What is a CMMS? A plain explanation for maintenance teams
- Definition — a CMMS is software that keeps track of your machines, the work done on them, the parts used and the maintenance that is due.
- What it is good at — work orders, schedules, parts stock and history. The record of what happened.
- What it is not — it does not tell a technician how to do the repair. That knowledge lives in manuals, in people and, with Opero, in a knowledge base connected to the CMMS.
CMMS meaning
CMMS stands for computerised maintenance management system. It is the software a maintenance department uses to keep track of its machines and the work done on them.
A CMMS answers questions like these: Which machines do we have? What is due for service this month? Who is working on the broken conveyor? Which parts did we use on it last time? How many hours has line 2 been down this year?
Well-known products include MaintainX, eMaint, Fiix, IBM Maximo and the maintenance modules of SAP and Microsoft Dynamics. Some companies still run their maintenance from spreadsheets. A CMMS replaces those spreadsheets with one system that everyone can see.
What a CMMS keeps track of
Most systems have the same core parts:
- Assets. A list of your machines and equipment, often with location, serial number and supplier.
- Work orders. A ticket for each job: what needs to be done, on which asset, by whom, by when. Work orders are the heart of the system.
- Preventive maintenance schedules. Recurring jobs that the system creates automatically, every 500 running hours or every three months, for example.
- Spare parts and inventory. What is in the storeroom, where it is, and when to reorder.
- History. Every completed work order, with time spent and parts used. Over the years this becomes the maintenance record of each machine.
- Reports. Downtime per machine, cost per asset, open work orders, overdue preventive maintenance.
CMMS versus EAM versus ERP
The three terms overlap and sales teams use them loosely.
A CMMS is about maintenance. Work orders, schedules, parts.
An EAM (enterprise asset management) system covers the whole life of an asset: buying it, installing it, maintaining it, replacing it. In practice, many EAM systems are a CMMS with finance and procurement features added.
An ERP (enterprise resource planning) system runs the business: orders, invoices, stock, accounting. Large ERP systems have a maintenance module, which is why some companies use SAP as their CMMS.
If you are a maintenance manager choosing a tool, you most likely need a CMMS. If finance already runs an ERP with a maintenance module, you may already have one.
What a CMMS does well
A good CMMS gives you three things. Order, because every job is a work order with an owner and a date. Memory, because the history of each machine is in one place. Discipline, because preventive maintenance comes up on time whether or not someone remembers it.
Plants that go from spreadsheets to a CMMS usually see fewer missed services and a clearer picture of which machines cost the most.
What a CMMS does not do
A CMMS records that a repair happened. It does not explain how to do it.
Open a typical closed work order and you find: “Replaced sensor, tested OK.” Which sensor? Which setting? What did the technician check first? That knowledge went home with the technician.
The CMMS also does not read your manuals, your supplier’s service bulletins or the email where a colleague described a workaround. When a technician stands at a stopped machine, the CMMS tells them the machine has stopped five times this year. It does not tell them what to do now.
That gap is where most unplanned downtime hides. The record exists, the knowledge does not.
How AI fits next to a CMMS
The useful place for AI is on top of the CMMS, not instead of it.
Opero connects to your CMMS, reads the work orders and history, and connects them to your manuals, drawings, service bulletins and recorded repairs. A technician asks, in plain words, “the filling machine shows fault 31, what do I do?” and gets the steps with the source next to them: the manual page, the last work order on that fault, or a video a colleague recorded.
When the job is done, the technician films or dictates a short report. Opero writes it up and sends it to the CMMS as a finished work order, with the parts and the steps. The next person who meets fault 31 finds a real answer instead of “tested OK.”
The CMMS stays the system of record. Opero makes the record useful at the machine.
Questions people ask about CMMS
Do we need a CMMS before we can use AI? No. Opero also works from manuals, documents and recorded repairs alone. A CMMS adds the maintenance history, which makes the answers better.
Which CMMS does Opero connect to? SAP, Microsoft Dynamics, ServiceNow, IFS and others. See the integrations page for the current list.
Is a work order the same as a service report? A work order is the request and the plan. A service report is what was actually done. In many plants the second one is thin or missing, and that is the part Opero helps with.
If you want to see Opero next to your own CMMS, book a 20-minute demo.