If you purchased the Optical DO Probe prior to January 2015, the percent saturation setting has a range of 0-100%. This range can be expanded to measure between 0-300%. The process includes paying an upgrade fee and sending the probe to Vernier for a few weeks. This upgrade includes parts and labor required to expand the percent saturation setting range to 0-300%, installment of a new Optical DO Probe cap, and recalibration.
If you have a PO number or other payment method available, let us know so we can authorize the upgrade. If you prefer, please let us know who to contact at your school that can process the upgrade fee.
For more information or to upgrade your Optical DO Probe, please contact Vernier Technical Support at 888-837-6437 or support@vernier.com