Normal Operation (Both Power Feeds Good)

Primary Circuit
The primary circuit functions like a textbook four float alternating lift station. It uses off, lead and lag float switches to control the tank level. The pumps alternates every time one of the off floats is reached. As long as the tank level stays within the normal floats levels, the system will use the primary circuit to regulate the tank level, alternating the pumps every time the off floats are reached.

Secondary Circuit
The secondary ultrasonic sensor provides redundant monitoring of the tank level. If the primary circuit cannot handle the water intake due to failure, the secondary circuit will latch both pumps on for a full tank pump down until the ultrasonic off relay is activated. The high alarm strobe will be latched on until an operator presses the alarm-reset push button. Additionally, there will be a high alarm signal sent to the control room when the secondary pump down is latched. If the tank starts to fill again, the ultrasonic sensor will manage the level and keep sending an alarm signal to the control room. This condition can be only be fixed by an electrician visiting the site to troubleshoot the problem.

Primary Phase or Voltage Bad

Primary Circuit
If a phase on the primary circuit goes off, the primary phase monitor relay will turn off. Pump 1 will be disconnected to protect the pump (under all conditions). The primary and secondary control voltages will be sourced from Transformer 2 (maintaining both control voltages). However, the Pump 1 contactor will not operate. The Pump 2 contactor will operate as a textbook four float alternating lift station, being controlled by the float system.

Secondary Circuit
The secondary ultrasonic sensor will provide redundant monitoring of the tank level. If the primary circuit cannot handle the water intake due to failure, the secondary circuit will latch both pumps on for a full tank pump down until the ultrasonic off relay is activated. The high alarm strobe will be latched on until an operator presses the alarm-reset push button. Additionally, there will be a high alarm signal sent to the control room when the secondary pump down is latched. If the tank starts to fill again, the ultrasonic sensor will manage the level and keep sending an alarm signal to the control room. This condition can be only be fixed by an electrician visiting the site to troubleshoot the problem.

Secondary Phase Or Voltage is Bad

Primary Circuit
If a phase on the secondary circuit goes off, the secondary phase monitor relay and LED will turn off. Pump 2 will be disconnected to protect the pump (under all conditions). The primary and secondary control voltages will be sourced from Transformer 1 (maintaining both control voltages). However, the Pump 2 contactor will not operate. The Pump1 contactor will operate as a textbook four float alternating lift station, being controlled by the float system.

Secondary Circuit
The secondary ultrasonic sensor will provide redundant monitoring of the tank level. If the primary circuit cannot handle the water intake due to failure, the secondary circuit will latch both pumps on for a full tank pump down until the ultrasonic off relay is activated. The high alarm strobe will be latched on until an operator presses the alarm-reset push button. Additionally, there will be a high alarm signal sent to the control room when the secondary pump down is latched. If the tank starts to fill again, the ultrasonic sensor will manage the level and keep sending an alarm signal to the control room. This condition can be only be fixed by an electrician visiting the site to troubleshoot the problem.