I have 15 2bdrm units draining into a 4'diamater x 8' deep sump. I have a duplex pump system with 4 floats. They are all pump down switches. With the lower float pointing up to arm the system, then another float to turn on the pumps. Then another float just above that float and I am not sure if it is back up incase the first float fails or override in case a pump fails. I pumped down just far enough to keep the lower float pointing up. When I manually pointed the next switch up the pumps activated as they should. Again I pumped down so the lower switch pointed up, and with the next switch hanging down, I manually turned the third switch up and nothing happened. I disconnected the float from the 2 wires that go to the control panel and with a tester on both wires to the switch when I pointed it up it completed the circuit so the switch is ok. Then I tested the 2 wires that go to the control panel and the circuit was complete . The alarm float works fine and both pumps work fine when I use the manual switches. Am I checking the right way to find out about the third switch?

The bottom float is the "turn off" switch. The next one up is the one that activates the primary pump. The third one activate BOTH pumps if the water level keeps rising for some reason, and the fourth one is activates and alarm and any other actions if there is a failure to keep up with the water flow. With the bottom one inverted, you invert the next one up to turn on a pump (the pumps will alternate as the primary one after each operation), then you invert the third one to turn on both pumps. Inverting the upper one should acivate the alarm system.