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#1 Jan 10, 2017
Atousa
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Encountering with loop error in PSpice

Hi
I encountered with following error in simulating the circuit shown below in PSpice. 

ERROR -- Voltage source and/or inductor loop involving E_U2
You may break the loop by adding a series resistance

Could any one help me please?

http://uupload.ir/files/8xbv_opamp1.png

Tue, 2017-01-10 03:23
RobertoGb
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Hello,

This error is related to bias point calculation. When the simulator has DC nodes isolated from ground, this error can pop up. The solution is to place very small resistors in serie (10m for example). In your case, you need to place resistors at the output of U2, U4 and U5 and after V3.

I hope it helps.

 

 

Tue, 2017-01-10 03:56 (Reply to #2)
Atousa
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Thanks for your concern.

i did what you said but the problem still remains :(

http://uupload.ir/view/dggk_opamp1.png

 

Tue, 2017-01-10 04:04 (Reply to #3)
Atousa
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the problem resists :|

http://uupload.ir/files/8yzm_opamp1.png

ERROR -- Voltage source and/or inductor loop involving E_U2
You may break the loop by adding a series resistance

Tue, 2017-01-10 04:32
RobertoGb
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You also need to place a resistor after V5. It should work. Let me know

Tue, 2017-01-10 05:20 (Reply to #5)
Atousa
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Thanks but:

ERROR -- Voltage source and/or inductor loop involving E_U4
You may break the loop by adding a series resistance

http://uupload.ir/files/k50b_untitled.png

:(

Tue, 2017-01-10 05:25
RobertoGb
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Well, then it could be that the resistors are not well connected. It is working at my end. Could you send me the design to pspice@flowcad.de so that I can debug the problem?

Thanks

Tue, 2017-01-10 05:28 (Reply to #7)
Atousa
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Of couse! I'm so grateful

Wed, 2017-01-11 03:51 (Reply to #8)
Atousa
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Dear Roberto,
Thank you so much for your time and help. My problem was solved and it is working now. :) 

Best regards

Atousa

Fri, 2017-01-20 03:32 (Reply to #9)
Atousa
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Dear Roberto,

I have another problem with my circuit.

I would be really grateful if you could tell me why two of these voltage generators (V1 and V2) show negative values whereas the specified values for all of them via text files are positive.

Regards

Atousa

http://uupload.ir/filelink/Qd1ZhCoodloW/qx10_schematic1_page1.pdf

http://uupload.ir/files/xar6_output.png

 

Thu, 2023-03-30 03:32
emmausa
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One way to resolve this issue is to break the loop by adding a series of

incredibox resistance to the loop. You can do this by placing a resistor in series with the voltage source or inductor that is involved in the loop. The value of the resistor should be small enough to not significantly affect the circuit's behavior, but large enough to break the loop.

Mon, 2023-04-24 08:54
modulerf
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it work, thank you for information.

 

 

------------------

433Mhz RF Radio Module Receiver RXB10

Thu, 2023-05-04 03:05
jendy
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The error message you 

melon playground are receiving in PSpice indicates that there is a voltage source or inductor loop in your circuit that involves the element named E_U2. This loop can cause convergence issues in the simulation and needs to be addressed.

Thu, 2023-06-22 00:46
karausa
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I like how thoroughly you cover the facts about this subject. I'm grateful for it and I hope you carry retro bowl on the wonderful work.

Wed, 2023-08-02 22:48
cubero
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Ensure that the inductor model 

pizza tower and its parameters are correctly defined. 

poppy playtime chapter 3 A faulty model or incorrect parameters can sometimes cause convergence issues in simulations.

Sun, 2023-08-06 22:14
lopez
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To break the loop, slope game you can add a small series resistance (e.g., a few ohms) in one of the components involved in the loop.

Wed, 2023-09-06 22:54
andree23
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You need identify the nodes in your circuit that are isolated from travle ground and are causing convergence problems. These nodes are typically found in components like voltage sources (U2, U4, U5) and voltage dividers (V3) where there's no direct path to ground.

Tue, 2023-10-24 17:44
rhysfaulkner
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You need identify the nodes in your circuit that are isolated from posterdle ground and are causing convergence problems. These nodes are typically found in components like voltage sources (U2, U4, U5) and voltage dividers (V3) where there's no direct path to ground on uvdown

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