DI Series – Displacement Transducer

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Product ManualProduct DatasheetDI 5XX / DI 6XX DrawingDI 63X Drawing

Product Description

Magtrol’s line of Displacement Transducers provide contactless measurement of absolute piston position in hydraulic and pneumatic cylinders and other applications. Their robust construction, large insensitivity to shocks and very long life (due to no moving parts and therefore no wear of components) make them both cost effective and very reliable. Magtrol transducers offer a wide range of operational temperatures and admissible pressure resistance for even the most demanding applications.

The transducer provides a direct 4-20 mA output signal corresponding to the measuring range, as well as VDC temperature output.

Features

  • Large measuring range: Piston displacements from 50 to 1000 mm (80 to 250 mm for DI 63X models)
  • Current-based output signal (4 to 20 mA) for displacement
  • Built-in temperature measurement (VDC output)
  • Very long life: No moving parts and therefore no wear of components (Eddy-current principle)
  • Insensitive to metallic impurities in the working fluid
  • High shock and vibration resistance
  • Capable of withstanding pressures up to 450 bar
  • Robust construction, designed for permanent operation in hydraulic systems
  • Standard temperature version, up to 80 °C (DI 5XX)
  • High temperature versions, up to 125 °C (DI 60X and DI 61X) or up to 200 °C (DI 63X)
  • EMC susceptibility conforms to European standards

Specifications

MODELDI 5XX
STANDARD TEMPERATURE		DI 6XX
HIGH TEMPERATURE		DI 63X
HIGH TEMPERATURE
MEASURING RANGES a)
Rated Values b)50, 100, 160, 250, 300,
400, 630, 1 000 mm		50, 100, 160 mm80, 130, 200, 250 mm
Zero PositionDefined by inserting the transducer probe into the measurement tube as far as Xmin a)
Full-scale PositionDefined by inserting the transducer probe into the measurement tube as far as Xmax a)
DISPLACEMENT MEASUREMENT
Linearity Error0.5 %, typically < 1 % d)
Resolution< 0.05 % d)
Repeatability< 0.05 % d)
White noise on output current< 0.2 μAeff / √Hz (DC to 1 kHz)
OUTPUT SIGNAL c)
Displacement OutputCurrent source with imposed 4 to 20 mA signal.
The output current is independent of the load resistance, provided it remains within limits.
ZeroAdjusted to 4 mA (± 0.08 mA)Adjusted to 20 mA (± 0.08 mA)
Full ScaleAdjusted to 20 mA (± 0.15 mA)Adjusted to 4 mA (± 0.15 mA)
Admissible Load0 to 500 Ω
Frequency Response0 to 1 000 Hz (-1 dB)
with 4th-order Butterworth-type response		0 to 820 Hz (-1 dB) with 4th-order
Butterworth-type response
TEMPERATURE OUTPUT
Offset Voltage7.5 VDC ±80 mV at 20 °C7.5 VDC ±60 mV at 20 °C
Temperature Signal30 mV/°C, accuracy ±5% typically
(±10% max.)		10 mV / °C, accuracy ±10 %
typically (± 20 % max.)		10 mV/°C, accuracy ±10%
typically (±15% max.)
Output Resistance1 kΩ
ELECTRICAL CHARACTERISTICS & CONNECTIONS
Supply Voltage20 to 32 VDC
Consumption≤ 70 mA
Supply Voltage Influence (Displacement)< 10 ppm of FSD for 1 V variation (DC to 100 Hz)
Supply Voltage Influence (Temperature)< 0.1°C over the range 20 to 32 VDC
ConnectionWatertight 5-pole bayonet connector; Watertight mating plug
(straight or elbowed)		7 silicon wires: 0.09 mm²
length: 0.6 m
Protection Against Polartiy InversionNo danger to the transducer in event of incorrect connection
ENVIRONMENT & MECHANICAL CHARACTERISTICS
Operating Temperature- 40 °C to + 80 °C- 40 °C to + 125 °CMeasuring Rod: - 40 °C to + 200 °C
Electronics: - 40 °C to + 125 °C
Storage Temperature- 45 °C to + 130 °C
Temperature Influence (Zero)< 150 ppm/°C d)
Temperature Influence (Sensitivity)< 150 ppm/°C d)
Temperature Influence on Drift
(zero + sensitivity)		1.5% of FSD over the entire operating temperature range
Maximum Admissible Pressure450 bar
Admissible ShockHalf-sine, duration 3 ms, radial 100 g, axial 300 g
Protection ClassIP 66, according to DIN 40050
EMC / EMI compatibilityAccording to IEC 61326-1 / IEC 61321-2-3

a) Refer to dimension section
b) According to “Linear Measuring Range” dimension (see dimension section)
c) Calibrated standard signal. Transducer and measuring tube are calibrated in the factory for standard measuring ranges mentioned at the top of this table in section «Measuring Ranges»
d) of FSD (Full Scale Deflection)

Operating Principles

Eddy-Current Principle

Magtrol Displacement Transducers use the principle of Eddy-current measurement. An aluminum tube moves along the transducer’s coil changing the induced Eddy-current losses, thus changing the coil impedance. An electronic circuitry housed in the transducer head, transforms the information of the measuring tube position into a linear signal. This circuitry uses modern SMD (surface-mounted device) technology, giving it robustness and reliability. The sensor is actively compensated for temperature changes.

Characteristics of the Output Signal

DI Series Displacement Transducers have a basic 3-wire configuration, providing a 4–20 mA current (20–4 mA for DI 63X models) proportional to the position of the aluminum tube. An indication of the temperature within the probe is also provided as a voltage output.

In closed-loop systems, a specific piston position can be repeatedly achieved with a precision better than 0.05‰ full scale (i.e. better than 50 µm for a measuring range of 1 m).

Applications

The DI series of displacement transducers were developed principally for OEM applications in the hydraulic industry. They enable the direct and reliable measurement of the position of:

  • Hydraulic Cylinder
  • Steam Inlet Valves
  • Propellers
  • Stone Crusher
  • Servo Controls
  • Control Valves

Their design is such that the installation cost is kept to a minimum. This cost-effectiveness results from the limitation to one fixed standard signal of 4 to 20 mA with very precise determination of the measurement interval (from 0 to full scale) on the sensing element.