Resistors in parallel

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Any number of resistors in parallel will give you a single effective resistance between points A and B.
You cannot determine the value of each individual resistor by measurement with any type of meter.

If you know the values of all but one resistor, you can calculate the unknown value using the parallel resistor equation.

Thank you all!
I also found some answers here that resolved my doubts.

 

Thank you all!
I also found some answers here that resolved my doubts.

To be certain, tell us in your own words what you have learned.

 

hi k89.
This is an LTS example for your circuit. Note the Plots. -5C to +40C, 36K down to 6k for the NTC.
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I am also trying to simulate the thermal model, but I encounter this error when setting the current (self heating) B1:

There is something about LTSpice that I need to change (I mean the syntax) but I am not very experienced with LTSpice.
Can you figure out the problem?

I attach the file @ericgibbs

 

hi k89,
I have attached my asc file, try it to make sure it runs OK on your pC, then we can modify the values to suit your NTC.
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Post your asc file for post #23

 

hi k89,
I have attached my asc file, try it to make sure it runs OK on your pC, then we can modify the values to suit your NTC.
E
Post your asc file for post #23
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I have just posted the file (edited my post #23).

I have problems not with your simulation (that I can do well), but just (see image and attached file in my #23 post) with setting the B1 current

 

hi k,
Checking the circuit in post #23, you appear to be trying to determine the resistance of R1 using values from the T_NTC equation that depend upon the values of R1, which in turn depend upon the values of T_NTC.

ie: two interdependent unknown values.

Please tell me what you are trying to show in your simulation and I will endeavour to help you.
Start off with a very basic circuit.
E

 

hi k,
Look at this simple example, T_NTC is the PWL value of V1.
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hi k,
Checking the circuit in post #23, you appear to be trying to determine the resistance of R1 using values from the T_NTC equation that depend upon the values of R1, which in turn depend upon the values of T_NTC.

ie: two interdependent unknown values.

Please tell me what you are trying to show in your simulation and I will endeavour to help you.
Start off with a very basic circuit.
E

hi k,
Checking the circuit in post #23, you appear to be trying to determine the resistance of R1 using values from the T_NTC equation that depend upon the values of R1, which in turn depend upon the values of T_NTC.

ie: two interdependent unknown values.

Please tell me what you are trying to show in your simulation and I will endeavour to help you.
Start off with a very basic circuit.
E

Thank you first of all for your reply!
I just opened another thread here because my problem doesn't fit with the thread "Measure resistor with a Multimeter" opened by @andrew74