48
Culligan® Series M2 Reverse Osmosis
48
Cat. No. 01023095
Setting
Measuring Device
Configuration
Feed Flow FFLOW
FM1
Wired to inlet flow meter on the mas-
ter GBE
Product Flow PFLOW
FM2
Wired to product flow meter on the
slave GBE
Intermediate Flow IFLOW
FM3
Wired to product flow meter on the
master GBE
% Recovery
= (FM2/FM1) x 100%
Feed TDS
TDS1
Wired to feed TDS on the master GBE
Product TDS
TDS2
Wired to product TDS on the slave
GBE
Intermediate TDS
TDS3
Wired to product TDS on the master
GBE
% Rejection
= (1.0 – (TDS2/TDS1)) x 100%
Table 5. Two-Pass RO instrumentation.
Duplex-Alternating RO Mode
The GBE RO controller controller is capable of coordinating the alternating operation of two RO units plumbed in paral-
lel. This operation mode is designed for situations where RO redundancy is desired. As long as both RO units remain
functional, the controllers will direct one of the units, called “Unit A,” to be in the “ready-to-run” mode for a one hour block
of time beginning at the top of the hour. During that one hour block, Unit A will produce RO water as long as the storage
tank is NOT full and as long as there is no pre-treatment-lockout condition in effect. During this first hour, Unit B will be in
standby mode. At the beginning of the next hour, control switches to Unit B and Unit A will switch to Standby. During that
second hour, Unit B will produce RO water as long as the storage tank is NOT full, and as long as there is no pre-treat-
ment-lockout condition in effect. The units will continue to switch over control at the top of each hour indefinitely.
For example, the master RO pumps on even hours (12:00 to 1:00, 2:00 to 3:00, 4:00 to 5:00, etc.), and the slave RO
pumps on odd hours (1:00 to 2:00, 3:00 to 4:00, 5:00 to 6:00, etc.).
If at any time while in duplex-alternating mode either Unit A or Unit B stops functioning, or enters an “error state” (for ex-
ample if the product TDS exceeds the maximum allowable product TDS level) then the other unit will take over operation
and will continue to operate as a single stand-alone mode until an operator clears the error on the first unit.
If at any time while in duplex-alternating mode the two units lose communication with each other (for example if the com-
munication cable is cut or becomes unplugged), then both units will switch into single stand-alone mode until communica-
tions are re-established and an operator instructs the units to return to duplex alternating mode using the GROC menu
screens.
In Alternating-Mode, each RO unit has its own GROC controller. A standard communication cable (P/N 01016327) is
used to connect the two GROC controllers together as shown in
and the units are plumbed as shown in
. It is necessary that each RO unit have its own independent storage tank level (or pressure) switch and that, if a
pre-treatment lockout system is to be used, that each RO have its own independent dry contact closure signal from the
pre-treatment system wired to the individual GROC controllers.
When either unit is the “running” unit, it operates as a single unit.
