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Wiring Diagrams
Connection references for common domestic switching circuits and MK Electric Logic Plus accessories. For full technical datasheets, contact our counter team.
1-Way Switching
A single switch controls one or more lights. The switch interrupts the live conductor only — neutral runs directly to the lamp.
| Wire | From | To |
|---|---|---|
| Brown (Live) | Consumer unit | Switch terminal L |
| Brown (Switched live) | Switch terminal L1 | Lamp live terminal |
| Blue (Neutral) | Consumer unit | Lamp neutral terminal |
| Green/Yellow (Earth) | Consumer unit | Switch earth / lamp earth |
MK Part Numbers
2-Way Switching
Two switches control one light — typical staircase or landing circuit. Uses 3-core + earth cable between the two switches.
| Wire | From | To |
|---|---|---|
| Brown (Live) | Consumer unit | Switch 1 COM terminal |
| Brown / Black (Strappers) | Switch 1 L1 & L2 | Switch 2 L1 & L2 |
| Grey (Switched live) | Switch 2 COM terminal | Lamp live terminal |
| Blue (Neutral) | Consumer unit | Lamp neutral terminal |
MK Part Numbers
Intermediate Switching
Three or more switches control one light. An intermediate switch is wired between two standard 2-way switches, crossing or straight-connecting the strapper pair.
| Wire | From | To |
|---|---|---|
| Brown (Live) | Consumer unit | Switch 1 COM |
| Strappers A & B | Switch 1 L1 & L2 | Intermediate switch L1 & L2 |
| Strappers C & D | Intermediate switch L3 & L4 | Switch 2 L1 & L2 |
| Grey (Switched live) | Switch 2 COM | Lamp live terminal |
MK Part Numbers
Fan Isolator — Without Overrun Timer
A 2-pole connection for fans that run only while switched on. The isolator breaks both live and neutral for safe local isolation.
| Wire | From | To |
|---|---|---|
| Brown (Switched live) | Light switch | Isolator terminal L1 |
| Blue (Neutral) | Consumer unit | Isolator terminal N |
| Brown (to fan) | Isolator terminal L1 out | Fan live terminal |
| Blue (to fan) | Isolator terminal N out | Fan neutral terminal |
MK Part Numbers
Fan Isolator — With Overrun Timer
A 3-pole connection for fans with a built-in overrun timer. L2 provides a permanent live to keep the timer powered after the light switch opens.
| Wire | From | To |
|---|---|---|
| Brown (Switched live) | Light switch | Isolator terminal L1 |
| Brown (Permanent live) | Consumer unit (unswitched) | Isolator terminal L2 |
| Blue (Neutral) | Consumer unit | Isolator terminal N |
| 3 cores to fan | Isolator L1, L2, N out | Fan L (switched), L (timer), N |
MK Part Numbers
Steel backbox selection
Choose the correct flush box depth based on accessory type and cable size.
| Part Code | Depth | Gang | Typical Use |
|---|---|---|---|
| 3995 ZIC | 16mm | 1-gang | Plaster-depth flush box — shallow accessories only |
| 861 ZIC | 25mm | 1-gang | Standard domestic sockets and switches (2.5mm² cable) |
| 862 ZIC | 25mm | 2-gang | Standard 2-gang sockets and switches |
| 866 ZIC | 35mm | 1-gang | FCUs, some dimmers, larger accessories |
| 886 ZIC | 35mm | 2-gang | Cooker/shower switches with 6mm² supply cable |
| 877 ZIC | 47mm | 1-gang | Isolated shaver units (K701/K706) — transformer depth |
| 878 ZIC | 47mm | 2-gang | Cooker/shower switches with 10mm² supply cable |
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