# Engineering changes

> Change number (revision release with a validity date) and approved change request — statuses, locking, approval and the effect on revisions.

URL: https://erpdocs.corexlogic.com/en/uretim/ekranlar/muhendislik-degisiklikleri

A **change number** determines **from which day** BOM and routing revisions become valid. If a number is selected
when a revision is published, the revision is valid from the number's valid-from date; until that day the previous
revision remains effective. MRP explodes a planned order with the BOM valid on its start date.

A **change request** (numbered `DTL-`) records the reason for the change, its impact and the objects it affects; when
approved, it opens the change number itself.

- **Type:** Screen
- **Module:** Manufacturing
- **Menu path:** Üretim › Ana Veriler › Mühendislik Değişiklikleri · Değişiklik Talepleri (Production › Master Data › Engineering Changes · Change Requests)
- **Screen route:** `/erp/manufacturing/engineering-changes`
- **Required permission:** `erp-manufacturing-engineering-changes.view (görme) · .create (değişiklik numarası ve talep açma) · .edit (değiştirme, kilitleme)`

## Engineering Changes list

![Engineering Changes list](https://erpdocs.corexlogic.com/en/en/img/screens/uretim/muhendislik-listesi.png)
1. New change number
2. Valid-from date of the number
3. Revisions released with it
4. Active or Locked

| Column | Meaning |
|---|---|
| **Değişiklik No** (Change No.) | `MDN-yyyy-nnnnnn`; assigned on save. |
| **Başlık** (Title) | Short name of the change. |
| **Geçerlilik** (Validity) | The first day on which revisions published with the number are valid. |
| **Revizyon** (Revisions) | The number of revisions published with this number. |
| **Durum** (Status) | **Etkin** (Active) or **Kilitli** (Locked). |
| **Oluşturan** (Created By) | The user who opened the number. |

The **Değişiklik Numarası Oluştur** (Create Change Number) form: **Başlık** (Title), **Değişiklik nedeni** (Reason for
change) (both required), **Geçerlilik başlangıcı** (Valid from; required). Details:
[Create an engineering change](https://erpdocs.corexlogic.com/en/uretim/islemler/muhendislik-degisikligi-olusturma).

### Statuses and actions

| Status | Meaning | Actions (in the details) |
|---|---|---|
| **Etkin** (Active) | Can be selected in the publish window. | **Değiştir** (Change; title, reason, date), **Kilitle** (Lock). |
| **Kilitli** (Locked) | Cannot be selected when publishing a new revision; releases already made with this number remain valid. | **Değiştir** (Change), **Kilidi Kaldır** (Unlock). |

The details page shows **Durum** (Status), **Başlık** (Title), **Geçerlilik başlangıcı** (Valid from; **Yürürlükte**
(In effect) if it has taken effect), **Oluşturan** (Created By), **Değişiklik nedeni** (Reason for change) and **Nesne
Listesi — Ürün Ağacı Revizyonları** (Object List — BOM Revisions; the revisions published with this number).

Rules for changing the validity date:

- If the number has taken effect and is in use, the date cannot be changed; open a new change number.
- Moving the date also moves the revisions published with the number; it cannot be moved into the past.
- Validity follows the revision sequence: a revision cannot become valid earlier than the previous revision or later
  than the next revision.

## Change Requests

![Change Requests list](https://erpdocs.corexlogic.com/en/en/img/screens/uretim/muhendislik-talep-listesi.png)
1. New change request
2. Draft, Pending Approval, Approved…
3. Number opened on approval

| Column | Meaning |
|---|---|
| **Talep** (Request) | `DTL-yyyy-nnnnnn`. |
| **Başlık**, **Durum** (Title, Status) | The request's name and status. |
| **Önerilen Geçerlilik** (Proposed Validity) | The day proposed by the requester; on approval it becomes the validity of the number opened. |
| **Değişiklik No** (Change No.) | The `MDN-` number opened on approval. |
| **Nesne** (Objects) | Number of affected objects. |
| **Açan** (Opened By) | The user who opened the request. |

The **Değişiklik Talebi Aç** (Open Change Request) form: **Başlık** (Title), **Neden** (Reason; required), **Etki notu**
(Impact note; cost, stock, open orders…), **Önerilen geçerlilik** (Proposed validity; required) and **Etkilenen
Nesneler** (Affected Objects) — select the object type (**Ürün ağacı** (BOM), **Rota** (Routing), **Ürün** (Product))
and add a record with **Nesne ekle** (Add object); at least one object is required. **Taslağı Kaydet** (Save Draft)
saves the request as **Taslak** (Draft).

