Pentair FLECK 3150 NXT, Руководство по установке

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Installer manual Fleck 3150 NXT/NXT2 - System sizing
Ref. MKT-IM-010 / C - 18.10.2019 33 / 182
To calculate slow rinse duration:
The volume of water to be used for slow rinse is given in the resin manufacturers
specifications. Generally speaking, it is advised that between 2 and 4 BV of water is
used to perform the slow rinse after brine draw. The slow rinse cycle allows brine to be
pushed slowly through the resin bed, allowing the resin to be in contact with brine for
sufficient time and therefore to be regenerated.
Refer to the injector curve at the common working pressure to determine the slow
rinse duration.
T
slow rinse
= (N
BVsr
x BV) / Q
SR
with:
T
slow rinse
: slow rinse duration [min]
N
BVsr
: number of bed volume for slow rinse
BV: bed volume [L]
Q
SR
: injector slow rinse flow rate [L/min]
To calculate fast rinse duration:
The fast rinse is aimed at eliminating an excess of salt in the resin bed and also
recompacting the resin in the tank.
Depending on the valve type, the fast rinse flow rate is controlled by the DLFC or it has
about the same flow rate as in service. The fast rinse velocity can be the same as the
service velocity, and the volume of water to be used for the fast rinse is generally
between 1 and 10 BV depending on the salt dosage.
T
fast rinse
= (N
BVfr
x BV) / Q
DLFC
with:
T
fast rinse
: fast rinse duration [min]
N
BVfr
: number of bed volume for fast rinse
BV: bed volume [L]
Q
DLFC
: drain line flow controller size [L/min]
To calculate the refill duration:
The refill flow rate is controlled by the refill controller (BLFC). The relation between the
BLFC size, the tank size and the resin volume is given in the valve specifications.
To calculate the refill duration:
T
refill
= V
WB
/ Q
BLFC
with:
T
refill
: refill duration [min]
V
WB
: Volume of water to be refill to prepare the
brine [L]
Q
BLFC
: BLFC size [L/min]