How to Choose a Level Switch: A Practical Trumen Guide
Five questions that point you to the right technology before you spend money on the wrong one.
Most level-switch failures are not faulty products — they are the wrong technology for the material. A float that sticks in syrup, a paddle that wears out in cement, a conductivity probe in diesel. This guide compares the main Trumen level switch technologies and shows which one fits your tank, silo or pipe.
Level Switch Technologies Compared
| Technology | Works on | Strengths | Watch out for |
|---|---|---|---|
| Vibrating fork (LFV, LSV) | Liquids and powders | No calibration, no moving parts, ignores foam | Heavy drying build-up between tines; lumps over 10 mm |
| Capacitance / RF (LMC) | Liquids, slurries, powders | Long probes, handles coating, rope up to 20 m | Needs a sensitivity setting; low-dielectric materials |
| Conductivity | Conductive liquids only | Low cost, several levels on one probe | Oils, fuels and powders cannot be sensed |
| Float | Clean liquids | Simple and visible | Sticks in viscous or dirty liquids; moving parts |
| Rotary paddle | Powders and granules | Easy to understand | Motor and bearing wear; slow response |
Five Questions Before You Order
- What is the material? Liquid, powder, granule or slurry — and is it conductive, sticky, foamy or abrasive?
- How dense is it? For powders, bulk density decides the fork size: 50 g/l needs a D1 fork, 300 g/l works with a D3.
- Where will it mount? Side, top or in a pipe? Insertion length and process connection (BSP, NPT, Tri-Clamp or flange) follow from this.
- What are the process conditions? Temperature, pressure and whether the area is hazardous (flameproof housing needed).
- What must it switch? A PLC input (PNP), a contactor (relay), or a 2-wire loop — and should it fail safe high or low?
Our Quick Recommendations
Clean or viscous liquids
Use a Trumen LFV12 in pipes and small tanks, or an LFV11 where the nozzle is deeper. Read the LFV guide →
Powders and granules
Use a Trumen LSV with the fork sized to bulk density. Read the LSV guide →
Sticky, coating or tall vessels
Use a Trumen LMC capacitance switch with rod or rope probe. Read the LMC guide →
High Alarm or Low Alarm — Set the Fail-Safe Right
Maximum fail-safe (high level)
The output is energised while the sensor is free and drops out when covered — or when power or a cable fails. Use it for overfill protection.
Minimum fail-safe (low level)
The output is energised while the sensor is covered and drops out when uncovered or on failure. Use it for pump dry-run protection.
One of Each Technology in Stock
Level Switch Selection FAQs
Which level switch works for both liquids and powders?
Both the vibrating fork (LFV11 or LSV) and the capacitance LMC can handle liquids and solids. The fork needs no calibration; the LMC handles sticky products and long probes better.
What is the most maintenance-free option?
A vibrating fork. It has no moving parts and no set-up, so it usually runs for years with only occasional cleaning.
Can I use a conductivity switch for diesel?
No. Diesel and oils do not conduct. Use a vibrating fork or capacitance switch instead.
What does fail-safe mean on a level switch?
It decides which state the output goes to if power or wiring fails, so the plant always falls to the safe condition.
Which switch for a cement silo?
A Trumen LSV with a D2 fork for high-level alarms is the common choice; a rope-probe LMC can serve low-level alarms in tall silos.
Do you help with selection?
Yes. Send the material, vessel details and output needed, and our engineers will recommend a model and quote from stock.
Not Sure Which Level Switch?
Send us the material, vessel type and size, temperature, pressure and the signal you need. We will recommend the right Trumen switch and quote.
Office Address
F412 (4th floor), Plot No-21, Arthamart, Techzone-4, Noida Extension, UP — 201318
By appointment only
📋 Quick Enquiry
Reply within business hours on WhatsApp and email.
⚡ Prefer Quick Phone Consultation?
Call our application engineers directly for immediate assistance and personalised recommendations. Office Time: 10:00 AM – 6:00 PM (Mon–Sat).
📞 Call Sales: +91 99530 39482 📞 Support: +91 99530 39482