Many duplex pump applications require Sequence On – Simultaneous OFF operation with three float switch inputs and alternation of which pump is turned on first. The two loads are energized sequentially when the LEAD & LAG switches close, but remain on together until the OFF switch is opened. Normally, this is all done with a separate alternating relay, a control relay and two auxiliary contacts. Macromatic Duplex Controllers combine the function of these individual components in one plug-in product utilizing an 8-pin sock - et. This reduces the cost of the control panel by saving space, reducing the number of components and minimizing assembly labor. A low profile, three-position switch is provided to alternate the two loads as normal or lock the relay to always operate the same load first each time.
