WP440L-Series Reverse Osmosis System
Installation Instructions and User Manual
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The I/O Expander board adds 2 relays and 1 switch input. The operation and programming of the 2 relays is described in
the installation section.
Relay 1 can be used to control a re-pressurization pump when relay 1 of the expander board is configured to operate an
aux relay. In this mode, this relay will be energized as long as the tank low input is not active. When energized, the relay
supplies power to the re-pressurization pump.
When the tank low input has been active for 5 seconds, the auxiliary output will turn off. The alarm lamp will light and the
TANK LOW warning message will show on the display. When the tank low condition clears, the TANK LOW 99 warning
message is displayed. The number is the delay in minutes before the auxiliary relay will energize.
For boost pump operation, when the tank low input has been active for 5 seconds, the boost pump output will turn off, the
RO unit will shut down, the alarm lamp will flash and the audible alarm will sound. TANK LOW shutdown message will show
on the display. When the tank low condition clears, the TANK LOW 99 shutdown message is displayed. The number is the
delay before the RO unit will restart. The shutdown can be manually reset by pressing the Alarm Silence/Reset button twice.
Relay 1 can be used to control a boost pump when the expander board is configured to operate relay 1 as a boost pump
relay. This relay will operate the same as the inlet solenoid relay. This option is used to directly operate a boost pump up to
1HP.
When relay 1 or relay 2 has been programmed to operate as a divert relay, the relay will energize when the TDS /
Conductivity exceeds the TDS / Cond Limit Set-point. This will occur as soon as the reading exceeds the limit, there is no
delay. When the reading drops below the limit and stays below the limit continuously for 5 seconds, the divert relay will turn
off.
When relay 2 has been programmed to operate as an alarm relay, the relay will energize whenever a warning or alarm
condition occurs. The relay will remain energized as long as the warning/alarm condition is active.
ADJUSTMENTS
Refer to illustration 3 for adjustment location. To calibrate the TDS / Conductivity, place the cell in a known standard
solution. Adjust the span adjustment for the correct reading. If the cell is installed, the unit can be calibrated by taking a
sample of the permeate water and testing it with a known, good meter. Adjust the span control until the reading matches
the meter.
Note: If the TDS / Cond range is changed, the unit must be recalibrated AND some components
may need to be changed.
The display contrast can be adjusted for best viewing by adjusting control R3. This control is located toward the upper right
corner of the board, just to the left of the cell connector.
I/O Expander
Auxiliary Output
Tank Low
Boost Pump Output
Divert Output
Alarm Output
TDS / Conductivity Calibration
Display Adjustment
