Watts Pure Water PWR4021 Series, Installation, Operation And Maintenance Manual

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APPENDIX A. CONTROLLER PROGRAMMING: PARAMETERS EXPLAINED
Parameter Value Range Example
Input Switch Behaviors
Tank Level Switch de-Bounce Seconds 2.0
This specifies the time that the tank switch must be closed or open before the controller accepts it as a valid condition. This helps to prevent
nuisance tripping of the RO especially in small or turbulent tanks
Pressure Switch de-Bounce
Seconds 2
Pretreat Switch de-Bounce Seconds 2
This is the time that the pretreat switch must be OPEN before the controller accepts it as a valid condition. The function is to prevent nuisance
tripping of the RO especially in small or turbulent tanks
Pump/Inlet Solenoid Behaviors
Pump start delay Seconds 10
On RO start-up, after the tank switch opens, the inlet solenoid valve is energized. When the inlet pressure switch closes this begins the “Pump start delay”. If the pressure switch remains closed,
the pump will start after 10 seconds.
Inlet Solenoid stop delay
Seconds 1
This value sets the delay for the inlet solenoid valve to be de-energized following the de-energizing of the motor on Tank Full RO shut down. This prevents the pump from operating against a
closed suction as the pump spins down. Time values greater than 1 or 2 seconds may require an inlet valve that will operate with 0psi differential pressure.
Low Inlet Pressure Behaviors
Pump start retry interval (restart delay after LP fault) Seconds 60
When the inlet pressure switch opens, the controller de-energizes the motor and the inlet solenoid valve remains open. The controller will continue to monitor the inlet pressure switch. After the
switch is closed for the duration of the “Pump start retry interval” the motor is re-energized.
Low pressure fault shutdown, # of faults
Faults 5
Low pressure fault shutdown, time period to count faults Minutes 10
Low pressure fault shutdown, reset after shutdown (0 value = no restart) Minutes 60
These three values work together to determine how the RO handles Low Pressure conditions. The first two values, “# of faults” and “time period to count faults”, sets the limit for the number of
low fault conditions over time that are required to place the RO in “Low Pressure Fault Shutdown”. The third value sets the duration of the “Low Pressure Fault Shutdown” which is the period
that the RO will remain idle before trying to restart. The purpose of the Low Pressure Fault Shutdown is to prevent an RO from turning OFF/ON repeatedly without any limit.
Low pressure timeout fault
Seconds 60
If the inlet valve is open, but the pressure isn’t sufficient to close the inlet pressure switch, the RO would run indefinitely on line pressure. This value sets the time limit for the RO to operate with
the inlet valve open with Low Pressure as indicated by an Open inlet pressure switch before a Low Pressure Fault is added to the counter above.
Flush Behavior
Time from last flush before Flush on Shutdown Minutes 15
Minimum operation before Flush on Shutdown Minutes 60
Flush duration on Shutdown Seconds 60
Periodic Flush interval Minutes 60
Periodic Flush duration Seconds 30
Unit Idle Flush interval Minutes 0
The Unit Idle Flush Interval sets a time after which the RO will start-up and run in the flush mode. This is disabled by default because of the danger of over-flowing a tank if not properly imple-
mented. It is intended for environments where leaving the RO idle for long periods would invite bio-fouling. (0)=disabled
Unit Idle Flush duration
Seconds 0
Sets the duration of the Idle Flush. (0)=disabled
Timed Manual Run - Duration of Manual Run Minutes 5
Timed Manual Flush - Duration of Manual Flush Minutes 5
Conductivity Probe Sample Rate Seconds 2
Conductivity Shutdown (0)=disabled Minutes 0