Compare the operating models
A fictional buyer asks about Pump-P. Later a contact reports installed serial P991 at S1. Pump-P is a model; P991 is a customer unit with site and service history.
| Business requirement | Product model link | Installed unit link |
|---|---|---|
| Pre-sale question | Specification and offer | No unit exists yet |
| P991 service | Model cannot identify unit | Unit, customer, site, history |
| Several same-model pumps | Shared Pump-P | Separate unit records |
Work through the chosen model
Map enquiry → Pump-P and case → P991 → model/site/customer. One model has many units. A replacement offer does not replace the old unit’s service record.
- Clarify model or unit question
- Select correct context
- Attach relevant follow-up
Units support service continuity but require installation and transfer upkeep. Model-only enquiries remain simple until a real unit relationship exists.
Pre-sale has no invented serial. Service names P991/S1 and leaves other Pump-P units’ histories unchanged.
When the other model fits
Customer has three Pump-P units but no serial/location is given. Select P991 automatically?
Show the worked answer
No. Keep the affected unit unresolved until identified.