You've evaluated the measurement demands of your application, specified the sensor requirements, and purchased the new device. But you're not finished yet. You still have to commission the sensor. In this phase, you're simply ensuring the sensing device is functioning and will continue to do so for an appropriate length of time. Here are some ideas on how you can make the process go as well as possible.
Covering All the Bases
All too often, this step is overlooked, even though it is a key part of the installation process. The challenge here is that there are no universally accepted guidelines to follow. So I'll review seven steps that have served me well over the years. The essential tasks involved in commissioning a sensor can be summarized as follows:
- Ensure the sensor is installed properly, with all its inputs and outputs complete.
- Verify the unit is mounted properly. For example, if you are working with a device such as an imaging camera or infrared thermometer, be sure it's aimed at and focused on the proper target. When appropriate, make sure the device is connected to the sample and reference taps.
- Ensure the sensor is powered properly (e.g., loop current, 24 VDC, 115 VAC, or 240 VAC) and is delivering the correct signal (e.g., analog current or voltage, digital, correct format, or opto) to the correct device or system.
- Verify support services, such as air purge or cooling, are functioning as needed.
- Be sure installation details and up-to-date manuals and support documentation are readily available for the maintenance staff.
- Make certain the sensor is logged into the control or monitoring system and identified correctly, as specified in the system coding scheme.
- Ensure support personnel understand the equipment, its installation, and maintenance needs and are capable and outfitted properly to maintain the device.
The actual details of each installation depend a great deal on the type of sensor and how it interfaces with the object of measurement and the monitoring or control system to which its output is delivered.
If you need help establishing calibration intervals, check the resources at NCSL International and the Integrated Sciences Group recommendations for calibration intervals and available free software. Both organizations, among others, offer excellent training programs.