Sensaphone CELL682 - Manual (Page 44)

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Cell682 User’s Manual
In a Fill application, the Lag and Pumps-Off floats would change posi-
tion as shown below:
Fig 2. Float positions for a Fill application
In this case, the pumps are attempting to keep the well full. When the well is full
all three floats are closed. If the level drops below the Lead float, then the first
pump will turn on. If the level rises above the Pumps-Off float then the pump will
turn off. If the level continues to fall below the Lag float, then the 2nd pump will
turn on. Both pumps will remain on until the Pumps-Off float closes. If only one
relay output is set to pump-control mode, then simplex control is performed. In
Simplex mode only the Lead float (Dry Contact #6) and Pumps-Off float (Dry
Contact #8) are required. Either output relay can be used in simplex mode.
how it works—analog leVel sensor
When performing pump control with an analog level sensor, the Lead, Lag, and
Pumps-Off levels are programmed into the Cell682 software. The unit then
measures the actual level on Analog Input #6 and turns on the appropriate relay
outputs. If both outputs are set to Pump Control mode, then alternating duplex
control will be performed. If only one output is set, then Simplex control will be
performed. The analog level sensor must be a 4–20mA transducer that is selected
and calibrated based on the depth of the well. The specified output of the trans-
ducer must be entered into the Table Range settings for Analog Input #6.
installation recoMMendations
Be sure to install and wire the Cell682 and associated equipment in accordance
with all local codes and regulations. Adhere to Standard Practice/Best Practice
policies when installing and wiring any control system. Be sure to include hand-
operated switches to disconnect power on all pumps/equipment to insure worker
safety when installing and servicing equipment.