Ask four systems in an oil and gas operation how many wells the company runs and you may get four different answers. SCADA knows the wells it polls, the historian knows the ones it stores, the maintenance system knows the ones with work orders, and the ERP knows the ones on the books - and their lists rarely match perfectly. Master data management is the discipline of keeping one authoritative record of each asset so those systems finally agree. This guide explains what master data is in an OT context, what a golden record and reconciliation mean, and how cloud SCADA can serve as the source of truth for real-time asset state.
Master Data Management in one line: Master data management (MDM) is the practice of maintaining a single authoritative record for each core business entity - assets, wells, equipment, units, and sites - so that every system referencing that entity uses consistent, agreed information. In operational technology it keeps SCADA, the historian, the maintenance system, and the ERP working from the same asset list and the same identities, rather than each maintaining its own drifting copy. The authoritative record for an entity is often called its golden record.
Master data is the relatively stable reference information that describes the things an operation acts upon - the well, the pump, the separator, the site, the unit - as opposed to the fast-moving readings and events that flow through those things. A well's identifier, name, location, spud date, and equipment configuration are master data; the pressure it reported this second is transactional, time-series data. The distinction matters because master data is shared across many systems and changes slowly, so an error in it is both widespread and long-lived, while transactional data is high-volume and short-lived. MDM focuses its effort on the slow-moving reference layer precisely because getting it wrong contaminates everything built on top.
In OT specifically, master data includes asset hierarchies, equipment records, tag registries, and the relationships between them - which pump belongs to which pad, which meter belongs to which well. These records are consumed by SCADA for display and control, by the historian for organizing time-series, by the maintenance system for work orders, and by the ERP for accounting and reporting. Each of those systems has traditionally kept its own copy, entered by different people at different times, which is exactly how the same well ends up with three spellings, two identifiers, and one wrong location across the enterprise.
Master data management does not try to move all of this into one database. It establishes which system is authoritative for each attribute, defines the shared identities, and keeps the copies in the various systems aligned to those authoritative values. The goal is not a single monolith but a single agreed answer to questions like what is this asset called and where does it sit in the hierarchy.
A golden record is the single, trusted version of the truth for one entity, assembled and maintained so that when systems disagree, there is a defined right answer. Building a golden record usually means gathering the various copies of an asset from every system, matching the ones that refer to the same real thing, resolving conflicts between their attributes according to defined rules about which source is authoritative for which field, and publishing the reconciled result back out. The golden record for a well might take its official name and location from a land or regulatory system, its equipment configuration from the maintenance system, and its live operating state from SCADA, each field sourced from wherever it is most authoritative.
Reconciliation is the ongoing work of keeping those copies aligned. New wells are drilled, equipment is replaced, sites are renamed, and assets are sold or acquired, and every such change has to propagate to every system that holds a copy. Reconciliation compares the systems, flags mismatches - a well present in SCADA but missing from the ERP, an identifier that differs between the historian and the maintenance system, a location that two systems disagree on - and drives those differences to resolution. Without it, the lists drift apart again as soon as the initial cleanup is done.
The cost of skipping this shows up in reporting. When the systems disagree on how many assets exist or what they are called, roll-ups do not add up, allocation and production accounting break, and a downtime report cannot be trusted because it is not clear the report covered the same set of wells the field actually runs. A great deal of the manual reconciliation that consumes engineering and accounting time each period exists only because there is no maintained golden record to reconcile against. MDM replaces that recurring manual matching with a governed, authoritative list.
MDM is often discussed in terms of static attributes, but assets also have a live state - running or down, flowing or shut in, in alarm or normal - and that real-time picture is master data of a kind that the traditional systems of record are poorly placed to hold. An ERP or maintenance system knows an asset exists but has no idea whether it is producing right now. This is where cloud SCADA fits naturally into an MDM strategy: it is the system continuously in touch with the physical asset, so it is the most authoritative source for the asset's current operating state.
Merobix reads live from wells, tank batteries, compressors, and gathering systems over Modbus, DNP3, OPC UA, and MQTT, which makes it a candidate source of truth for the dynamic attributes of each asset - its current status, latest readings, and operating mode - while the ERP and maintenance systems remain authoritative for commercial and static attributes. Feeding SCADA's real-time state into a golden record means the enterprise view of an asset is not just what it is on paper but what it is doing at this moment, which is exactly the attribute other systems lack. Because the platform already maintains a canonical asset and tag identity, it can align its own records to the shared master identities rather than adding yet another divergent list.
The practical benefit is a consistent asset picture that spans planning and reality. When the maintenance system, the accounting system, and the live monitoring system all reference the same asset identities and SCADA supplies the current state, a report can combine what an asset is, what work it needs, and whether it is running right now without a reconciliation step in between. For an operator managing many dispersed sites, that alignment between the authoritative asset list and continuous real-time state is what makes enterprise reporting trustworthy.
A golden record is the single, trusted version of the truth for one entity, such as a well or a piece of equipment. It is assembled by matching the copies of that entity across systems and resolving conflicts according to rules about which source is authoritative for each field. When systems disagree, the golden record provides the defined right answer.
When SCADA, the historian, the maintenance system, and the ERP disagree on how many assets exist or what they are called, roll-ups and allocations do not add up and reports cannot be trusted to cover the same set of assets the field actually runs. Much of the manual reconciliation that consumes time each reporting period exists only because there is no maintained golden record to align against.
For real-time state, yes. SCADA is the system continuously in touch with the physical asset, so it is the most authoritative source for whether an asset is running, flowing, or in alarm right now. Commercial and static attributes usually stay authoritative in the ERP or maintenance system, while cloud SCADA supplies the dynamic operating state that those systems cannot see.
This page references the protocol specifications published by the organizations below. Editions, product capabilities, and documentation change over time - confirm current requirements and specifications directly with the source.
Last reviewed: July 27, 2026. Merobix is not affiliated with, endorsed by, or sponsored by these organizations; their names are used only to identify the standards and products discussed.
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