Technical Bulletins relating to WMT 6 can be viewed and downloaded by clicking on the link below.
Change to WMT Charger Specification. TB-12-007
Changes were made to the WMT to improve the reliability of the internal power regulation. This required the minimum operating voltage to be increased from 18 V to 20 V. When this was made the WMT charger kit (650-0043) was also updated to use a 24 VDC PSU.