Xylem 19 001 251 R3 Floboy VFD Pumping System - Manual (Page 24)

20
reference to set point). There is a time delay of
60 seconds, before the station faults that is
designed to give the system time to adjust the
pressure to below this point. These values might
vary on your station.
Based on the values above, if the discharge
pressure remains 15 PSI above the set point for
longer than one minute, the station shuts down.
The red station fault light on the station comes on,
and the display indicates a “high pressure Safety”.
NOTE: At this point, shut the station down, and
determine what the problem is. Consult the
Troubleshooting section of this manual for
assistance.
To clear the fault, press the Reset control (F5).
Low Inlet Pressure
This optional safety is usually used on flooded-
suction booster pump applications.
Normally, a pressure switch monitors the inlet
pressure on the "suction" side of the pump. This
switch is located in a box on the lower left side of
the control cabinet. The switch is used in
conjunction with a relay to inform the controller
that it is unsafe to run. Setting the low inlet
pressure condition is accomplished by physically
adjusting the pressure switch. There is a 20
second time delay in the PLC.
Once the inlet pressure drops below the switch
pressure setting, all pumps shut down after a 20
second (adjustable) delay. The red station fault
light comes on, and the display indicates a "Low
inlet Pressure Safety”.
WARNING: Low Inlet Pressure – Station
Shutdown Hazard
At this point, shut the station down, and
determine what the problem is. Consult the
Troubleshooting section of this manual for
assistance.
Failure to follow these instructions could result in
serious personal injury or death, or property
damage.
There are two dials on the pressure switch. The
one on the top is the correct one to adjust. Turn
clockwise to increase the pressure set point,
counter-clockwise to decrease.
CAUTION: Delta Pressure Setting Hazard
Do not adjust the bottom dial. This is a delta
pressure setting, and is not used. This dial must
be adjusted fully counter-clockwise (0 position). If
you are having trouble with your pressure switch,
always verify that this dial is in the 0 (fully
counter-clockwise position) before adjusting the
top dial.
Failure to follow these instructions indicates a
potentially hazardous situation, which, if not
avoided, may result in property damage.
CAUTION
: Minimum Pressure Setting Hazard
The pressure setting is based on the minimum
inlet pressure that the pump can safely operate.
Do not lower the pressure switch setting without
consulting the factory
.
Failure to follow these instructions could result in
serious personal injury or death, or property
damage.
Loss of Prime
This optional safety is usually used on end-suction
centrifugal pump applications.
A level probe is placed in the suction piping at a
predetermined level. This probe works in
conjunction with a relay to inform the controller
that it is unsafe to run. Fault usually signifies a
malfunctioning foot valve.
After a few seconds, all pumps shut down. The red
station fault light comes on, and the display
indicates a "Loss of Prime fault"
NOTE: At this point, shut the station down, and
determine what the problem is. Consult the
Troubleshooting section of this manual for
assistance.
To clear the fault, press the Reset button.
CAUTION
: Equipment Damage Hazard
Do not attempt to bypass this safety, as pump
damage will occur.