Description
The Vaisala CARBOCAP® GMP251 carbon dioxide probe is a smart, self-contained probe that measures the percentage of CO₂ present in life science incubators, cold storage facilities, fruit and vegetable transport, and any demanding application requiring stable and accurate CO₂ concentration measurements. Its operating temperature range is -40 to +60 °C, and its measurement range is 0 to 20% CO₂.
The GMP251 probe utilizes Vaisala's unique second-generation CARBOCAP® technology, which delivers exceptional stability. The GMP251's lifespan is extended by a new type of infrared (IR) light source that replaces the traditional incandescent bulb. It also features comprehensive temperature and pressure compensation for CO₂ measurements – with integrated temperature measurement for compensation. The sensor head is heated to prevent condensation. Digital output with RS-485 interface: Modbus and Vaisala industrial protocol. The product always comes with a calibration certificate.
Belongs to the Indigo product range
The GMP251 probe is part of the Indigo product family and can also be connected to the Indigo500, Indigo300, and Indigo200 transmitters to expand functionality, for example, display or relays.
The GMP251 probe can also be used with the free Insight PC software.
For spot checks, we recommend the Indigo80 handheld indicator.
The GMP251 replaces the following discontinued products: GMM221 and GMT221. Please note that spare parts and accessories are still available for the GMP221 probe and can be purchased in the Vaisala online shop.
To learn more about the product, watch the video below.
Features
- CO2 Measurement Range: 0 to 20%
- Smart, self-contained probe with analog (V, mA) and digital (RS485) outputs
- Superior long-term stability thanks to second-generation CARBOCAP® technology
- Operating Temperature: -40 to +60 °C
- IP65 rated enclosure
- Temperature and Pressure Compensation
- Integrated temperature measurement for pressure compensation
- CO₂
- Compensation for gases present, O₂, and humidity
- Heated sensor head to prevent condensation
Key Advantages
Easy to Use and Clean
The GMP251 is an all-in-one probe that is quick and easy to install. The probe is resistant to dust and most chemicals, including H₂O₂ and other alcohol-based cleaning agents. Its smooth surface makes cleaning easy.
Reliability and Accuracy
Thanks to its wide operating temperature range, the GMP251 probe is suitable for a variety of applications. It provides accurate and stable measurements, even under varying conditions.








