Додавання 3-позиційного реле вводу резерву до щитової: схема та підключення

mhariw032 wrote:

@ElektrodaBot
Доброго дня, як в цю щитову добавити 3х позиційне реле вводу резерва
https://obrazki.elektroda.pl/5670860300_1764600475.jpg

Initial assessment of available information
- Your board (photo) is single‑phase, DIN‑mounted, with:
- 1 two‑pole RCD (IEK, 25 A, 30 mA) as the incomer.
- 2 single‑pole MCBs (C16 and C10) as outgoing feeders.
- Separate busbars for neutral and (apparently) protective conductors.
- You want to add a three‑position reserve input device (I–0–II), i.e., a manual transfer switch or motorized ATS, often called “реле вводу резерву / АВР”.

Core point: in this layout the transfer device must be installed upstream of the RCD so that the RCD continues to protect all loads irrespective of the source.

Direct answer to the question
- Insert a 2‑pole, break‑before‑make, I–0–II transfer switch (manual or motorized) between the incoming sources (Grid and Reserve) and the existing RCD. Switch both Phase and Neutral; do not switch PE.
- Minimum rating: 230 V AC, ≥40 A, utilization category AC‑22A (mixed resistive/inductive), with mechanical interlock inherent to I–0–II. Short‑circuit withstand must be compatible with your upstream protection.
- Wiring (single‑phase):
- Grid L,N → Switch “I” inputs.
- Reserve L,N → Switch “II” inputs.
- Switch common outputs Lout,Nout → RCD input.
- RCD output → existing MCBs → loads.
- All PE conductors from both sources remain permanently bonded to the PE bar.

Detailed problem analysis
1. Why 2‑pole switching is mandatory
- With a generator/inverter as Reserve, neutrals of Grid and Reserve must not be commoned. A 2‑pole device isolates both L and N and prevents neutral backfeed, RCD maloperation, and ground‑fault hazards. Leave PE unswitched and continuous.

2. Device selection and ratings
- Type: I–0–II changeover switch (manual) or motorized transfer switch (ATS). For small boards, modular DIN versions exist.
- Current: Your incomer RCD is 25 A. Use a switch with ≥1.25× margin → 32–40 A minimum; 40 A is a pragmatic choice.
- Category: AC‑22A or better (per IEC/EN 60947‑3), suitable for mixed loads.
- Making/breaking: “Break‑before‑make” is mandatory; never parallel the sources.
- Space: DIN modules typically 3–6M. Your enclosure looks tight; be prepared to add a small adjacent enclosure or replace the box with a wider one.

3. Recommended topology
- Grid side should remain protected by its upstream fuse/MCB (usually near the meter).
- Reserve side should have its own 2‑pole MCB or fuse (typically 16 A for a 3–5 kW portable generator) placed as close as practicable to the inlet.
- Provide a proper inlet (CEE 16 A 2P+PE or manufacturer’s interlocked socket). Never use “male‑to‑male” cords.

4. Neutral‑PE bonding and RCD type
- If the Reserve is a generator with a floating neutral or an inverter with output electronics, ensure only one N‑PE bond exists in the system.
- Best practice: switch Neutral in the transfer device and let the N‑PE bond reside either at the grid transformer (typical TN‑C‑S/TN‑S) or inside the generator per its manual (separately derived system). Do not duplicate N‑PE bonds.
- Many inverters/generators inject DC/half‑wave leakage. Replace the existing Type AC RCD with Type A 30 mA (or B if the inverter manufacturer explicitly requires), to avoid nuisance trips and to maintain protection effectiveness.

5. Wiring diagram (conceptual, single‑phase)
- Sources and protection
Grid L——MCB/Fuse—┐
├──[I–0–II 2P]——Lout——[RCD 2P]——→ MCBs → Loads
Grid N———————┘ Nout———[RCD]——→ Neutrals bar
Reserve L—MCB/Fuse—┐
└──[I–0–II “II”]
Reserve N———————┘
PE (Grid + Reserve)———————————————→ PE bar (unswitched)

6. Control (if you choose automatic ATS)
- Use two mechanically interlocked contactors or a ready‑made motorized transfer module with:
- Source‑presence/quality monitor (U/frequency/phase).
- Delay on transfer to Reserve (e.g., 5–10 s) and on retransfer to Grid.
- Generator start/stop output (if applicable).
- Still switch both L and N for a single‑phase system.

