The set point will only be locked in if the switch measures six readings
within the margin. This margin allows for some pressure variation as the
pressure stabilises, eg. some air still being purged from the system. A
setting of 20kPa is generally OK.
The IPG20 uses a paddle to detect flow. The paddle is held in the no-flow
position by an adjustable magnetic screw that is located in a port under the
electrical housing of the pump guard. If flow pushes against the paddle, the
paddle moves. The movement is detected by the pump guard and identified
as flow. Initially in a system that is not running or has all its valves shut there
will be no flow and the paddle will be in the off, or no flow, position. In order
to override this initial off state and allow the pump to start the pump guard
uses the start-up timer.
The timer ignores the initial off state of the paddle and allows the pump to
run for a settable time. As soon as flow is detected the start-up timer
terminates its run and hands control of the pump over to the paddle. The
start-up timer is adjustable from 0 – 240 seconds (0 – 4 minutes) in 1-
second increments. The value you enter will depend entirely on your
pumping system. For a fully primed system the start-up timer may only
require one or two seconds to establish flow. In a submersible bore pump
installation with a self-draining riser it may take several minutes to establish
flow past the paddle.
This timer must be set for sufficient time to allow the system pressure to
stabilise before the switch goes into learning mode. Allowance should be
made to fill any lines which may drain when not in use and to purge any air
from the system.
This timer must be set for sufficient time to allow the system pressure to
stabilize before the switch goes into learning mode. Allowance should be
made to fill any lines which may drain when not in use and to purge any air
from the system.
START UP TIMER
SET POINT MARGIN
RAMPING UP TIMER - Manual operation only
AUTO START AFTER TIMER – Automatic operation only
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