The amp hours describe the available capacity on a lead acid battery. The equation is broken down with the number before the Ah being divided by the hours printed on the battery. This yields the approximate power capacity the battery is able to maintain until it drains its power.
ABB offers. three-phase monitoring relays with selectable phase sequence monitoring. This provides the capability of ignoring phase. sequence conditions for applications, such as motors with forward and reverse rotation, where the phase sequence is. unimportant.
A mercury relay is a relay that uses mercury as the switching element. They are used where contact erosion would be a problem for conventional relay contacts. Owing to environmental considerations about significant amount of mercury used and modern alternatives, they are now comparatively uncommon.