FCS Sentinel 2, Руководство пользователя

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4.16 PRV C
ONTROL METHOD AND
S
ETTINGS
Sentinel2 provides 2-point pressure control; It is used to switch the output pressure for
the PRV between either a High or Low pressure setting, with the needle valve of the
pilot controlling the gradual downstream pressure changes between any transition in
the target pressure.
The target pressure (either High and Low) is set in Sentinel2 using a pressure profile
table, of which two types exist: Time control and Flow control.
An area within the Control Settings defines
which pressure profile tables will be used.
The installer should enable one or both of the
settings, as required.
Note: If neither of the control settings are enabled the unit behaves as if PRV control is
disabled; the PRV actuator setting remains fixed.
4.16.1 Setup of pressure control using a Time profile
To use a pressure profile that is based on
time, tick the “Time control” option.
(With the “Flow Control” box un -ticked,
flow does not participate in control
decisions, but is still logged).
… A “Safety Override” panel appears when
time control is exclusively selected. (See
section 4.16.2)
… A “Time Control” table will also appear.
Currently (in the illustration), the table is
blank; there are no entries visible.
To enter a line into the table, click on
the “+” button.
… A new line is added, which can be
edited with the required settings.
(The table has a capacity of up to 32 lines).
The Time Control pressure profile can be built
as a table of days, times, and a choice of the
High or Low setting.