Motorised vs solenoid dosing pump — which to choose
Short answer: A solenoid pump covers 6 to 10 LPH — economical, compact, and adequate for around 90 percent of RO plants. A motorised pump starts at 25 LPH — more expensive, but built for heavy continuous duty.
Put simply: if your dosing falls within 10 LPH, take a solenoid and save the money. Above 25 LPH there is no alternative to motorised.
How each works
Solenoid — driven by an electromagnet
An electromagnet pushes the diaphragm and releases it. Each push is one stroke. You can set both strokes per minute and stroke length.
Advantages: compact, light, economical, very low power consumption, no rotating parts.
Limitation: the coil heats up under prolonged heavy duty, and capacity is limited.
Motorised — driven by a motor and gearbox
A motor drives the diaphragm through a gearbox. It can run continuously, 24 hours a day.
Advantages: high capacity (up to 400 LPH), continuous duty, more robust.
Limitations: expensive, larger, higher power consumption, and the gearbox oil needs attention.
Full comparison
| Feature | Solenoid | Motorised (MAX) |
|---|---|---|
| Capacity | 6 – 10 LPH | 25 – 400 LPH |
| Pressure | 4 kg/cm² (10–15 on HP) | 5 kg/cm² |
| Starting price | ₹5,460 | ₹25,725 |
| Power supply | Single phase 230V | Single or 3 phase 415V |
| Power consumption | Very low | 0.25 – 0.5 HP |
| Continuous running | Acceptable, coil warms | Suitable for 24 hours |
| Maintenance | Diaphragm, valves | Diaphragm, valves, gearbox oil |
| Space required | Very little | More, plus a base |
| Noise | A light ticking | Motor noise |
Solenoid models
| Model | Capacity | Price |
|---|---|---|
| Edose 6 LPH | 6 LPH @ 4kg | ₹5,460 |
| NEO 6 LPH | 6 LPH @ 4kg | ₹6,090 |
| NEO 10 LPH | 10 LPH @ 4kg | ₹7,035 |
| NEO PRO 10 LPH | 10 LPH plus switch | ₹15,750 |
| Edose HP | 10 LPH @ 10kg | ₹28,875 |
Motorised (MAX) models
| Model | Capacity | Power | Price |
|---|---|---|---|
| MAX 25 | 25 LPH | Single phase | ₹25,725 |
| MAX 40 | 40 LPH | Single phase | ₹28,350 |
| MAX 50 | 50 LPH | 0.25HP, 3 phase | ₹38,325 |
| MAX 100 | 100 LPH | 0.25HP, 3 phase | ₹38,325 |
| MAX 200 | 200 LPH | 0.25HP, 3 phase | ₹41,475 |
| MAX 300 | 300 LPH | 0.5HP, 3 phase | ₹51,450 |
| MAX 400 | 400 LPH | 0.5HP, 3 phase | ₹51,450 |
Real examples
| Setup | Dosing needed | Choice |
|---|---|---|
| 500 LPH RO, antiscalant | ~50 ml/hr | Solenoid 6 LPH |
| 5,000 LPH RO, antiscalant | ~500 ml/hr | Solenoid 10 LPH |
| 20 KLD STP, chlorine | ~2 LPH | Solenoid 10 LPH |
| 100 KLD ETP, polymer | ~30 LPH | Motorised MAX 40 |
| Large ETP, lime dosing | ~150 LPH | Motorised MAX 200 |
Notice that however large an RO plant becomes, the dosing stays within solenoid range. Motorised pumps are really for ETP and STP, where chemical volumes are far higher.
PTFE versions in the motorised range
For aggressive chemicals the MAX series is available in PTFE:
- MAX 25 PTFE — ₹42,000
- MAX 40 PTFE — ₹44,625
- MAX 50/100 PTFE — ₹56,700
- MAX 300/400 PTFE — ₹71,400
The full material chart is in our PVDF vs PP guide.
The decision in 30 seconds
- Work out your dosing in LPH (see the calculation guide)
- Up to 10 LPH → solenoid, decision made
- Above 25 LPH → motorised MAX
- In between (10 to 25) → a more concentrated solution may keep you within solenoid range; ask us
Solenoid or motorised — we will advise
Tell us your dosing in LPH, the chemical and the plant type, and we will recommend the right pump.
💬 WhatsApp par poochhein 📞 9910646957Frequently asked questions
What is the difference between solenoid and motorised dosing pumps?
In a solenoid pump an electromagnet drives the diaphragm; these are compact, economical and go up to about ten LPH. A motorised pump uses a motor and gearbox, starts at around twenty five LPH and is built for heavy continuous duty.
Does an RO plant need a motorised pump?
Usually not. However large the plant, RO antiscalant dosing stays within solenoid range. Motorised pumps are really intended for ETP and STP work where much larger chemical volumes are required.
Do motorised pumps need more maintenance?
Slightly. Diaphragm and valves need attention on both types, but a motorised pump also has gearbox oil to check periodically. In return it is far more robust for continuous running.
Can a solenoid pump run continuously for 24 hours?
It can, but the coil warms up, so very prolonged heavy duty will shorten its life. For genuinely continuous heavy dosing a motorised pump is the better choice.
Why do MAX 50 and MAX 100 cost the same?
The basic build and motor are the same, with only the dosing head setting differing. So if there is any chance the requirement will grow, taking the larger model makes sense because it costs nothing extra.