7. Conductor sizing and terminations
- Match conductors to the protective device of each branch. For a 25 A incomer, 4 mm² Cu is a common minimum; 2.5 mm² may be acceptable for 16–20 A depending on installation method and local code.
- Use ferrules on fine‑stranded wires; torque terminals to manufacturer specs; label all new conductors and devices.

8. Mechanical notes for your specific board
- The current device row appears fully occupied. A 40 A I–0–II will likely not fit without:
- Replacing the enclosure with a wider model, or
- Adding a small adjacent box for the transfer switch and reserve MCB/inlet.
- Keep wiring neat and segregated; maintain minimum bending radii and clearances around the RCD test button.

Current information and trends
- Modular DIN transfer switches per IEC/EN 60947‑3 are now widely available with compact footprints and motorized options.
- For hybrid inverters (2023–2025 models), manufacturers increasingly require at least RCD Type A on the backed‑up circuits. Plan for this upgrade simultaneously.

Supporting explanations and details
- Break‑before‑make prevents dangerous paralleling of two unsynchronized sources (grid/generator), which can cause severe overcurrent and mechanical stress.
- Switching Neutral avoids shared‑neutral faults and ensures the RCD always “sees” return current from the active source only.

Ethical and legal aspects
- Work on service equipment must be performed de‑energized and by a qualified electrician. Local electrical codes (e.g., IEC 60364/PUE‑compatible rules) may require inspection when adding a generator inlet or transfer equipment.

Practical guidelines (step‑by‑step)
1. Power down and lock out both sources.
2. Mount the I–0–II 2P switch (and Reserve 2P MCB) in the new/expanded enclosure.
3. Move the existing Grid L,N that now feed the RCD to the I–0–II “I” inputs.
4. Wire the I–0–II common outputs to the RCD input terminals.
5. Install a proper Reserve inlet and route its L,N,PE via the Reserve MCB to the I–0–II “II” inputs; connect Reserve PE to the PE bar.
6. Verify neutral/earth scheme as per generator/inverter manual; remove any duplicate N‑PE bond if present.
7. Replace RCD with Type A 30 mA if Reserve is inverter‑based (recommended regardless).
8. Test sequence:
- Continuity/insulation tests.
- Function test with no load: I → 0 → II and back.
- Generator start, load transfer under moderate load, RCD trip test on both sources.
- Re‑transfer to Grid with delays as applicable.

Possible disclaimers or additional notes
- Color coding in your photo looks inconsistent (many yellow conductors). For clarity and safety, use standard colors: Brown/Black (L), Blue (N), Yellow‑Green (PE).

Suggestions for further research
- Look up DIN rail I–0–II transfer switches 2P 40 A, AC‑22A, and motorized ATS modules compatible with 230 V single‑phase.
- Review your generator/inverter manual for N‑PE bonding and RCD type requirements.

Brief summary
Install a 2‑pole I–0–II transfer switch ahead of the existing RCD so that Grid and Reserve each feed the board exclusively. Switch both L and N, keep PE unswitched, provide proper Reserve overcurrent protection and inlet, and upgrade the RCD to Type A if the Reserve is an inverter. Given your enclosure is small, plan on an add‑on box or a larger panel.

Questions for the user
- What is the Reserve source (portable generator model, inverter/UPS, or second utility feed)?
- Do you want manual changeover or automatic transfer?
- Available free DIN modules or are you open to adding a small adjacent enclosure?
- Earthing system (TN‑S/TN‑C‑S/TT) at your site?
- Maximum expected backup load (kW/A) so we can size the switch and cabling precisely?