Energy 01
Smart Energy Meter Measure voltage, current, power, energy and estimated cost on an isolated low-voltage AC trainer.
LEVEL IntermediateBUDGET ₹1,850TIME 2 weeks
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
ISOLATED AC-L ── F1 ── LOAD ─────────────┐
│ │
PT1 CT1
│ │
U1 V-SENSE U2 I-SENSE
└── ADC1 ADC2 ──┘
U3 ESP32
I²C ───┤├── Wi-Fi
DS1 OLED
ISOLATED AC-N ───────────────────────────── Use only an isolation transformer or approved metering trainer for calibration.
NUMBERED BILL OF MATERIALS 9 total items
No. Ref. Component Specification Qty.
01 F1Cartridge fuse + holder 1 A, 250 V training circuit 1
02 PT1Isolated voltage transformer 230/6 V or approved AC sensor module 1
03 CT1Split-core current transformer 5 A/5 mA with burden resistor 1
04 U1Voltage signal conditioner isolated, 0–3.3 V output 1
05 U2Current signal conditioner precision rectifier / ADC interface 1
06 U3ESP32 development board dual ADC, Wi-Fi 1
07 DS1OLED display 0.96 in, I²C, 128×64 1
08 PS1Isolated DC supply 230 V AC to 5 V DC, enclosed 1
09 TB1Touch-safe terminal block 4-way, 250 V 1
Print / save project sheet as PDF SAFETY Calibrate only on an isolated trainer; do not prototype directly on mains.
Energy 02
Automatic Power Factor Correction Sense load power factor and switch staged capacitors to improve the displacement power factor.
LEVEL AdvancedBUDGET ₹3,800TIME 3 weeks
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
AC-L ─ F1 ─ CT1 ─────────────── LOAD
│ │
PT1 I-SENSE ─┐
└── V-SENSE ─────┴── U1 MCU ──┬─ Q1 ─ K1 ─ C1
├─ Q2 ─ K2 ─ C2
└─ Q3 ─ K3 ─ C3
AC-N ───────────────────────────────────────────
C1/C2/C3 each fitted with discharge resistor Use fused training capacitors and verify discharge before touching any stage.
NUMBERED BILL OF MATERIALS 17 total items
No. Ref. Component Specification Qty.
01 F1Control fuse 1 A, 250 V 1
02 PT1Isolated voltage sensor zero-cross capable 1
03 CT1Current transformer 5 A/5 mA 1
04 U1Microcontroller board Arduino Nano or equivalent 1
05 Q1–Q3Opto-isolated relay drivers 12 V coil interface 3
06 K1–K3Capacitor contactors trainer-rated with interlock 3
07 C1–C3Power-factor capacitors 2, 4 and 8 µF trainer stages 3
08 R1–R3Discharge resistors rated for capacitor voltage 3
09 DS1LCD display 16×2 with I²C interface 1
Print / save project sheet as PDF SAFETY Use fused, discharge-resistor-equipped training capacitors under supervision.
Renewables 03
Solar Battery Charge Controller Build a PWM charge controller with battery-voltage display, reverse-current protection and load cut-off.
LEVEL IntermediateBUDGET ₹2,400TIME 2 weeks
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
PV+ ─ F1 ─ D1 ─ Q1 PWM ─ L1 ───── BAT+
│ │
└─ D2 ──┴─ C1
PV− ───────────────────────────────── BAT−
PV divider ─┐ Battery divider ─┐
└──── U1 MCU ───────────┤
└─ Q2 ─ F2 ─ LOAD Begin with a current-limited bench supply before connecting the panel and battery.
NUMBERED BILL OF MATERIALS 10 total items
No. Ref. Component Specification Qty.
01 PV1Solar panel 18 V, 20–40 W 1
02 F1PV input fuse 3 A DC 1
03 D1Reverse-current diode Schottky, 5 A 1
04 Q1Power MOSFET logic-level, ≥40 V, heat-sinked 1
05 L1Buck inductor 100–220 µH, ≥4 A 1
06 D2Freewheel diode Schottky, ≥5 A 1
07 U1Microcontroller Arduino Nano or equivalent 1
08 Q2Load disconnect MOSFET logic-level, ≥20 A 1
09 BAT1Training battery 12 V, 7 Ah sealed battery 1
10 DS1Voltage/current display I²C OLED 1
Print / save project sheet as PDF SAFETY Use a current-limited source during testing and fit a battery-side fuse.
