If you are looking for the technical manual or specific wiring instructions, you can access these official resources from Amada Weld Tech CY-210B Addendum (Revision C) : Provides detailed instructions for Forge Weld Operation
Open the back compartment. Insert (do not use carbon-zinc). Observe polarity (+/-). If the display shows “Lo” immediately, your batteries are weak or reversed. weltouch cy-210b manual