From wire To plc
how to check motor
check bobinage resistance all =
check bobinage avec carcase pour fuit
motor
Id(Demarage)= x3 to x6 In(nominal)
P=V x I x
worldstandards three-phase-electric-power/
Choosing componant
| Componant | How to choose it | when to use it |
|---|---|---|
| Power suply | V=V I=Itotal(i1+i2+i3+....) x 1.25 ou I(i1+i2+i3+....) + 25% important : u can choose higher Current rating but cannot choose higher voltage rating |
|
| Fuse | V=V I=I / 0.75 faster then mcb |
For sensitive equipement (plc,hmi,electronic) |
| Contactor | V =380/√3 220v coil rate and v Ac/Dc I>=Id |
Motor |
| MCCCB | bigger MCB I>1000Amp or someth Ir=(0.7 ,1) x In (adjustable) Tr (Adustable time of cut) most of the time they give u fixed value Like x 6Ir cut in 15sec and u will choose the second one like x 1.5Ir for like (400s - 100s) so the breaker trip between 400sec to 15sec It is used to protect the Cable between your electrical panel and the Power source , taking into account the total current consumption of the panel. |
main choose it depends on cable |
| Disjoncteur MCB | ||
| Disjoncteur moteur | adjustable Ir=In(-1,+1) | faster (more sensitive) used for motors |
| ELCB - RCCB differenciel | protection contre la fuite | |
| MCCB Cable | voltage drop % formula = (√3 x I x distance x 100 x cable impedence par ohm metre)/ (380v , 220v) this should be > 3% if not need bigger cable Exemple : (1.73 x 32 x 20 x 100 x 0.00789)/380 = 2.5%<3% its good, we got 0,00789 for 2.5mm cable for ( |
|
| Soft starter | smooth startup/shutdown |
|
| VFD | Same as Soft starter but with controlled frequency (speed) | |
Choosing start
| Feature | Direct-On-Line (DOL) | Star-Delta (Y-Δ) | Soft Starter | Variable Frequency Drive (VFD) |
|---|---|---|---|---|
| Primary Function | Full-voltage startup | Reduced-voltage startup | Smooth start/stop control | Full continuous speed & torque control |
| Typical Motor Size | Small (< 5.5 to 7.5 kW) | Medium (7.5 to 75 kW) | Medium to Large (> 7.5 kW) | Any size (0.12 kW to MWs) |
| Running Speed | 100% full speed | 100% full speed | 100% full speed | Variable (0% to 100%+) |
| Starting Current | Very High (5–8× nominal) | Reduced (≈ 33% of DOL) | Adjustable (2–4× nominal) | Low (1× nominal or less) |
| Starting Torque | High (100% full torque) | Low (≈ 33% of DOL torque) | Adjustable / Smooth ramp | Full torque available at 0 RPM |
| Mechanical Stress | High (sudden jerk) | Moderate (surge during transition) | Very Low (gradual acceleration) | None (completely smooth control) |
| Energy Savings | None | None | Minimal (reduces peak demand) | High (up to 50%+ on pumps/fans) |
| Relative Cost | Lowest ($) | Low to Moderate ($$) | Moderate to High ($$$) | Highest ($$$) |
Choosing cables
0.75mm for control circuit (plc,.....)
| Volts | kW | 1.5 mm² | 2.5 mm² | 4 mm² | 6 mm² | 10 mm² | 16 mm² | 25 mm² | 35 mm² | 50 mm² | 70 mm² | 95 mm² |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 400V | 0.37 | 810 | 1350 | 2160 | 3240 | 5500 | 8530 | — | — | — | — | — |
| 400V | 0.55 | 550 | 920 | 1480 | 2230 | 3780 | 5860 | 8890 | — | — | — | — |
| 400V | 0.75 | 410 | 680 | 1090 | 1640 | 2780 | 4330 | 6570 | 9010 | — | — | — |
| 400V | 1.1 | 300 | 500 | 810 | 1210 | 2060 | 3200 | 4850 | 6640 | 9220 | — | — |
| 400V | 1.5 | 220 | 370 | 590 | 880 | 1500 | 2340 | 3560 | 4890 | 6830 | 9230 | — |
| 400V | 2.2 | 150 | 250 | 400 | 600 | 1030 | 1600 | 2440 | 3350 | 4680 | 6340 | 7990 |
| 400V | 3 | 110 | 190 | 310 | 460 | 790 | 1230 | 1880 | 2590 | 3630 | 4930 | 6230 |
| 400V | 3.7 | 90 | 150 | 240 | 370 | 630 | 980 | 1490 | 2050 | 2870 | 3900 | 4920 |
| 400V | 4 | 80 | 140 | 230 | 340 | 590 | 920 | 1390 | 1910 | 2670 | 3600 | 4520 |
| 400V | 5.5 | — | 110 | 170 | 260 | 440 | 690 | 1060 | 1450 | 2030 | 2750 | 3460 |
| 400V | 7.5 | — | 80 | 130 | 200 | 340 | 530 | 810 | 1110 | 1560 | 2120 | 2680 |
