Duplex Alternating Delayed System (System 8) (Nxt2 Only); Multiple Valves, Parallel System With Standby Unit (System 9) - Pentair Fleck 3150 NXT Installer Manual

Installer manual Fleck 3150 NXT/NXT2 - Installation
Inlet
Valve
Tank
5.8.5

Duplex alternating delayed system (System 8) (NXT2 only)

This system works with 2 valves and a meter.
During normal operation, the controller of each valve displays the time of day and the volume of
water remaining. The remaining volume displayed drops with water consumption to reach zero.
When this happens, the valve in service books a regeneration that will start at the programmed
regeneration time. When the programmed regeneration time is reached, the valve in service
sends a signal to the valve in standby that moves into service position. Once the 2nd valve is in
service, regeneration of the exhausted valve starts. Automatic regeneration may be triggered by
either volumetric immediate mean or external dry contact.
Inlet
Valve
Tank
5.8.6 Multiple valves, parallel system with standby unit (System 9)
This system type may be used to build systems from 2 to 4 valves for NXT controller, 2 to 8 valves
for NXT2. Each valve must be equipped with a water meter.
One to three tanks in service (NXT) or one to seven tanks in service (NXT2) supplying treated
water, one tank in standby. The regeneration of an exhausted unit can start only after the unit in
standby has returned to service position. When the regeneration cycle is complete, the
regenerated unit will enter in standby. Standby on each tank is controlled by the relay on the NXT2
circuit board.
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Outlet
Meter
Check valve
Outlet
Meter
Check valve
Ref. MKT-IM-010 / F - 16.01.2023