![Draft change request](https://erpdocs.corexlogic.com/en/en/img/screens/uretim/muhendislik-talep-detay.png)
1. Submit — for approval or approved directly
2. Edit — draft only
3. Cancel
4. Change number is opened on approval

### Request statuses

| Status | Actions |
|---|---|
| **Taslak** (Draft) | **Düzenle** (Edit), **Gönder** (Submit), **İptal Et** (Cancel). |
| **Onay Bekliyor** (Pending Approval) | Approver: **Onayla** (Approve) or **Reddet** (Reject; rejection reason required; the request returns to **Taslak** (Draft)). **İptal Et** (Cancel). |
| **Onaylandı** (Approved) | No actions; the `MDN-` number opened is shown in the **Değişiklik numarası** (Change number) field. |
| **İptal** (Cancelled) | No actions. |

- **Gönder** (Submit): if an approval template for change requests is defined in the setup, the request becomes **Onay
  Bekliyor** (Pending Approval); if not, it becomes **Onaylandı** (Approved) directly and the change number is opened
  immediately (in the demo environment DTL-2026-000001 → MDN-2026-000002).
- You cannot approve a request you opened yourself; another approver makes the decision.
- An approved or cancelled request cannot be cancelled.

## Effect on revision release

- The **Değişiklik numarası** (Change number) selector in the publish windows of the [BOM](https://erpdocs.corexlogic.com/en/uretim/ekranlar/urun-agaclari),
  [routing](https://erpdocs.corexlogic.com/en/uretim/ekranlar/rotalar) and [component management](https://erpdocs.corexlogic.com/en/uretim/ekranlar/urun-agaci-bilesen-yonetimi)
  screens lists only **Etkin** (Active) numbers; leaving it blank means "valid from today".
- If an approved request is required in **Üretim Ayarları** (Production Settings), a revision can be published only
  with a number opened from an approved request.

## Common messages

| Message | English meaning | Cause |
|---|---|---|
| MDN-… kilitli — yeni yayında kullanılamaz. | MDN-… is locked — it cannot be used for a new release. | A locked number was selected; use **Kilidi Kaldır** (Unlock) or another number. |
| Revizyon yalnız onaylı bir değişiklik talebinin numarasıyla yayınlanır (Üretim Ayarları) — talep açıp onaylatın. | A revision can be published only with the number of an approved change request (Production Settings) — open a request and have it approved. | The setting is on and no number was selected. |
| MDN-… onaylı bir değişiklik talebinden açılmadı — yayın için onaylı talebin numarası gerekir. | MDN-… was not opened from an approved change request — releasing requires the number of an approved request. | The setting is on and the number was opened manually. |
| MDN-… gg.aa.yyyy tarihinde yürürlüğe girdi — geçerlilik tarihi değiştirilemez; yeni bir değişiklik numarası açın. | MDN-… took effect on dd.mm.yyyy — the validity date cannot be changed; open a new change number. | An attempt was made to change the date of a number in effect. |
| Kullanımdaki değişikliğin geçerliliği geçmişe alınamaz. | The validity of a change in use cannot be moved into the past. | The date was moved into the past. |
| Revizyon N gg.aa.yyyy tarihinden geçerli olamaz — önceki revizyon M gg.aa.yyyy tarihinden geçerli; geçerlilik revizyon sırasıyla ilerler. | Revision N cannot be valid from dd.mm.yyyy — the previous revision M is valid from dd.mm.yyyy; validity follows the revision sequence. | The number's date is earlier than the previous revision. |
| Talep en az bir etkilenen nesne (ürün ağacı, rota ya da ürün) taşır. | A request must have at least one affected object (BOM, routing or product). | No object was added. |
| Kendi açtığınız değişiklik talebini onaylayamazsınız. Kararı başka bir onaycı vermeli. | You cannot approve a change request you opened yourself. Another approver must make the decision. | Self-approval was attempted. |
| Red gerekçesi zorunludur. | A rejection reason is required. | Rejection without a reason. |
| DTL-… taslak değil — değiştirilemez. | DTL-… is not a draft — it cannot be changed. | An attempt was made to edit a submitted request. |

## Related

- [Create an engineering change](https://erpdocs.corexlogic.com/en/uretim/islemler/muhendislik-degisikligi-olusturma)
- [Publish a BOM](https://erpdocs.corexlogic.com/en/uretim/islemler/urun-agacini-yayinlama)