But where goes the electrons ?

<blockquote class="imgur-embed-pub" lang="en" data-id="a/1PNNbP6" data-context="false" ><a href="//imgur.com/a/1PNNbP6"></a></blockquote><script async src="//s.imgur.com/min/embed.js" charset="utf-8"></script>

https://imgur.com/a/1PNNbP6

Unsure if the INGUR screenshot will appear. You had 3 wires connected at one central point, each with a Ampmeter. 2 of them shows zero while one shows zero, that is impossible...

I've got plenty of cases like this, and now also mosfets with strange bevahiours, unsure if my circuit is bad or CircuitLab having real problems

by Henri47
July 31, 2020

Obviously, I can't have the hope to use this soft for simulation.... few things works normally... mosfet that keeps conductive even if you reverse voltage on dc simulation (by the way using DC sweep it works as should) ampmeters that does'nt show the amps at all, on same wire one would show, the other would not (and yes they were on "show amp mode"

non activated mosfets fails so what we can do...

really I think I waste my time around it. it had plenty bugs apparently. I have purchase components and try in the real world.

at leas CircuitLab is very useful for schematic drawing... Simulations may work sometimes if the circuit is very simple maybe...

by Henri47
July 31, 2020

1] You say that you have "... plenty of cases like this ...". Are you able to show us a CL schematic which has an example problem?

2] I did two particular checks with circuit Test2, while looking at the ammeters and the figures in DC Solver. (I clicked on "Run DC Solver" after any change to the circuit.)

2a] I reversed the polarity of V7 and found that the mosfets turned from ON to OFF as expected.

2b] The 2 ammeters showed currents that were the same as each other, and with values consistent with mosfets on/off.

All seems fine for [2]: the simulations are exactly as I would expect.

I hope I can reassure you that in my experience of CL (about 6 weeks to date) it is able to handle some very complex simulations, providing much useful information.

by EF82
July 31, 2020

Thank you very much for your help here. an example with faulty ampmeters ( I just use the one that was impossible to obtain a correct Ampmeter reading , and put again an Ampmeter, and .... continues to fail ! look yourself AM13 : 30A AM15: 4.286 AM12: 4.286 how is it possible ? where goes the 30A then ?

by Henri47
July 31, 2020

and also : look at the P channel mosfets AM13, AM15,AM12 : they receive at gate a positive 18V relatively to the source how can they let Amp flow ?

by Henri47
July 31, 2020

I just take a look on Test2, as you worked on it too. according to me, the mosfets are not working as should. with V7 = 20V, Ampmeter shows 30A this should not, because it's a P channel mosfet then if you want to shut it off, you give it positive V relatively to it's source (here at the mosfet's upper pin). If I reverse the V7 supply to -20V (this mosfet accepts +-20V at Gate) then I still have 7 Amps at the resistor. Not only it's behaviour is reversed, but it never shutoff ..., even with -30V , let's be fool, -50V relatively to Source, still 7 Amps...

by Henri47
July 31, 2020

but on this same Test2, when I run sweep DC, changing V7 from -20 to 20, expression I(R56.nA)-I(R56.nB) then I obtain a good looking behaviour, V7@ -20 the Amps are 14 Amps, and after V7 around -4V and up, it shortly falls to Zero A.

that's a total different behaviour from the simple DC solver....

by Henri47
July 31, 2020

V7@ 20V : Mosfet should be shut, high positif voltage on gate, but 30 AMP flow https://imgur.com/blmgopo

V7 @ -50V : Mosfet should be totalle open, high negative voltage on gate, but have only 7 Amps !! https://imgur.com/aJt77BF

You don't have these readings on your computer ?

by Henri47
July 31, 2020

[1] On ESSAIbuilDUP

Thanks for prompt arrival of progressing circuit.

The DC Solver is unable to find a solution, so the readings on ammeters and voltmeter cannot be trusted.

I will try and find some more CL time next week, to pull out a simplified path between the 48v, 36v and 24v supplies (for example, including mosfets, diodes and meters). This seems to be the critical area where there is newly built up circuitry.

[2] On Test2

When I apply 20v to V7 (that is, about +20v gate positive wrt drain) the current in the ammeters is 30.00fA (the same on the imgur clip). Look out for the tiny letter "f" = femto = 10^-15, not very much at all!

Sadly, for this interesting topic, there are now too many threads for me to follow and I cannot undertake to answer any more.

by EF82
July 31, 2020

EF82 thanks a lot for showing me this f "femto" ! I would never find it myself ! This changes a lot of things, really.

but mystery is still total with this : this is not femto ! https://imgur.com/a/1PNNbP6 and for [1] On ESSAIbuilDUP , on my side it does declare found a solution, and yes it's again a "femto trick" everywhere it's the femto trick. excepted here, don't see any little f

So I will start again, I gain a big hope now, promise, I'll track the femtos & some little hidden stuff !!

by Henri47
July 31, 2020

I have been looking again at ESSAIbuilDUP. I discovered that V6 and V5 (both 36v) are connected in parallel. As soon as I removed V5 the DC Solver started to work and all the meters updated.

A suggestion for simplification of the circuit layout. The wire from V9+ goes in a big loop, eventually crossing over itself without a connection - very confusing for humans (but probably OK for CL?).

by EF82
August 03, 2020

You mean V11 & V5 . yes that's true !

I already went more a lot forward since... to the point simulation was very very slow, 20 seconds... but did it. And after that I had to make it even more complex, then happen something very strange : a simple add-on circuit would have very obvious false readings (and no femto-trick !) . I copied the simple circuit alone and it worked well with good simulation. Put it back with the big one, even totally independant with it's own supply as per the former building, it did accept simulate, but fake reasult. Then was obliged to continue further like this : build small part alone and simulate it, then assemble with the big circuit...

then I've been to a point no simulation was possible at all because component do not exit in circuitLab... so free style.. hope no big mistakes in the circuit !!

by the way, thank you very much for your great help EF82 !

by Henri47
August 03, 2020

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