Pentair IntelliFlo VS+ SVRS Over Voltage Alarm

Parker Conley • Applies to: Pentair IntelliFlo VS+ SVRS

Pentair IntelliFlo VS+ SVRS Over Voltage Alarm

The over voltage alarm on the Pentair IntelliFlo VS+ SVRS has two distinct causes: excessive incoming supply voltage from the utility, and back-EMF generated when an external water source forces the pump impeller to rotate while the drive is off. Both conditions generate excessive voltage on the drive's internal DC bus.

How the Over Voltage Alarm Works

Per the manual's Alerts and Warnings section: "Over voltage: Indicates excessive supply voltage or an external water source is causing the pump and motor to rotate thereby generating an excessive voltage on the drive's internal DC bus. The drive will restart 20 seconds after the over voltage condition clears."

The alarm LED on the control panel will be lit when this condition exists. All control panel buttons are disabled until the alarm is acknowledged with the Enter button. Once the fault condition is resolved, press the Reset button to clear the alarm.

Power Out Failure (Related Condition)

The manual also describes the related "Power out failure" condition: "The incoming supply voltage is less than 170 VAC. The drive faults to protect itself from over current. The drive contains capacitors that keep it powered up long enough to save the current run parameters. If power is restored during this process, approximately 20 seconds, the drive will not restart until completed."

If power is restored within the approximately 20-second capacitor hold period, the drive will not restart until the parameter-saving process completes. Do not interpret this delay as a fault; the pump will resume normal operation once the process finishes.

System Pressure Warning

CAUTION: The IntelliFlo VS+ SVRS is capable of generating system pressures up to 50 PSI. Installers must ensure that all system components are rated to withstand at least 50 PSI. Over-pressurizing the system can result in catastrophic component failure or property damage. (Source: Pentair IntelliFlo VS+ SVRS Installation and User's Guide)

Corrective Actions

Excessive Supply Voltage

Check voltage at motor terminals and at the meter while the pump is running.
Check line voltage; if less than 90% or more than 110% of rated voltage (230 VAC), consult a licensed electrician.
Check for loose connections and tighten any loose wiring connections.

External Water Source Rotating the Impeller

If an external water source (such as gravity-fed flow from a spa or elevated water feature) is causing the pump motor to rotate while the drive is unpowered, this generates back-EMF on the drive's DC bus and triggers the over voltage fault. To resolve:

Identify and eliminate the source of passive water flow through the pump when it is not running.
Install appropriate valving to prevent back-flow, noting that check valves should not be installed on the suction side of a system protected by SVRS.
Consult a licensed electrician if the voltage condition cannot be identified.

CAUTION: Never open the inside of the drive motor enclosure. There is a capacitor bank that holds a 230 VAC charge even when there is no power to the unit. (Source: Pentair IntelliFlo VS+ SVRS Installation and User's Guide)