Oh, in fact I had meant DC :) just to set the relation between the current and the holding force of an electromagnet in my head. It is for sure that as the force increases the current must increase but I think every current will create a force to hold a certain weight, but even if the weight is...
Hello I imagine such a circuit. I have a 5 amper circuit ad a 50 volt source voltage and this circuit feeds only a coil which lifts say a certain weight . Now what I wonder is what happens if I let the weight drop using my hand. Does the current keep on being 5 amper again or it decreases?
no I mean with soft-loading a scheme in which a load is fed by both the utility and genset at the same time and say a genset is operating and utility is off and due to the reappearance of utility for example we take the load from genset slowly and transfer it to the utility in the final stage...
imagine it please, we have three gensets paralleled while we have three transformers which have separate buses. So there is a unique busbar and its voltage conditions while three separate transformers voltage conditions. As far as I know soft-loading is a mains-genset parallelling isnt it? ?s...
Hello, I want to ask you about a system in which there are three transformers and 3 gensets all have the same KVA respectively, I mean the back-up gensets are rated the same KVA with the tranformer to which they belong, Of course xformer-genset groups have different power ratings from each other...
Hello, I wonder if paralleling UPS's requires continuity of neutral all the time, ?t was said to me that with busbar feeding of n+1 ups operation caused problems (I dont know the details to much) since busbar breakers was breaking neutral of the ups'es . So I ask you if there is such a situation...
Hi, I am hesitating in this issue (POWER FACTOR CONNECT?ON CAPAC?TORS' L?NE PROTECT?VE FUSE RAT?NG )since I am not sure to which criteria we must select the fuses. I mean must we use a motor fuse since the in rush current makes necessary that a delaying type fuse is used. If this is so for...
Hi, I want to learn about the design of harmonic filters. I read through some info about it but unfortunately I could not get the logic of the sizing of the filter. Say I have a system dominated by 7. harmonic current. I want to learn two things.
Firstly, is there any relation between the...
Hello ,I wonder how these two operate together? They operate parallel or a in a different way? I did not see any example of this till now. Please tell me about this roughly...
hi, we use Phase+neutral breaking MCB in isolated neutral systems. I wonder one thing.
For a 120 volt say 6 A circuit is switched by 6 A MCB
so for a 120 volt 6 A circuit ?solated neutral circuit if mcb is rated 6 amper it means it has two contacts of which each has the same capacity of the...
Dear electricpete what does this mean? I think this sentence is not clear much:(if you have a circuit with resonant frequency close to resonance than the total initial energy stored in coil inductance and coil capacitance will be large and it will take a long time to dissipate in system...
Also it is stated here that "Franklin recommends that any time there is more than
300 feet of cable between the contactor and the control
switch, a capacitor should be added across the contactor coil"
so adding a parallel capacitor means we aggreveate the situation we can say , just looking at...
Hi, Can you tell me how can a parallel capacitor added to the control circuit lessen the effect of a high-residual-voltage occuring due to line-line capacitance here. I know that added capacitor means a higher total capacitor and it will create a bigger voltage and a longer time duration...
is it possible that 10 volt drops between source and equipment input ? Is not it a bit large number ? I guess you mean if an equipment needs 110 volt into it ,it must be fed from a 120 volt source (No-load or full load voltage ? ) true?
