3 Phase Line to Single Phase Wiring
Learn 3-phase line wiring installation for a single-phase supply in a house using a 3-phase meter with step-by-step wiring, safety tips, and an accurate setup guide.

power socket wiring
In a 3-pin power socket wiring diagram, you can find a proper way of Live, Neutral, and Earth connections that will guarantee a safe and uninterrupted power supply. The live is usually connected to the right terminal (brown), the neutral to the left terminal (blue), and the earth to the top terminal (green/yellow), and is commonly used in UK-style BS 1363 sockets. Adequate wiring also has proper polarity, protection against grounding, and a low drop in voltage. Cables should always be sheathed well, stripped off without any bare copper, and fitted securely into terminals by means of a multimeter or socket tester as a test. The majority of present-day installations are in UK colour codes introduced after 2004. The circuit has in-built shutters and faceplate earth bridging that increase the protection of the user.
3 Phase Line to Single Phase Wiring Formula & Summary:
Voltage (V): 230V single phase from 3 phase supply
Current (I): Depends on household load
Power (P):P = V × I × Power Factor
Wiring Connections: Phase (L1) → 3 Phase Meter input → Output to house load
Neutral → Meter neutral input → Output to house neutral
Earth connected to house grounding system
3-phase to single-phase wiring
The connection of a 3-phase line wiring system to feed a single-phase load in a house with a 3-phase meter adopts a cautious method of connecting one of the phases and the neutral line to the meter and finally to the load in and around the household. This arrangement is typical where the customer can get access to three-phase power, but only needs single-phase power to drive the residential load. The 3-phase uses a meter that reads the power usage of all three phases, whereas the house load wiring is only connected to one of the phases and the neutral line. Proper installation also allows the meter to report an accurate level of consumption, avoid electrical risks, as well as follow the regulations of safety. Wiring involves suitable identification of live, neutral, and earth conductors, well-connected wires, and even the circuit has suitable protection. The strategy is advantageous to the households as it will help benefit the monitoring of energy and will be cost-effective using the 3-phase supply already in place.
house single-phase connection
Terminal | Connection | Description |
---|---|---|
Phase Input (L1) | One phase line from a 3-phase supply | Supplies a single-phase load through a meter |
Phase Output | To house a single-phase load | Power output to house wiring |
Neutral Input | Neutral from supply | Completes circuit for single phase |
Neutral Output | To house the neutral line | Neutral return from load |
Earth | House grounding system | Safety grounding |
Frequently Asked Questions - 3 Phase Line to Single Phase Wiring:
Can I use a 3 phase meter for a single-phase house connection?
Yes, a 3 phase meter can monitor consumption on all phases while the house uses single-phase supply.
Which phase is used for single-phase wiring from 3 phase supply?
Typically, one phase line (L1) is selected to supply the single-phase house load.
Is neutral connection necessary in this wiring?
Yes, neutral is essential to complete the single-phase electrical circuit.
How do I ensure safety in 3 phase to single phase wiring?
Use proper grounding, circuit breakers, and follow electrical codes during installation.
Can this setup support high power appliances?
Yes, but ensure the wiring and meter ratings match the load requirements.
Does the 3 phase meter show consumption for single-phase loads?
Yes, it records consumption on all phases including the one supplying the house.
Can multiple houses share one 3 phase meter?
No, each house should have its own meter for accurate billing and safety.
What wire sizes are recommended for house wiring from 3 phase supply?
Typically, 2.5mm² for power and 1.5mm² for lighting circuits are used.
Is earth wire connection mandatory?
Yes, it is crucial for electrical safety and to prevent shocks.
What happens if I connect the wrong phase to the house wiring?
It can cause unbalanced load, potential damage, and inaccurate meter readings.