Safety 04
Transformer Temperature Protection Monitor winding or enclosure temperature and operate warning, fan and trip outputs at set thresholds.
LEVEL BeginnerBUDGET ₹1,200TIME 1 week
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
T1 surface ─ TH1 temperature sensor ─ U1 controller
├─ Q1 ─ K1 ─ FAN
├─ Q2 ─ BZ1 ALARM
└─ Q3 ─ K2 TRIP
12 V DC ─ F1 ────────────────────────────────┘ Fix the sensor to the transformer body with insulated thermal tape; do not access live windings.
NUMBERED BILL OF MATERIALS 11 total items
No. Ref. Component Specification Qty.
01 T1Low-voltage transformer model 230/12 V, guarded terminals 1
02 TH1Temperature sensor PT100 with MAX31865 or DS18B20 1
03 U1Controller board Arduino Nano 1
04 Q1–Q3Transistor relay drivers with flyback diodes 3
05 K1Fan relay 12 V coil, 5 A contacts 1
06 K2Trip relay 12 V coil, changeover 1
07 FAN1Cooling fan 12 V DC, 80 mm 1
08 BZ1Alarm buzzer 12 V DC 1
09 DS1Display 16×2 LCD 1
Print / save project sheet as PDF SAFETY Use a low-voltage model transformer; never expose live primary terminals.
Machines 05
Star-Delta Starter Training Panel Demonstrate timed star-delta starting with electrical interlocking, overload protection and status lamps.
LEVEL AdvancedBUDGET ₹5,500TIME 3 weeks
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
POWER: L1/L2/L3 ─ QF1 ─ K1 MAIN ─ OL1 ─ MOTOR U1/V1/W1
├─ K2 STAR → U2+V2+W2
└─ K3 DELTA → cross links
CONTROL: L ─ STOP(NC) ─ OL1(NC) ─ START(NO) ─ K1
K1 seal ─ KT1 timer ─┬─ KT1(NC)─K3(NC)─K2
└─ KT1(NO)─K2(NC)─K3 Electrical and mechanical interlocking between star and delta contactors is mandatory.
NUMBERED BILL OF MATERIALS 12 total items
No. Ref. Component Specification Qty.
01 QF1Three-pole MCB trainer rating, C curve 1
02 K1Main contactor 3-pole, 12/24 V coil 1
03 K2Star contactor 3-pole with NC interlock 1
04 K3Delta contactor 3-pole with NC interlock 1
05 KT1On-delay timer 0–30 s, changeover contacts 1
06 OL1Thermal overload relay matched to motor current 1
07 S0/S1Stop / start push buttons 1 NC + 1 NO 2
08 H1–H3Status lamps control-voltage rated 3
09 M1Six-terminal induction motor protected laboratory trainer 1
Print / save project sheet as PDF SAFETY Commission on a protected low-voltage trainer before any supervised motor test.
Machines 06
DC Motor PWM Speed Controller Control speed and direction of a low-voltage DC motor and display duty cycle and measured speed.
LEVEL IntermediateBUDGET ₹1,600TIME 2 weeks
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
12 V+ ─ F1 ───────────────┬──────────────┐
Q1(high) Q3(high)
├──── M1 ─────┤
Q2(low) Q4(low)
12 V− ──────────────────────┴────────────┴──
U1 MCU ─ gate driver ─ Q1..Q4 H1 speed sensor ─ U1 Add gate dead-time and guard the shaft, coupling and sensor magnet.
NUMBERED BILL OF MATERIALS 15 total items
No. Ref. Component Specification Qty.
01 F1DC fuse 5 A blade fuse 1
02 U1Microcontroller Arduino Nano 1
03 U2H-bridge gate driver dead-time capable 1
04 Q1–Q4N-channel MOSFETs logic-level, ≥30 V, heat-sinked 4
05 D1–D4Flyback diodes fast recovery, ≥5 A 4
06 M1Permanent-magnet DC motor 12 V, ≤3 A 1
07 H1Hall speed sensor digital output with magnet 1
08 RV1Speed potentiometer 10 kΩ linear 1
09 DS1RPM display OLED, I²C 1
Print / save project sheet as PDF SAFETY Add flyback protection, a fuse and a guarded coupling.
