Why won’t my OHAUS Scout balance show negative values on LabQuest or Logger Pro?April 24, 20170 It will work; however, you must use the TARE key instead of the ZERO key. The TARE key is available on the following OHAUS Scout models. (OHAUS Scout Pro models continue to use the ZERO key.) OHAUS Scout® 220 g (OHS-222) OHAUS Scout® 420 g ... Continue Reading →