certainly you have an A3 printer, but if you haven't this possibility in the Software you can't do it.
Regards.
Mike said:
we are a generating company , we export power to offtakers . In addition we have sizeabale inhouse recative loads of Large Induction Motors.
Do you see that by installaing capacitor banks for compensating against IN House Motor Loads, will we be saving in terms of off loading Generator foe Reactive load whcih in turn will be able to improve PF and can export more MW.
Thanks and Regards
Mike
Dear ;
Definitely yes, noting that when the PF is improved the available power in kVA at generating side will be more .
rafi201 said:
that means 4KW OF POWER =1250 HOUSES
Dear Rafi ;
The installed power depends on the house's type, for small house ( limited equipments ) is around ” 2.5-3kW “, for standard house is around to ” 4kW “, and can be achieved to ” 6-10kW ” for big house, but for a villa it will better to know exactly what equipments have been installed. But in all case, we should take into consideration the 2 important factors ” ku & ks ” depending on the houses' number.
majid_khan said:
A circuit breaker is tested according to IEC Specification of 40kA Short Circuit Current Test and passed the test.
How many times in his life that circuit breaker will withstand short circuit conditions before being damaged, is their any approximate limit?
Dear ;
The ” IEC947-2 ” standard doesn't define any number, but we should know if this value ” 40kA ” for a corcuit breaker is for ” Icu or Ics “, because there are some differences between these 2 tests' procedures.
Vidhyut S. said:
What effect will be seen if we connect two busbars having different frequency voltage?
i know that we can't do this..but what will be the effect if we do so.
Dear ;
Please clarify if there's a difference in the Voltage or Frequency.
rafi201 said:
SIR GIVE ME SOME MORE ELECTRICLA TIPS FOR REDUCING OPERATIONAL COST OF THE PLANT FROM UR EXPERIENCE…………………
Dear Rafi ;
To reduce the operational cost for any plant, all information about the plant should be known with the single line diagram, and even the working and timing system and of the plant, then a special study will be done to define where we can reduce and what equipments should be used. Noting that there's special companies that can do this study.
DerDishant said:
when i am connecting the elctrical water heater, within few seconds the supply in my home is getting tripped…
This never happened before….it was working very well….but now i think the connecting leads are got corroded and thats why the earthing wire is getting actuated….how should i stop this?
I tried to remove the earthing connection and just connected the +ve & -ve wires, but still getting the fault…
Dear ;
As each Electrical Water Heater contains a Heater Resistance, I think that the insulation layer around the resistance is damage, so, there's now a short circuit ( between phase & neutral ) with a connection to the body, for this reason :
1 – You remarked that the PE ( earthing wire ) is actuated.
2 – Normally, the value of the short circuit's current is too big comparing to the nominal current, it will trip the protection device that provoke at your case the tripping of the power supply ( it seems that there's no a special device for this water heater ).
The best solution is to change, if possible, the heater resistance.
rafi201 said:
HI,
ENGINEERS,
HOW MANY HOUSES CAN HAVE ELECTRICITY WITH 1MW OF POWER?
Dear Rafi ;
To define the number of houses, we should absolutely know the following :
1 – The avearage value of Installed power in a the house.
2 – The utilization factor ” ku ” that will be for this case ” ku = ≈0.5 “
3 – The diversity factor ” ks ” that will be for this case” ks = ≈0.4 “
Assume that the installed power in a standard house is ” 4 kW ” and all houses are supplying from the same source, so the number of houses ” N ” is :
1 x 1 000 000 = 4 000 x 0.5 x 0.4 x N
N = 1 000 000 / 800 = 1250 houses
rafi201 said:
please tell me the source for downloading electrical softwares like design,control,testing,erection……………
Dear Rafi ;
If you need an Electrical Software calculation for LV network, you can either ask Schneider Electric office in your country for ” Ecodial… “, or ask Legrand office for ” XLPro² Calculation ” for calculation of the LV network and also for ” XLPro² ” designing of LV Switchboards.
By the way, you can download free the ” Ecodial… ” from the Web-Site of Schneider Electric.
