Xylem 19 001 251 R3 Floboy VFD Pumping System - Manual (Page 23)

19
CONTROLLER BYPASS OPERATION
Overview
This is an abnormal operating mode and would be
used if the controller was not operable and there is
need to irrigate.
WARNING: Controller Bypass Hazard
This mode of operation should be used as a last
resort.
Constant operator monitoring is
REQUIRED when this mode is used. No safeties
function in controller bypass, and damage to your
piping or property could occur.
Failure to follow these instructions could result in
serious personal injury or death, or property
damage.
System Operation (performed in order)
All Individual Pump switches: OFF
Using the VFD keypad located below the
pump switches on the door, Set the
following parameters:
1102 - EXT2 (7)
3018 - Not Sel (0)
4011 - Verify set point
4023 - Verify Min Speed
Pump 1 switch: ON
Verify operation before leaving
unattended.
SYSTEM SAFETIES
Overview
The program in the PLC protects the system by
shutting down in either of the “Auto” or “Manual”
Modes of operation if it detects any of the following
problems:
Fault Reset
All faults are cleared by pressing the Reset control
(F5) on the HMI, or by re-arming individual pump
faults by turning the individual pump switch to the
OFF position, and then back ON.
Table 1: Safeties
Low Discharge Pressure
The pressure transducer located in your station
discharge line communicates the downstream
pressure to the controller. The controller monitors
downstream pressure to determine if the pressure
is below the allowable range.
The standard program defines low-discharge
pressure as being 80% of set point pressure. This
setting is in gage pressure, not in reference to set
point. There is a time delay of 300 seconds
(adjustable) before the station faults that is
designed to give the system time to build pressure
beyond this point. The values might vary on your
station.
If the discharge pressure remains below the Low
Pressure set point for longer than 60 seconds, all
pumps are shut down. The red station fault light on
the station comes on, and the display indicates
that a "Low Discharge Pressure Safety" has
occurred.
This fault does not automatically reset. To clear
the fault, press the Reset control on the HMI.
If the pump station is simply unable to keep up
with the demand, shut the station down, and
determine the nature of the problem. Consult the
Troubleshooting section of this manual for
assistance.
High Discharge Pressure
As with the "Low Discharge Pressure" fault, the
controller monitors downstream pressure to
determine if the pressure is out of range, or above
the allowable limit.
The standard controller program defines high-
discharge pressure as being 15 PSI above set
point pressure (set in gage pressure without
Alarm or Fault
Low Discharge Pressure
High Discharge Pressure
Low Inlet Pressure (Optional)
Loss of Prime (Optional)
Low Level (Optional)
Individual Pump Faults
VFD Fault