Automation 07
Automatic Water-Level Controller Start and stop a pump model from tank levels with dry-run protection and manual/automatic modes.
LEVEL BeginnerBUDGET ₹1,100TIME 1 week
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
TANK: COM ─ LOW(P1) ─ HIGH(P2) SUMP: DRY(P3)
│ │ │ │
└── isolated probe interface U1 ───┘
│
12 V ─ F1 ─────────────── U2 controller ─ Q1 ─ K1 ─ PUMP
└─ AUTO / MANUAL selector Keep the controller above the water line and use only a separated extra-low-voltage pump.
NUMBERED BILL OF MATERIALS 13 total items
No. Ref. Component Specification Qty.
01 P1–P3Level probes / float switches stainless steel, low-voltage sensing 3
02 U1Probe interface AC excitation or opto-isolated 1
03 U2Controller Arduino Nano or relay logic 1
04 Q1Relay driver transistor with flyback diode 1
05 K1Pump relay 12 V coil, 10 A contacts 1
06 PUMP1Demonstration pump 12 V DC submersible 1
07 S1Auto/manual selector 2-position maintained 1
08 H1–H3Level/status LEDs 5 mm with resistors 3
09 F1Pump fuse 3 A DC 1
Print / save project sheet as PDF SAFETY Use an isolated 12 V pump model and keep control electronics dry.
Safety 08
Three-Phase Sequence and Failure Alarm Identify correct phase sequence and signal phase loss or reversal using an isolated sensing front end.
LEVEL AdvancedBUDGET ₹2,900TIME 3 weeks
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
R ─ F1 ─ ISO1 ─ pulse R ─┐
Y ─ F2 ─ ISO2 ─ pulse Y ─┼─ U1 phase logic ─ K1 healthy
B ─ F3 ─ ISO3 ─ pulse B ─┘ └─ BZ1 fault
U1 checks R→Y→B order, missing pulse and voltage window Test only on a purpose-built three-phase trainer with instructor supervision.
NUMBERED BILL OF MATERIALS 15 total items
No. Ref. Component Specification Qty.
01 F1–F3Phase sensing fuses 100 mA, 500 V 3
02 ISO1–ISO3Isolated phase detectors opto-isolated zero-cross modules 3
03 U1Phase-sequence controller microcontroller or dedicated IC 1
04 K1Healthy output relay 12 V coil, changeover 1
05 BZ1Fault buzzer 12 V DC 1
06 H1–H4Phase/fault indicators R/Y/B LEDs plus fault lamp 4
07 PS1Isolated control supply 12 V DC enclosed 1
08 TB1Touch-safe phase terminals 4-pole R-Y-B-N 1
Print / save project sheet as PDF SAFETY Develop with a three-phase trainer; final testing requires instructor supervision.
Automation 09
Automatic Street-Light Controller Control dimmed and full-brightness LED lighting using ambient light and motion detection.
LEVEL BeginnerBUDGET ₹950TIME 1 week
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
12 V+ ─ F1 ─ LED1 string ─ Q1 MOSFET ─ 0 V
gate ← PWM ← U1 MCU
LDR1 + R1 divider ─ ADC ─┤
PIR1 motion output ──────┤
S1 mode switch ──────────┘ Use a heat sink for the LED and MOSFET and keep the demonstrator at SELV voltage.
NUMBERED BILL OF MATERIALS 8 total items
No. Ref. Component Specification Qty.
01 U1Microcontroller Arduino Nano 1
02 LDR1Light sensor LDR with 10 kΩ divider 1
03 PIR1Motion sensor HC-SR501 or equivalent 1
04 Q1LED power MOSFET logic-level, ≥30 V 1
05 LED1Street-light model 12 V LED module, 10 W max 1
06 F1DC fuse 2 A 1
07 S1Mode selector auto/off/manual 1
08 PS1DC power supply 12 V, 2 A, current-limited 1
Print / save project sheet as PDF SAFETY Keep the demonstrator at SELV voltage and protect the supply against short circuits.
Safety 10
Domestic Distribution-Board Trainer Create a labeled single-phase training board showing isolation, RCCB, MCB circuits, neutral and PE bars.