Dear Rafi ;
I understand your situation, and accordingly to your application, I want to draw your attention to the following :
1 – If the motor consumes at full load around ” 500A ” it's certainly ” Over-Loaded “, because his nominal current should be around ” 375A ” if ” Cos φ = 0.85 “
2 – If the motor on no load consumes around ” 200A ” that means there's a load but not full, because this kind of motor should consume without any load around ” 8-10% ” of his nominal current.
3 – For this kind of application, you should use ” ATV71HC25N4 “, but be attention of the VSD Thermal Protection that will trip if it's adjusted exactly at the motor's nominal current.
4 – If the motor runs idle ( with the minimum load ) on the same nominal speed ( nominal rpm ), by using a VSD the benefit will be moderate, but if you have the possibility to reduce the speed when it runs idle you will have more benefit.
rafi201 said:
Dear Engineers,
How to start a 220KW ac induction motor by using AC DRIVES TO REDUCE POWER CONSUMPTION?
1.Are they any AC drives?please mention their price and specifications?
Dear Rafi ;
Certainly, there's a Variable Speed Drive for even more than 220kW, I will mention below the references for ” Schneider Electric ” :
– ATV61HC22N4 : the transient torque for this VSD is ” 120 … 130% “ of the nominal torque for 60 seconds
– ATV71HC25N4 : the transiant torque for this VSD is ” 170% “ of the nominal torque for 60 seconds, and ” 220% “ for 2 seconds
So, depending on your application if you need standard or high torque you can do the choice. Noting that for each one there's many options that you can add.
For the unit price, you can ask the Schneider Electric office or any distributors for them in your country.
Rem. : if you need more information about them please send me an e-mail at hagersg@aloola.sy
Regards.
Dear ;
Even the schematic diagram is not too clear, but i will try to explain what could be happen.
As the RCBO tripped, and we know that all RCBO have ” Thermal & Magnetic protections + Earth Leakage protection ” there's 2 possibilities :
1 – The tripping order was from ” Thermal or Magnetic protection ” and in this case we had either an over-load or short circuit, where we can know which of them as follow : if you tried to close it without success for a few minutes in this case the tripping's order was from Thermal protection, or it closed but immediately re-tripped in this case the tripping's order was from Magnetic protection.
2 – The tripping order was from Earth Leakage protection, and in this case we have 3 possibilities :
A – There's a leakage current, either permanent or transient, more than ” IΔn “, if permanent you can't re-close the RCBO, but if transient you can re-close it again.
B – We know all the all kind of PC have a transiant leakage current and a big value of Crest factor that cause some distortion of the current, for these reasons we use for this kind of application a special RCBO or RCCB that have ” High Immunity “.
C – At the moment of supplying a PC the inrush current is, in some case, bigger than the Magnetic protection, so, the RCBO will re-trip immediately. for this reason it will be better to use ” C curve ” or in some case ” D curve “.
To be able to clarify more, it will be better to have the Single Line Diagram, because as you mentioned that there's 800A MCCB, then 100A MCCB and 100A I Switch, then 63A MCB and 63A Switch, then the RCBO or RCCB.
Dear ;
I said before that the using of a special pole for Neutral is depending on the used Earthing System in your software house, as in some Earthing system the Neutral should be Switched-On & Off with the phases poles, so, the advantages and disadvantages are for the Earthing system and not for the Neutral pole. For exp. if you used ” TN-C ” you can't never use the 4th pole whatever the advantages.
In your case, it will be better to ask any Electrical Engineer in your place about the used Earthing system, then will decide if you should use the 4th pole in the circuit breaker.
frenchma1221 said:
Where can i find electrical engineering softwares for free download?
Dear ;
It's simple, you can find it on the Web-site of ” Schneider-Electric “, the software is ” Ecodial… “, or you can contact the Schneider Electric offic in your country to have for free CD.
Also, you can contact Legrand office in your country to have ” XLPro² calculation “.
A123 said:
the 3 phase power tansformer load loss measured by 3 wattmeter method. the total losses is sumation of w1+w2+w3=total losses
but as 3 kimbs of transformer is identical but w1 w2 w3 are not identical why this happens
Dear ;
You talk about the ” Copper Losses “, and we know that losse for each coil is : I² x R, that means the value is depending on 2 factors. Assume now that R has the same value for all coils ( it's 100% theoric ) the values for W1, W2, & W3 are depending on the circulated current in each coil, so, even if the currents are the same the R1, R2, R3 haven't 100% the same value.
