Level switches for silos and grain
Answer two questions and we will point you to the right level switch for your silo, vessel or conveyor.
Find the right level switch
Level Switch NV14P
Flush mounted in the silo wall with a flange and rubber gasket, accessible from inside the vessel. An air inlet with a sintered bronze filter compensates for pressure changes inside the housing.
View NV14PThink about where you place it. High up in the silo the switch works as a full-level alarm that stops filling. Low down it works as dry-run protection that stops the discharge screw before it runs empty. Many plants use one of each.
Level Switch NV14P-KM
The same function as the NV14P, but the air inlet is replaced by a compensation diaphragm. That is required when the switch sits inside the vessel, and it also gives IP65 for damp and heavily dusty conditions.
View NV14P-KMThink about where you place it. High up in the silo the switch works as a full-level alarm that stops filling. Low down it works as dry-run protection that stops the discharge screw before it runs empty. Many plants use one of each.
Level Switch NV10P
Overflow protection for screw conveyors, belt conveyors and elevators. The small-diameter diaphragm needs a distinct force, so the switch triggers only once material has genuinely built up against it — not as material passes normally.
View NV10PWire it to stop the feed before the conveyor jams when there is a blockage downstream.
Level Switch NV10P-KM
The same overflow protection as the NV10P, but with a compensation diaphragm so the switch can be mounted inside the conveyor. IP65 for damp and heavily dusty conditions.
View NV10P-KMWire it to stop the feed before the conveyor jams when there is a blockage downstream.
- Fully mechanicalNo electronics, no calibration
- Volt-free signal125 VAC / 15 A · 24 VDC / 0.5 A
- Stock in StockholmDespatch 1–2 working days
- 24-month warrantyQuotation on request
Prices are shown in your local currency on each product page.
None of the options fit?
Describe the plant — the material, where the switch will sit and what it has to control — and we will come back with a concrete suggestion. Normally within 1–2 working days.
info@levelswitchsweden.com · +46 8 32 33 00
More about the switches
Specification
| Housing | Oven-lacquered die-cast light alloy |
|---|---|
| Diaphragm | Oil-resistant nitrile rubber |
| Operating temperature | +1 °C to +60 °C |
| Microswitch | 125 VAC / 15 A · 24 VDC / 0.5 A |
| Cable entry | 18.6 mm threaded connection, PG11 cable gland |
| Enclosure rating | IP54 (NV14P, NV10P) · IP65 (KM versions) |
| Diaphragm travel | Approximately 3–4 mm |
| Weight incl. packaging | 0.8 kg |
Why a mechanical switch in grain and dry bulk
A grain silo is a difficult environment for measurement. Dust settles on everything, moisture content varies with the harvest and the weather, and material builds up on the walls. Capacitive and optical sensors are affected by exactly this and need recalibrating when the material changes character.
The diaphragm switch senses physical pressure from the material against a rubber diaphragm, which actuates a microswitch. There is no electronics to disturb, no setting that drifts, and nothing to recalibrate when you go from oats to wheat. Diaphragm travel is limited to approximately 3–4 mm, so the internal parts are not damaged by high material pressure.
The diaphragm is the only wearing part and can be replaced separately.
Materials and typical plants
Grain, seed, animal feed, pellets, wood chips, granulates, plastic pellets, beans, powders, sand, gravel and coal. The NV14 series is intended for heavier granular material; the NV10 is used as overflow protection for lighter material as well.
Grain silos on farms · feed mills and flour mills · pellet and wood chip plants · cleaning machines, dryers and weighing equipment · sand and gravel depots.
Frequently asked questions
Which level switch should I choose for a grain silo?
The NV14P if the switch is mounted in the silo wall and accessible from outside. The NV14P-KM if it has to sit inside the silo, or if the environment is damp and dusty — that calls for a compensation diaphragm and IP65.
Does the switch work in a dusty environment?
Yes. The switch senses physical pressure from the material, not an electrical or optical property. Dust and build-up therefore do not affect how it works. In particularly dusty or damp positions, choose the KM version with IP65.
Does it need recalibrating if I change material?
No. There is no setting to adjust when moving between, say, oats, wheat and feed. Note, however, that the NV14 series is intended for heavier granular material — for very light materials, contact us first.
Can the switch be used in a pressure vessel?
No. Positive pressure in the vessel cannot be compensated, so diaphragm switches must not be used in pressure vessels.
How quickly can you deliver?
We hold stock in Årsta, Stockholm and normally despatch within 1–2 working days. Shipping is calculated at checkout by consignment size.