Underwriters Laboratory Standards UL 1778 - UPS Equipment para 19.4 and UL 1741 - Inverters, Converters, and Controllers for Use in Independent Power Systems para. 20.3 state " A metal-to-metal piano-type hinge is useable as a means of bonding a door for grounding."
Is there a resource or standard practice for calculating the number and size of batteries for large UPS battery bank installations to accomplish desired ridethrough time, cycling requirements, voltage regulation, frequency regulation, etc.?
