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Model CD-2R REDUNDANT PUMP CONTROL - using two floats
This specification covers a complete automatic redundant pump control and alarm system responding to the ________________ level as shown on the plan drawings.
The controller shall be provided with two FS 90 float switches for differential level control of the redundant system. The high alarm float shall be positioned above the normal operating range of the primary control for the sensing of the high-level alarm. The second float shall be positioned at the Pump(s) Off level.
The controller shall incorporate a front panel LCD (liquid crystal display) that clearly indicates the active inputs/outputs and provides an operator interface for viewing and changing the integral timers. An off delay timer shall be keypad programmable from 0-5.00 minutes. When the High-level float contact closes, the controller shall energize a lead pump output. If the float switch remains closed, the controller’s internal 2nd pump on-delay timer shall expire and call for the second pump. The second pump start delay shall be adjustable from 0-99.9 seconds. The pump(s) shall continue until the process level reaches the Pump(s) Off float and its contact opens. At the end of the pumping sequence, the controller’s alternator shall advance to the next pumping sequence. The controller shall have provision for an external alternator selector switch which shall allow the selection of either a 1-2, Auto or 2-1 pumping sequence. The controller shall contain four relay outputs. Two outputs shall be used for pump control – wired in tandem with the primary control system’s control outputs. The controller shall contain an alarm output and alarm monitor relay output. The alarm output shall automatically silence and reset following the end of each pumping cycle. The controller shall accept an external alarm silence input. The controller shall be UL 508 Listed. The controller shall be a CONTEGRA CD-2Ra.