Pump keeps tripping — what to check
Short answer: The three usual causes are dry running (empty tank or air in the suction), overload (the pump working too hard), or a supply voltage problem. If the panel is tripping, it is doing its job — it is protecting the pump. So do not try to stop it tripping; find out why.
Start with what the panel is telling you
NXT series panels display an error, which identifies half the problem straight away:
| Display | Meaning | See |
|---|---|---|
| Dry run / DR | No water at the suction | Cause 1 |
| Overload / OL | Motor drawing excess current | Cause 2 |
| Under / Over voltage | Supply problem | Cause 3 |
| Phase fail | One phase missing on a 3 phase supply | Cause 4 |
| HP / LP | Pressure too high or too low | Cause 5 |
Cause 1: Dry running — the most common
The pump is not receiving water. Possible reasons:
- The feed tank has emptied
- Air in the suction line
- Foot valve choked or failed
- Inlet valve left closed
- Suction strainer blocked
Fix: check the tank level, prime the suction line and clean the foot valve. Full details in our dry run protection guide.
Cause 2: Overload — the pump is working too hard
The motor is drawing more than its normal current. Possible reasons:
- Choked cartridge filter — the most common by far. A blocked filter forces the pump to work much harder
- Membrane scaling — pressure has risen
- Discharge valve throttled — somebody has closed it partly
- Bearing failure — the pump runs hot and the sound has changed
- Overload setting wrong — the panel is set below the pump rating
Fix: change the cartridge filter first — that resolves around 60 percent of cases. Compare inlet and outlet readings on your pressure gauges.
Cause 3: Supply voltage problems
Very common in India, particularly in rural and industrial areas.
- Low voltage: the motor draws more current and overheats
- High voltage: stress on the windings
- Fluctuation: repeated tripping
Fix: measure the voltage with a multimeter — around 415V on three phase, 230V on single phase. If it is well outside that, a stabiliser or proper protection is needed. NXT panels have voltage protection built in.
Cause 4: Phase failure (three phase only)
One of the three phases has been lost. The motor tries to run on two phases and draws very high current — this is the leading cause of burnt motors.
Fix: check the MCB, fuses and incoming supply on all three phases. Sometimes one contactor contact has burnt out, so check that too. This work should be done by an electrician.
Cause 5: A pressure switch tripping
There are two types:
- Low pressure switch (₹546) — cuts out when inlet pressure falls, which happens with a choked filter
- High pressure switch (₹546) — cuts out when outlet pressure rises, which happens with membrane scaling or a closed valve
Fix: identify which one is tripping, then check the filter or membrane accordingly. Also verify the switch setting itself — sometimes that is what is wrong.
Cause 6: Level switch fault
There is water in the tank but the float has jammed, or the wiring has failed, so the panel believes the tank is empty.
Fix: move the level switch up and down by hand — the panel indication should change. If it does not, the switch or wiring has failed.
Cause 7: Wrong panel setting
The overload current is set below the pump rating. A 5HP motor draws around 7 to 8 amps, but if the panel is set to 5 amps it will trip every time.
Fix: set the panel according to the current stated on the pump nameplate. Have a competent electrician do this, or ask us.
Checklist — in this order
- Note what error the panel is showing
- Is there water in the feed tank
- How old is the cartridge filter — change it if over 3 months
- What do the pressure gauges read
- Is the pump hot, or does it sound different
- Measure the voltage
- Compare the overload setting with the pump nameplate
When to call an electrician
- A phase failure error
- Any burning smell or smoke from the pump
- Noise or sparking inside the panel
- Tripping continues after all of the above have been checked
If a new panel is needed, see Astero controllers — the full chart is in our selection guide.
Tripping still not resolved?
Send us the panel error, the pump HP and the symptom — we will help you work out what to check.
💬 WhatsApp par poochhein 📞 9910646957Frequently asked questions
Why does my pump keep tripping?
The usual causes are dry running, overload and supply voltage problems. The panel display normally indicates which one it is. Tripping is actually a good sign, because the panel is protecting the motor from damage.
Can I bypass the trip protection?
No. The protection exists to prevent the motor burning out. Running the pump with it bypassed risks destroying the motor, which costs many times more than the panel. Find and fix the cause instead.
What is the most common cause of an overload trip?
A choked cartridge filter. When the filter blocks, the pump has to work much harder and draws more current. Change the filter first, as that usually resolves it.
What happens during a phase failure?
With one of three phases missing, the motor tries to run on two and draws very high current. This is the leading cause of burnt motors, which is why the panel trips immediately. It should be investigated by an electrician.
What should the overload setting be?
It should match the rated current stated on the pump nameplate. Set too low the pump trips needlessly, and set too high the protection is meaningless. Have a competent electrician set it.