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(11C) Generate Pair of Parallel Resistors - Printable Version

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(11C) Generate Pair of Parallel Resistors - Gamo - 10-26-2018 11:47 AM

Program to generate in endless loop of
Two Parallel Resistors with your desire total.

This program give different pair of resistors that match the giving total.

Procedure:

[A] // Total [ENTER] Step [A]

[B] // Press any key to Stop Loop [B] 1st Resistor [R/S] 2nd Resistor [R/S] continue forward loop.

[C] // [C] Backward loop, Press any key to Stop Loop [B] 1st Resistor [R/S] 2nd Resistor.

[E] Initialize

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

Example: FIX 3

Destination total is 25.75
Pick two difference pair of resistors of your choice.

I will use 0.5 for loop steps.

[E] Initialize

25.75 ENTER .5

[A] ---->Program keep generate two resistors that match your giving total in this case is 25.75

Once you see the pair you like press any key to stop I recommend ENTER key.

[B] I pick this pair: 30.25 [R/S] 173.097 [R/S] --> Continue Loop Forward

[C] This loop go backward: Once you see the pair you like press any key to stop.
I pick this pair: --> [B] 28.250 [R/S] 290.975

---------------------------------------------------------
Program:
Code:

LBL A
STO 1
Rv
STO 0
RCL 0
LBL 5
RCL 1
+
LBL 1
STO 2
PSE
RCL 0
x
RCL 2
RCL 0
-
÷
STO 3
PSE
PSE
LBL 3
RCL 4
X≠0
GTO 4
RCL 2
GTO 5
------------------------------
LBL B
RCL 2
R/S
RCL 3
R/S
GTO 3
----------------------------
LBL C
1
STO 4
LBL 4
RCL 2
RCL 1
-
GTO 1
---------------------------
LBL E
CLx
STO 1
STO 2
STO 3
STO 4
RTN

Gamo


RE: (11C) Generate Pair of Parallel Resistors - Gamo - 10-27-2018 06:00 AM

Program use for total up even numbers of the "Same Resistors Value" in Parallel.

Procedure:

Resistor Value [ENTER] even number of resistors [A]

Example:

What is the total of 3 pair of 15 ohm Restistors in Parallel?

15 ENTER 6 [A]

Answer: 2.5 ohm

-----------------------------------------------------------------
Program:
Code:

LBL A
STO 7
Rv
1/x
STO 1
----------------------------
LBL 1
STO 2
1/x
STO 5
1
STO+6
RCL 6
RCL 7
X=Y
GTO 2
RCL 1
RCL 2
+
GTO 1
----------------------------
LBL 2
0
STO 6
RCL 5
RTN

Gamo


RE: (11C) Generate Pair of Parallel Resistors - Thomas Klemm - 10-27-2018 10:51 AM

(10-27-2018 06:00 AM)Gamo Wrote:  What is the total of 3 pair of 15 ohm Restistors in Parallel?

15 ENTER 6 [A]

Answer: 2.5 ohm

You can improve that program a bit:
Code:
LBL A
÷
RTN

Or then just use the dedicated key: [÷]

Kind regards
Thomas


BTW: Your program doesn't work properly unless the register 6 is initialised to 0.
It doesn't help that you are doing it at the end of the program.


RE: (11C) Generate Pair of Parallel Resistors - Dieter - 10-29-2018 05:28 PM

(10-26-2018 11:47 AM)Gamo Wrote:  Program to generate in endless loop of
Two Parallel Resistors with your desire total.
This program give different pair of resistors that match the giving total.

Gamo, after looking at this program for a few days I still do not understand where it may be usedful. Could you describe a practical application?

(10-26-2018 11:47 AM)Gamo Wrote:  Destination total is 25.75
Pick two difference pair of resistors of your choice.
...
I pick this pair: 30.25 [R/S] 173.097
...

OK. You now know that 25,75 Ω equals 30,25 Ω and 173,097 Ω in parallel.
But where do you get such resistors from?!

What about a different program: store the resistors that you have in R1, R2, R3, ... and let the program calculate the combinations that come close to a certain target resistance.

Dieter