LEVEL IntermediateBUDGET ₹4,500TIME 3 weeks
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
ISOLATED L ─ Q0 DP ─ RCCB1 ─┬─ MCB1 ─ S1 ─ LAMP
├─ MCB2 ─ SOCKET
└─ MCB3 ─ FAN MODEL
ISOLATED N ─────────────────────── N-BAR ─ returns
PE ─────────────────────────────── PE-BAR ─ exposed metal
TEST: L after MCB ─ RTEST ─ S2 ─ N before RCCB Faculty approval and an isolated training supply are required before energizing.
NUMBERED BILL OF MATERIALS 11 total items
No. Ref. Component Specification Qty.
01 Q0Double-pole isolator 16 A trainer unit 1
02 RCCB1Residual-current device 2-pole, 30 mA 1
03 MCB1–MCB3Miniature circuit breakers 6 A, B curve 3
04 N-BARNeutral busbar insulated enclosure type 1
05 PE-BARProtective-earth bar brass, bonded to panel 1
06 S1Lamp switch 6 A, one-way 1
07 SK1Training socket shuttered, labeled 1
08 RTEST/S2RCCB test network supervisor-selected resistor + push button 1
09 T1Isolation transformer 230/230 V, current-limited trainer 1
Print / save project sheet as PDF SAFETY Use a purpose-built isolated training supply and faculty approval before energizing.
Automation 11
IoT Motor Condition Monitor Log motor vibration, temperature and current and display warning trends on a local dashboard.
LEVEL IntermediateBUDGET ₹2,700TIME 2 weeks
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
MOTOR TRAINER ─ CT1 current ─ ADC1 ─┐
TH1 temperature ─ 1-Wire ─┤
ACC1 vibration ─ I²C ─────┼─ U1 ESP32 ─ Wi-Fi ─ dashboard
└─ H1 warning + BZ1 alarm
5 V isolated supply ─ F1 ──────────────┘ Isolate the motor before mounting sensors and refit all rotating-part guards.
NUMBERED BILL OF MATERIALS 9 total items
No. Ref. Component Specification Qty.
01 U1ESP32 development board Wi-Fi, dual-core 1
02 CT1Current sensor isolated CT or Hall module 1
03 TH1Temperature sensor DS18B20 probe 1
04 ACC1Accelerometer ADXL345, 3-axis 1
05 U2Signal conditioner CT burden, bias and filter 1
06 DS1Local display 0.96 in OLED 1
07 BZ1Alarm buzzer 5 V active 1
08 PS1Isolated supply 5 V, 2 A 1
09 ENC1Sensor enclosure non-metallic, cable glands 1
Print / save project sheet as PDF SAFETY Mount sensors with the machine isolated and guard all rotating parts.
Renewables 12
Portable Solar Study Lamp Design an efficient rechargeable LED lamp with charge indication, low-battery cut-off and enclosure.
LEVEL BeginnerBUDGET ₹1,350TIME 1 week
Open circuit diagram & full component list + CIRCUIT / CONNECTION DIAGRAM Training design · verify ratings before assembly
PV1 ─ F1 ─ U1 solar charger ─ BAT1 LiFePO₄
│
└─ U2 protection ─ S1 ─ U3 LED driver ─ LED1
LDR1 ─ auto-enable ───────────────┘
U1 status outputs ─ CHARGE / FULL indicators Use only protected LiFePO₄ cells and provide ventilation around the LED heat sink.
NUMBERED BILL OF MATERIALS 9 total items
No. Ref. Component Specification Qty.
01 PV1Solar panel 6 V, 5–10 W 1
02 F1PV fuse 1.5 A resettable 1
03 U1Solar charge controller LiFePO₄-compatible 1
04 BAT1Protected battery cell LiFePO₄ 3.2 V, 3–6 Ah 1
05 U2Battery protection board overcharge, over-discharge, short circuit 1
06 U3Constant-current LED driver 350–700 mA 1
07 LED1High-efficiency LED 3 W on heat sink 1
08 LDR1Ambient-light sensor LDR divider module 1
09 S1Brightness selector off/low/high 1
Print / save project sheet as PDF SAFETY Use protected cells and verify polarity before assembly.