Adding a new piece of equipment or specialized instrumentation to your facility has the potential to add significant value to your product. Whether it be in the quality assurance or manufacturing process, adding a new instrument may save the company time, money, and increase the overall quality of your product. However, adding a new method of analysis of your product requires learning new testing procedures and developing new testing parameters. This learning curve may be the primary focus of the operator, but other tasks are important to keep in mind while adjusting to your new instrument. Tasks such as general maintenance and calibration checks should be practiced regularly to ensure the accuracy of your instrument as well as preserving the longevity for years to come.
For operators using the moisture specific Vapor Pro ® line of instruments, routine purging of the internal tubing is recommended. When heating samples on a daily basis within the Vapor Pro®, there is a good chance that volatilized/re-condensed material will remain deposited on the sensor of the instrument. Making sure the sensor and tubing is void of any residue ensures accurate results. This is completed by filling a sample vial with isopropyl alcohol (IPA) and manually moving the bottle transport in to the oven chamber. Since IPA has a relatively low vapor pressure, it is recommended that the temperature of the instrument be set below 80 °C. Once the transport has moved into the oven, the IPA will be pushed through the flow path allowing the fluid to flush the sensor as it passes. Be sure the instrument is fitted with brass outlet port fitting to allow for proper drainage. It is helpful to place an empty vial under the outlet port fitting to catch the outflow during the purge. Leave the clean IPA vial in the instrument for approximately 30 seconds then manually move the transport out. Once this is complete the sensor will be saturated and it could take 15-20 minutes to return to proper testing conditions. Arizona Instrument LLC recommends this be done a minimum of once a week or as needed (depending on the type of material). For a sample that volatilizes more readily, this type of cleaning may be needed more frequently.
When utilizing the moisture specific Vapor Pro® line of instruments, the best check to verify the accuracy of your instrument is to run a ‘RH Sensor Cal’ test. This requires NIST (National Institute of Standards and Technology) traceable 1000µg capillary and deionized water. To run this test, select the preprogrammed ‘RH Sensor Cal’ test and allow the instrument to heat up to 215 °C. Gently break the surface tension of the deionized water with the capillary and water will fill the tube by capillary action. Gently wipe any excess water droplets with your finger (Avoid cloth or tissue) and place filled capillary into a sample vial. Seal the vial and place horizontally into the transport and begin running the test. The test should take no more than 4-6 minutes and should yield 1000 µg ± 50 µg. If the test results are not within this range, run a second test. If the results are still not acceptable, call our customer service department for troubleshooting details.
Following a maintenance and calibration schedule for your instruments may seem like an extra step in your busy day, but is well worth it in the long run. This will optimize your instrument’s performance and give you peace of mind that your instrument is working properly and accurately. This will reduce downtime, and ensure the quality of your product.