stannah 420 this unit works fine it goes up to top and stops it will go back down and stop as it is supposed to but when it is stopped it beeps I have changed both batteries and checked the charger it seems to be working as it should is there something im overlooking voltage on batteries hold between 25.40 and 26.00 volts

Kevin E. Cunningham, February 2019

You are loosing contact at the bottom. Try moving the stop so it stops further up. Also clean the contact strip with WD-40.

Tom Mac, September 2020