为您的HVAC应用程序选择合适的CO2传感器

The environment in which you’re measuring CO₂plays an important role in determining the best choice of sensor for your application. In this post we take a look at how the demands on sensors vary depending on the measurement environment.

If you’re measuring in a laboratory environment you’ll need accurate andtraceable measurement, and it’s also worthwhile to think about how traceability will be maintained. In these environments it makes sense to invest in a device with exchangeable measurement probes or modules. Other options could include field adjustment against a calibrated handheld device or with calibration gases. Labs are also home to a variety of different chemicals, so chemical durability for both the sensor and the enclosure is important. In life science labs in particular, decontamination might also be a factor that needs to be addressed.VaisalaIndigo series transmitters有一个可交换的GMP252 CO₂measurement probe并随身携带校准证书和IP65级的住房。该单元可以耐受最常见的消毒剂以及过氧化氢，这通常用于去污染程序。可交换的探针通过最大程度地减少校准停机时间来有助于保持可追溯性。

在公共场所您需要需要最小维护的传感器，并且能够在24/7全天候占据的环境中运行。任何维修都应直接，因为训练有素的人员可能无法提供。这些产品也应该不引人注目，并具有防篡改的外壳。VaisalaGMW80-series transmitters满足所有这些要求。关键功能包括：

• Accurate CO₂24/7全天候占用空间的测量
• Long operational lifespan of over 15 years
• Long-term stability:
  • co₂：±15 ppm + 2％阅读/5年
  • RH：±2％RH/2年
• co₂，相对湿度（RH）和温度（T）测量单个设备
• 非常简单的维护借助现场交换CO₂模块和湿度传感器
• Accurate RH+T measurement together with CO₂due to低自热

对于需要高测量精度的绿色建筑物和其他苛刻的环境，我们提供Vaisala GMW90系列, which features:

• 1000 ppm的CO的精度高达±50 ppm₂，满足LEED要求的要求
• 五年校准间隔和校准的三个不同选择
• Easy adjustment against reference gases or aVaisalaGM70 handheldunit
• User-friendly display shows you what you are doing during service
• 滑动前盖可轻松维护

选择用于测量CO的传感器₂concentration inoutdoor environments是整个建筑物最重要的之一，因为它所需的测量值用于控制建筑物的新鲜进气口。对于这种类型的应用程序，Vaisala提供了GMP252发射器，该发射器专为要求高湿度环境而设计。

Installation

壁挂传感器应该是安装at head height in a representative location and not behind a cupboard, in the ceiling, or close to an air inlet duct. It also pays to think about what’s behind the wall too. For example, if there’s underpressure in the room the sensor will be pulling in air from within the building’s construction, meaning you’ll end up measuring something completely different than the room conditions. In these cases, if there are leaks you may need to seal the cable feedthroughs.

另一个常见的错误是在彼此之间安装两个测量设备。这实际上不是CO的问题₂传感器，但是如果您在CO的顶部安装湿度或温度传感器₂传感器，CO的热量₂传感器的光源会扭曲测量结果。

校准

When it comes to maintaining your transmitter equipment,a handheld reference instrument like the Vaisala MI70可以非常有用，因为它可以使调整发射器更快，更容易：只需插入服务电缆，并且使用单个按钮按下您可以调整发射器以读取与参考仪器相同的读取器。请记住，人们是CO的最大来源₂，因此，不要直接呼吸到要校准的参考探针或传感器上。这听起来可能很明显，但是它一直都在发生！

It’s also important to adjust the pressure settings of your instrument. Because CO₂以百万分零件测量，将传感器校准为一定的气压水平或高程。安装仪器时，请确保您进入了正确的海拔高度以确保准确的测量。更重要的是，如果您通过对手持设备进行调整固定仪器来进行现场调整，则应确保两个设备都具有相同的压力或高程设置。

了解有关我们如何帮助您的更多信息with your HVAC measurements or联系我们for more information.