Wednesday, April 26, 2017

HP Prime and TI-84 Plus: Basic Wheatstone Full Bridge Circuit

HP Prime and TI-84 Plus:  Basic Wheatstone Full Bridge Circuit

The program WHEATSTONE (HP Prime) and WHTSTONE (TI-84 Plus CE) deals with the full Wheatstone circuit:



Formulas

EA = E * (1 – R4/(R4 + R3))
EB = E * (1 – R1/(R1 + R2))
eO = EA – EB

Variables used:  A = R1, B = R2, C = R3, D = R4, L = EA, R = EB, O = eO

Resistance is measured in ohms (Ω), current in volts (V).

HP Prime Program WHEATSTONE

EXPORT WHEATSTONE()
BEGIN
// 2017-04-25 EWS

LOCAL K,A,B,C,D,L,R,O;

INPUT({A,B,C,D,E},
"Basic Wheatstone",
{"R1: ","R2: ","R3: ","R4: ",
"E: "});
L:=E*(1-D/(D+C));
R:=E*(1-A/(A+B));
O:=L-R;
PRINT();
PRINT("EA: "+L);
PRINT("EB: "+R);
PRINT("e0: "+O);
END;

TI 84 Plus CE Program WHTSTONE

"2017-04-25 EWS"
Input "R1: ",A
Input "R2: ",B
Input "R3: ",C
Input "R4: ",D
Input "E: ",E
E*(1-D/(D+C))→L
E*(1-A/(A+B))→R
L-R→O
Disp "EA: ",L
Disp "EB: ",R
Disp "EO: ",O

Example

Inputs:  R1:  200 Ω, R2:  150 Ω, R3:  180 Ω, R4:  200 Ω, E:  16 V

Results:   EA ≈ 7.57895 V, EB ≈ 6.85714 V, eo ≈ 0.742180 V

Source:

Strain Gages and Instruments.  Tech Note TN-514  Vishay Precision Group.  February 1, 2013.  Link:  http://www.vishaypg.com/docs/11064/tn514.pdfhttp://www.vishaypg.com/docs/11064/tn514.pdf

Note:

I will be taking some time off from blogging in early May. I am going to work on a presentation that I hope to present in HHC 2017 this September (link: http://hhuc.us/2017/ ).  I encourage anyone to come attend the HHC conferences, they are a lot of fun.  This year the conference will be in Nashville.

Eddie

This blog is property of Edward Shore, 2017