| 400V | 11 | — | — | 90 | 130 | 230 | 360 | 550 | 750 | 1060 | 1440 | 1820 |
| 400V | 15 | — | — | — | 100 | 170 | 270 | 410 | 570 | 800 | 1080 | 1370 |
| 400V | 18.5 | — | — | — | 80 | 140 | 210 | 330 | 450 | 630 | 860 | 1090 |
| 400V | 22 | — | — | — | — | 120 | 180 | 280 | 380 | 540 | 740 | 930 |
| 400V | 30 | — | — | — | — | — | 130 | 210 | 280 | 400 | 540 | 680 |
| 400V | 37 | — | — | — | — | — | — | 170 | 230 | 320 | 440 | 550 |
| 400V | 45 | — | — | — | — | — | — | — | 180 | 270 | 360 | 460 |
Sensor
Detecteur : digital
capteur : analogic
Mecanic : fin de course
Proximity: Digital 12/24DC
inductive : metal
capasitive : used for everything no metal
Level sensors :
Digital :contact ,capacitive
Analog :
Ultra-sonic : send signal and get it back to mesure distance between sensor and object
Hydro-static : pressure
| Analog | Digital | |
|---|---|---|
| Solid | Ultrasonic | Capacitive |
| Liquid | Hydro-static | منخفض اللزوجة : fin course ou capacitive لزوجة عالية : use analogic |
Tempirature sensors :
| Type | range | speed | How it work | sensitivity | cost | Wire | |
|---|---|---|---|---|---|---|---|
| NTC | [-55c,+200c] | Fastest | resistance when temp+ resistance - | 1 | low | ||
| RTD (pt100,pt1000....) | Class A [-100c,+450c] Error:+/-0.35c Class B [-196c,+600c] Error :+/- 0.8c |
every 1 degree + 0.39ohm | Class A>Class B | 2 wire 3 wire 4 wire u need special module To read 4-20mA internel conversion |
|||
| Thermoo-Couple | Classes J,K,E,T ranges between [-250c,1250c] with diff errors |
mesure tempirature between 2 probes used for hight tempirature aplication |
Higher | ||||
Flow sensors : analogic
usually the sensor come mounted between 2 pipes
KG/sec ; Cubic/sec ; cm/sec ; m/sec usually can be changed from ecran
Ultra sonic : send light and calculate
Rotary disk : It rotage magnet to generate magnetic field +speed + voltage
Pressure sensors
presostat : digital
capteur de pression : analogic
Bar
load cell
weighing scale
they need analyser they dont produce signal
| sensitivity | ||
|---|---|---|
| Pneamatic | when there is weight air pressure change | 3 |
| Hydrolic | when there is weight oil pressure increase | 4 |
| Strain Gauge | Uses semiconductor or foil resistance grids (strain gauges) attached to a flexing metal body | 2 |
| Capacitive | when there is weight 2 sides of capacitor gets close so more capacity | 1 |
Troubleshooting
Power suply
No led : check fuse
Motor :
slow : check star or delta
Overload trip : check riglage if correct check star delta
VFD :
Digital sensor :
clean the head
Guide de Choix de Couplage et Démarrage des Moteurs Triphasés (Réseau 400 V)
Ce guide récapitule les règles d'association entre la plaque signalétique d'un moteur asynchrone triphasé et la tension du réseau électrique (400 V entre phases, standard en Algérie).
1. Tableau Récapitulatif Synthétique
| Plaque Signalétique | Tension du Réseau | Couplage Permanent | Démarrage Étoile-Triangle ( |
Méthodes de Démarrage Autorisées |
|---|---|---|---|---|
| 230 V / 400 V | 400 V Triphasé | Étoile ( |
❌ INTERDIT (Destruction du moteur) | • Direct en Étoile • Variateur de fréquence (VFD) • Démarreur progressif (Soft-Starter) |
| 400 V / 690 V | 400 V Triphasé | Triangle ( |
✅ AUTORISÉ | • Direct en Triangle • Étoile-Triangle ( • Variateur de fréquence / Démarreur progressif |
| 230 V / 400 V | 230 V Triphasé | Triangle ( |
✅ AUTORISÉ (uniquement sur réseau 230V tri) | • Direct en Triangle • Étoile-Triangle ( |
4. Comparatif des Solutions pour Réduire le Courant de Démarrage (sur Réseau 400 V)
| Type de Moteur | Démarrage |
Alternative Recommandée |
|---|---|---|
| 230 V / 400 V | ❌ Non | Démarreur progressif (Soft-starter) ou Variateur de fréquence (VFD) |
| 400 V / 690 V | ✅ Oui | Démarrage Étoile-Triangle, Démarreur progressif, ou Variateur |