Hydac HNT 1226-B-0280-000 Level Transmitter, 0 to 10 V

A float level transmitter with a 0 to 10 V output

The Hydac HNT 1226-B-0280-000 (HYDAC part number 924387) is a float-based level transmitter from the HNT 1100 family. A magnetostrictive sensor follows the float position and outputs a continuous 0 to 10 V signal proportional to the fluid level, so a PLC analogue input can display the tank content directly. The pressure-resistant stainless steel housing screws into the tank wall through a G3/4 A thread.

The probe in this code is 280 mm (11.02 inches) long with a measuring range of 0 to 208 mm, and the output is available as 0 to 10 V on three conductors through a four-pole M12x1 connector.

Technical specifications

Code decoding

HNT 1 2 2 X – X – XXXX – 000 in the datasheet: 2 means no temperature sensor, 2 the G3/4 A thread, then the electrical connection (1 flying lead 2 m, 6 four-pole M12x1, 8 five-pole M12x1), then the output (B is 0 to 10 V, C is 4 to 20 mA on three conductors), and the probe length in mm. For HNT 1226-B-0280-000 that gives a 280 mm probe, 0 to 10 V and the four-pole plug. Pin 1 is +UB, pin 3 is 0 V and pin 4 the signal.

Choosing output and probe

If the controller expects a current loop, order the C version; for long cable runs a 4 to 20 mA output generally resists interference better than a voltage signal. The datasheet lists probe lengths of 250, 280, 370, 410, 520 and 730 mm as standard, with up to 2500 mm on request. A switch version of this family, the HNS 3000, is also in our catalogue and adds a display and relays. The USA datasheet for this transmitter is E 18.604.1.0.

Fit the float over the rod in the correct orientation before closing the tank, keep the probe away from suction flows that could tilt the float, and check the clearance below the lowest level required. Allow for the dead zones at the top and bottom of the rod, where the sensor cannot follow the float, when you convert the signal to tank volume in the PLC, and scale the 0 to 10 V span to the 208 mm measuring range.

Documents and quotation

The datasheet is attached. Send the tank depth, the fluid and the required output. See also our level instrumentation range.

How the HNT 1226-B-0280-000 works

The HNT 1226-B-0280-000 works on the magnetostrictive principle. A waveguide inside the stainless steel probe tube carries a short current pulse from the sensor head. The float, which carries a ring magnet, rides on the tube at the liquid surface. Where the pulse’s magnetic field meets the field of the float magnet, a mechanical torsion wave is created in the waveguide and travels back to the head. The time between the start pulse and the returning wave is measured and converted into the float position. The electronics then scale this position over the measuring range and output it as a 0 to 10 V signal on the 3-conductor connection.

Because the position is measured without contact, there is no wiper or reed chain to wear, and the signal changes continuously rather than in steps. HYDAC specifies a rise time of 30 ms and accuracy, non-linearity, repeatability and hysteresis of ±1 % FS each to DIN 16086, for calm, non-turbulent fluid.

Signal scaling and wiring

The output signals can be connected to HYDAC measurement and control devices and to standard evaluation systems such as PLC analogue inputs. Reverse-polarity protection of the supply, excess-voltage, override and short-circuit protection are provided.

HNT 1226-B-0280-000 selection & ordering guide

• Electrical connection: 1 = flying lead 2 m (core colours brown +UB, white 0 V, green signal); 6 = M12×1 4-pole (this model); 8 = M12×1 5-pole.
• Output: B = 0 to 10 V (this model); C = 4 to 20 mA, load max. 500 Ω.
• Probe length: 0250, 0280, 0370, 0410, 0520 or 0730 mm, with matching measuring ranges of 7.01, 8.19, 11.73, 13.31, 17.64 and 25.90 in. Other lengths are available on request.
• Floats: several float variants exist, including stainless steel for aggressive media and polypropylene (0.6 kg/dm³). Check the float density against your fluid.

Our team can help confirm the correct ordering code when you replace an existing transmitter or need a different probe length.

Installation & maintenance

• The pressure-resistant stainless steel housing screws into a G3/4 A port. Maximum tank pressure is 43.5 psi, or 145 psi for less than one minute.
• Use a shielded cable for the analogue signal and keep it apart from motor and solenoid power wiring; for long runs the 4 to 20 mA version is the better choice.
• Check that the float slides freely and that sludge has not built up on the tube during scheduled tank service.
• Verify the signal at the lowest and highest levels after installation and set the PLC scaling to match.

Typical applications in Oman & the GCC

Continuous level signals are used for tank content display, refill control and early warning of leaks in hydraulic power units, lubrication systems and cooling-lubricant tanks on machine tools. In Oman and the GCC the HNT 1000 suits industrial hydraulics in steel, aluminium and cement plants, port cranes, and power units on oil and gas skids where a PLC tracks the tank level and trends oil loss over time.

Why source from Seven Star LLC

Seven Star LLC supplies HYDAC level transmitters and matching M12 connectors across Oman and the GCC. Request a quote for the HNT 1226-B-0280-000 and include the tank depth, fluid and required output.