6.2.1b Lead-Lag Alternation
To wear evenly, the duty pumps alternate between lead and lag
designations. The PLC counts down the total time (Alternation
Delay Time) that a pump operates as the lead pump.
Once the alternation delay time reaches zero, the system stops
all pumps. Then, it switches the lead pump designation to a
different pump; the former lead pump becomes a lag pump.
KEY TERMS
System Pressure Setpoint: The system pressure that the
station is set to maintain.
Jockey (Pony) Pump: Designed for pressure maintenance
and low demands, it is the first pump to operate when
pressure drops below the setpoint.
Lead Pump: The lead pump turns on if demand exceeds the
capacity of the jockey pump. It varies its speed to meet
fluctuating demand. If it can’t meet demand, then the lag
pump is turned on to help.
Lag Pump: If the lead pump is at full speed and is still unable
to meet the system pressure setpoint, the lag pump is
turned on. Its speed does not vary—it operates at full speed.
It turns off (enters sleep mode) when the lead pump can
meet demand.
Sleep Mode: Pumps will stop pumping—enter sleep mode—
based on demand.
6.2.2 Additional Automation Features:
6.2.2a Automatic Filter Controls
• The controller will signal the filter flush valve to open based
on a signal from a PSID switch. There are also timer based and
manual filter flush controls.
• Automatically operated intake screen supply valve.
6.2.2b Remote Start
In addition to starting on pressure drop, the system can also
start via a remote signal from an external source, such as an
irrigation controller. The system will then operate automatically
to maintain the PSI Setpoint.
6.2.2c System Protections
The system will automatically Fault (shut-down) to protect the
system from the following occurrences:
• Low Level
• High Pressure, Low Pressure
• High Flow
• Low Flow
• Overload
• Underload
• Phase Loss
• Electrical Surges
6.2.2d Trend and Fault Data
The control system records and displays system operational
data, including flow rate, discharge pressure, motor amperage,
and system faults.
6.2.2e Remote Monitoring
Systems equipped with an ethernet switch and cellular modem
enable users to control and monitor the system from any web
browser.
Precision Pumping Systems
•
GoPPS.com
•
6515 Business Way, Boise, ID 83716
•
208.323.5300
These systems can also automatically send faults and warnings via
email or text message.
1. Visually inspect the pump station for any apparent abnormali-
ties such as loose wires, loose fittings, and for any damage.
NOTE: Notify Precision Pumping Systems immediately if
anything abnormal is found.
6.3 Start-Up
2. Turn the HOA (“Hand”, “Off”, “Auto”) switches on front of the
panel to the “OFF” position.
3. Turn on Main Disconnect. Wait for the station to completely
power on.
4. Turn the HOA switches on the front of panel to the “AUTO”
position.
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