Rosemount Instrument Ordering Code Guide

In industrial automation, Rosemount instruments are widely recognized for their accuracy, reliability, and long-term stability.
Beyond the product name itself, what truly defines a Rosemount instrument is its ordering code—a structured sequence of letters and numbers that specifies measurement type, mechanical design, materials, communication protocol, and certifications.
This article explains how Rosemount model codes work, using the Rosemount 3051 pressure transmitter series as a representative example to illustrate the logic behind Rosemount ordering codes.

However, what truly determines whether a Rosemount 3051 transmitter is correctly selected and reliably applied is not the product name itself, but the complete ordering code behind it.
For example:

3051CD3A02A1JM6E5S5Q4Q8A0188

This long string is not random. It is a highly structured engineering language that defines exactly what the instrument is—and what it is not.

1. What a 3051 Model Code Really Is

In the Emerson online configurator, building a Rosemount 3051 model is essentially a process of answering a sequence of engineering questions:
– What variable is being measured?
– What is the required pressure range?
– What physical structure is needed?
– What process medium will be in contact with the sensor?
– Are explosion-proof or safety certifications required?
Each answer adds another character to the model code.In other words, a full Rosemount 3051 model code is not just a product identifier — it is a complete configuration instruction.

2. Base Platform: What 3051C / G / A Actually Mean

Code	Meaning
3051C	Coplanar Differential Pressure Transmitter
3051G	Gauge Pressure Transmitter
3051A	Absolute Pressure Transmitter

📌 This step defines the mechanical structure, not just the pressure type.

3.Measurement Type and Sensor Range: Can It Measure Your Process?

After the base platform, the model code specifies:

• Pressure measurement type (DP, GP, AP)
• Sensor range code

⚠️ Important engineering note:

A range code does not represent a fixed measuring range by itself.
It corresponds to a sensor capability table that defines the allowable lower and upper range limits.

💡 Engineering note: Sensor range codes do not equate to actual setpoint ranges; specific upper and lower limits must be verified against Emerson’s official range tables.

4.Output Signal: How the Transmitter Communicates

The model code also encodes the output and communication protocol, such as:

• 4–20 mA with HART
• FOUNDATION Fieldbus
• PROFIBUS

This directly determines compatibility with DCS and PLC systems.

5.Process Connection and Wetted Parts: Can It Be Installed and Will It Last?

For coplanar models like the 3051C, a significant portion of the ordering code defines:

• Flange standard and size
• Flange material
• Drain/vent configuration
• Isolating diaphragm material (316L SS, Hastelloy, Tantalum, etc.)
• Sensor fill fluid type

📌 These options are critical in corrosive, high-temperature, or chemically aggressive applications.

6.Housing, Electrical Entry, and Certifications: Can It Enter Your Project?

模型代码的后半部分通常会规定：

• Housing material (aluminum or stainless steel)
• Explosion-proof approvals (ATEX, IECEx, FM)
• SIL functional safety
• Factory test or project-specific options

These characters may not affect measurement performance, but they often determine whether the instrument meets regulatory and project requirements.

7.Why Are Rosemount 3051 Model Codes So Long?

In large industrial projects:

One incorrect character can result in:

• Installation incompatibility
• Failed inspection or certification
• Costly reordering and downtime

Longer model codes reduce ambiguity.

They ensure that what is quoted, manufactured, delivered, and installed is exactly the same instrument.

结论：理解代码意味着理解工具。

简短的型号名称用于市场推广。
完整的订购代码则用于工程、采购和现场安装。
如果您正在查看完整的罗斯蒙特 3051 型号代码，并且不确定某些选项是否真正符合您的工艺条件，我们可以根据艾默生官方的选型逻辑协助您验证配置，从而避免出现纸面上看起来正确但实际现场却无法正常工作的情况。

For detailed technical specifications, application advice, or commercial inquiries regarding a wider range of industry brands, please contact us via WhatsApp: +86 132 7933 7527 or Email: info@antletstech.com. Our experienced engineering team is ready to support your project.