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Pumps

VFD Faults

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Low DO / Aeration

SCADA

SCADA Alarms

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Process Upsets

Effluent / Compliance

Randy
Randy AI
Troubleshooting: Pump Problems
Randy
Hey, I'm Randy - let's figure this out together. You selected Pump Problems. Can you tell me a bit more about what's happening?

For example: Is the pump not starting at all, is it running but not producing flow, or is it tripping out on an alarm?
User
Pump 2 won't start. The HOA switch is in Auto and it shows a fault on the MCC panel.
Good info. A fault on the MCC panel is our starting point. Let's work through this:

Step 1: What fault code or indicator are you seeing on the MCC? Common ones are:
- Overload / thermal fault (OL)
- Ground fault
- Short circuit
- Phase loss indicator

If it has a VFD, what's the fault code on the drive display?
'
The overload relay light is on. We had a power fluctuation about an hour ago.
That makes sense - a voltage fluctuation can cause an overload relay to trip even if nothing is mechanically wrong with the pump. Here's your path:

[X] Step 2 - Reset the overload relay:
Locate the overload relay block (usually a blue or black module on the starter). Press the reset button. Wait 10 seconds.

Step 3 - Check voltage before restart:
Before you start the pump, verify you have balanced three-phase voltage. A single phase dropout can cause the motor to draw too much current and trip immediately again.

" Step 4 - Test start in Manual mode:
Briefly bump the pump in Manual (HOA) to confirm it starts. If it trips again quickly, we may have a mechanical issue or undersized OL heater.