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# LOW TDS PUMPS RUNNING LEAD AND LAG
01/26/2012 KTS
The Low TDS pumps were both running all the time, at a flow rate that one pump can handle on it's own.
Found contacts in LO_TDS_PMP rungs 001 through 005 relating to V-401B that seem unrelated to the Low TDS pump logic. V-401B is the permeate flow valve of RO train B.
The Lag pump has been running since the basin was at a high level. The reason is because the pump speed never dropped below the LO setpoint. This setpoint is used to stop the Lag pump call. This setpoint is currently set at 40. The two pumps were running at 60 to maintain 350gpm.Should change the setpoints to 65
Also, the Lag call was not dropping when the LO TDS Pump logic was stopped with the SCADA pushbutton. I made a change on rung 0019 to remedy this. So now if the process gets stuck again in the Lag run position it can be reset by going to OFF then to ON.