FAQ
TL;DR: On a 5x4 mm², 3F cooker feed with 16 A breakers, "The oven MUST be on a separate circuit" [Elektroda, Anonymous, post #17294421] One case used 14 circuits on 84 m² [Elektroda, Anonymous, post #17294972] Sharing N between hob/oven is unacceptable [Elektroda, Anonymous, post #17294421]
Why it matters: This FAQ helps apartment owners and installers fix or plan safe kitchen power for hobs/ovens when walls are already finished.
Quick Facts
- Stationary appliances ≥2 kW should run on separate circuits; the oven must not share with others [Elektroda, Anonymous, post #17294421]
- Do not use the “free phase” from a 5x4 mm² hob feed for the oven; that would share the neutral (N), which is unacceptable [Elektroda, Anonymous, post #17294421]
- One-RCD-for-all is “sufficient, although inconvenient,” and can nuisance-trip with many switched‑mode power supplies [Elektroda, Anonymous, post #17294865]
- In-thread hardware used: Hager MBN216E (hob, 16 A) and MBN116E (oven, 16 A) [Elektroda, Tomotron, post #17300510]
- Real-world example: 14 circuits serving an 84 m² flat to improve selectivity and convenience [Elektroda, Anonymous, post #17294972]
Quick Facts
- Stationary appliances ≥2 kW should run on separate circuits; the oven must not share with others [Elektroda, Anonymous, post #17294421]
- Do not use the “free phase” from a 5x4 mm² hob feed for the oven; that would share the neutral (N), which is unacceptable [Elektroda, Anonymous, post #17294421]
- One-RCD-for-all is “sufficient, although inconvenient,” and can nuisance-trip with many switched‑mode power supplies [Elektroda, Anonymous, post #17294865]
- In-thread hardware used: Hager MBN216E (hob, 16 A) and MBN116E (oven, 16 A) [Elektroda, Tomotron, post #17300510]
- Real-world example: 14 circuits serving an 84 m² flat to improve selectivity and convenience [Elektroda, Anonymous, post #17294972]
Is it OK to put dishwasher, refrigerator, oven and hood on one circuit?
No. Forum consensus: the oven must be on its own circuit because it’s a stationary load ≥2 kW. Combining many heavy and continuous loads raises nuisance trips and complicates isolation. One expert put it plainly: “The oven MUST be on a separate circuit.” [Elektroda, Anonymous, post #17294421] Another noted the kitchen needed at least separate circuits for dishwasher, oven, and utility sockets [Elektroda, mawerix123, post #17294754]
Can I use the “free phase” from a 5x4 mm² 3‑phase hob feed to power the oven?
No. The hob uses 2 phases + N; the oven would use the third phase + the same N. That makes the neutral common, which is unacceptable. “You can not,” as an expert replied [Elektroda, Anonymous, post #17294421] Even if it “works,” you can’t fully isolate each appliance safely [Elektroda, Anonymous, post #17294743]
What does “separate circuit” actually mean for an oven or hob?
A dedicated final circuit from the distribution board with its own protective device(s) and neutral, not shared with other appliances. You must be able to switch off and service that circuit independently. “You must be able to turn off the circuit, not just half,” an expert emphasized [Elektroda, Anonymous, #17294743; Elektroda, Anonymous, #17294421].
Is a 16 A breaker enough for my induction hob or oven?
It depends on the appliance rating. In the thread, the hob initially had a 16 A three‑pole MCB [Elektroda, Tomotron, post #17294302], and later the user installed Hager MBN216E (hob, 16 A) and MBN116E (oven, 16 A) [Elektroda, Tomotron, post #17300510] Match breaker size to the manufacturer’s nameplate and connection diagram.
Why is sharing the neutral (N) between hob and oven a problem?
It violates good practice for separate circuits and complicates safe isolation. The proposed split would make hob and oven share N from the same 5x4 mm² cable, which was flagged as unacceptable [Elektroda, Anonymous, post #17294421] You also lose the ability to fully de‑energize one appliance without affecting the other [Elektroda, Anonymous, post #17294743]
Is one RCD for the whole apartment acceptable?
It is “sufficient, although inconvenient,” per an expert. It can be problematic with many switched‑mode power supplies (edge-case: nuisance tripping) [Elektroda, Anonymous, post #17294865] Another user noted this setup can leave you in the dark until help arrives [Elektroda, Zbigniew 400, #17294874]. Consider more selective protection where possible.
Who signs off or checks installations in new apartment blocks?
One pro observed that often no one meaningfully verifies them. Frequently there isn’t even a formal project—just verbal agreements about socket locations [Elektroda, Anonymous, #17294860; Elektroda, Zbigniew 400, #17294853]. This explains why questionable kitchen circuit groupings are encountered.
I can’t chase walls—how do I add a separate oven circuit now?
Walls and floors are finished in your scenario [Elektroda, Tomotron, post #17294302] Try this minimal-impact approach:
- Plan a surface route: above cabinets, inside plinths, or via ceiling voids.
- Use surface trunking or conduit to the oven niche, keeping runs short and protected.
- Install a dedicated MCB/RCBO in the board and pull a new cable on that route (qualified electrician).
Will splitting the hob feed into double‑pole (hob) and single‑pole (oven) breakers fix it?
No. That layout still shares the neutral, which experts flagged as unacceptable [Elektroda, Anonymous, post #17294421] The thread author later fitted Hager MBN216E for the hob and MBN116E for the oven (both 16 A), but the safety concern about a common N remains [Elektroda, Tomotron, post #17300510]
How many kitchen circuits should I aim for in practice?
One expert said you’re missing at least three: dishwasher, oven, and utility sockets, with a possible fourth for a microwave [Elektroda, mawerix123, post #17294754] More circuits improve selectivity and convenience during faults and maintenance [Elektroda, Anonymous, post #17294743]
I often see hob+oven on one 5x4 mm² cable—is that ever acceptable?
Pros report seeing it in new blocks, but they criticize it. It may “work,” yet it prevents proper isolation and reflects corner‑cutting rather than good design [Elektroda, Zbigniew 400, #17294716; Elektroda, Anonymous, #17294743]. Follow the separate‑circuit guidance for safety and serviceability [Elektroda, Anonymous, post #17294421]
How many circuits are typical in a modern flat? Any real example?
A pro shared a real case: 14 circuits in an 84 m² apartment to improve selectivity, even after accepting some existing constraints [Elektroda, Anonymous, post #17294972] More circuits reduce nuisance outages and simplify future changes [Elektroda, Anonymous, post #17294743]
