## Tuesday, October 11, 2016

### HP Prime and TI-84 Plus CE: Conversion between Delta and Y Networks

HP Prime and TI-84 Plus CE:  Conversion between Delta and Y Networks

DELTA2Y:  Convert resistance from a Delta (Δ) network to Y network using Kirchhoff’s Law.

Y2DELTA:  Convert resistance from a Y network to Delta (Δ) network using Kirchhoff’s Law.

Variables

 Variable HP Prime TI-84 Plus CE R1 r1 X R2 r2 Y R3 r3 Z Ra ra A Rb rb B Rc rc C

DELTA to Y Networks

HP Prime Program:  DELTA2Y

EXPORT DELTA2Y(r1,r2,r3)
BEGIN
// Δ → Y Network
// 2016-10-10 EWS
LOCAL ra,rb,rc,w;
w:=r1+r2+r3;
ra:=(r1*r3)/w;
rb:=(r1*r2)/w;
rc:=(r2*r3)/w;
RETURN {ra,rb,rc};
END;

TI-84 Plus CE Program:  DELTA2Y

Input "R1=",X
Input "R2=",Y
Input "R3=",Z
X+Y+Z→W
X*Z/W→A
X*Y/W→B
Y*Z/W→C
Disp "RA=",A
Disp "RB=",B
Disp "RC=",C

Example:

Input:
R1 = 5 Ω
R2 = 3 Ω
R3 = 5 Ω

Results:
Ra = 1.923076923 Ω
Rb = 1.153846154 Ω
Rc = 1.153846154 Ω

Y to DELTA Networks

HP Prime Program:  Y2DELTA

EXPORT Y2DELTA(ra,rb,rc)
BEGIN
// Δ → Y Network
// 2016-10-10 EWS
LOCAL r1,r2,r3,w;
w:=ra*rb+rb*rc+ra*rc;
r1:=w/rc;
r2:=w/ra;
r3:=w/rb;
RETURN {r1,r2,r3};
END;

TI-84 Plus CE Program:  Y2DELTA

Input "RA=",A
Input "RB=",B
Input "RC=",C
AB+BC+AC→W
W/C→X
W/A→Y
W/B→Z
Disp "R1=",X
Disp "R2=",Y
Disp "R3=",Z

Example

Input:
Ra = 4 Ω
Rb = 8 Ω
Rc = 6 Ω

Results:
R1 = 17.33333333 Ω
R2 = 26 Ω
R3 = 13 Ω

Source:  Milton Gussow “Schaum’s Easy Outlines:  Basic Electricity”  McGraw Hill: New York 2012.

This blog is property of Edward Shore, 2016.