DE51 Electronic position indicators absolute reading, direct drive, technopolymer

  • RoHS
  • IP65
  • PA
  • g50


Main specifications

Base and case

Polyamide based (PA) technopolymer certified self-extinguishing UL94 V-0.
Black base.
Black case, glossy finish.


  • Backlit LCD display showing two values: target position and current position.
  • Adjustable reading (upper and lower).
  • Cursor to indicate the rotation direction (clockwise/anti-clockwise) to reach the target position.
  • Values displayed in mm or inches.
The visualization parameters can be set and modified by software at the installation of the machine.

Front membrane

Polyester. Resistant to solvents, alcohol, acids, alkali.

Internal gasket

O-ring front sealing in NBR synthetic rubber, between the case and the bushing.

Rear gasket

Polyurethane, supplied.


Black-oxide steel with Ø 14 mm H7 reamed hole, fitting to shaft by means of a supplied grub screw with hexagon socket and cup end UNI 5929-85.

Standard executions

  • DE51-F: front display, output with connectors.
  • DE51-F-Cable: front display, output with cable and connectors.
  • DE51-A: inclined display, output with connectors.
  • DE51-A-Cable: inclined display, output with cable and connectors.

IP protection

Completely sealed indicator with IP 65 protection class, see EN 60529 table.

General information

Features and applications

DE51 indicators can be used on passing through spindles in any position to give absolute reading of the current position and of the target one of a machine component.
DE51 indicator is a sophisticated measuring system based on an absolute multi-turn encoder and it is not affected by magnetic fields. Therefore it is able to guarantee perfect operation, even in the presence of electric motors.
Thanks to the long-life lithium battery (more than 10 years of life-expectancy) spindle positioning variations can be registered even when the power supply is off and it prevents the loss of the preset values in case of an electrical power failure.
DE51 indicators must be networked to the central memory unit (call Elesa Customer Care) or directly to the PLC.
The connection of DE51 electronic indicators directly to the PLC of the machine functions also as a safety system. In fact, in case of mismatch for the target position of even one DE51, the PLC prevents the machine from starting working, thereby avoiding inaccurate work.
Mechanical and electrical characteristics
Input24 Vdc ± 20%, 30mA
Buffer memory3V lithium battery
min. guaranteed life expectancy 10 years for recording current and target values
ConnectionM8 - 4PIN
MAX RPM number600 RPM
Weight120 g
Working temperature0 ÷ 50 °C
Storing temperature-20 ÷ +70 °C
Relative humidity80% at 25°C without condensation
Protection classIP 65 according to IEC 529
General classification according to EN 61010 part 1Protection class II
Overvoltage protection category II
Contamination factor 2
Immunity to interferenceAccording to EN 61000-6-2
Interference emissionAccording to EN 61000-6-3


Accessories on request (to be ordered separately)

  • Connection cables between PLC or central memory unit and DE51 or between two DE51 with different lenghts (see table)
  • Terminal resistor to avoid noises and interferences on the net (see table)
CE.99136CABLE-M8-SC-5mtConnection cable between central memory to DE51
CE.99141CABLE-M8-1mtConnection cable for DE51
(length 1m)
CE.99143CABLE-M8-3mtConnection cable for DE51
(length 3m)
CE.99145CABLE-M8-5mtConnection cable for DE51
(length 5m)
CE.99146CABLE-M8-6mtConnection cable for DE51
(length 6m)
CE.99156RE-M8-120ohmResistore terminale
(resistance value 120ohm)
  • RB51: black-oxide steel reduction sleeves (see table).
  • MD51: polyamide based (PA) technopolymer fluted grip control knob.

Assembly instructions

Assembly instructions

  1. Drill a Ø 6 mm by 10 mm hole in the body of the machine with a 22 mm centre distance from the spindle to fit the rear referring pin.
  2. Set the spindle to the start or referring position.
  3. Fit the indicator onto the spindle and make sure that the referring pin fit the hole.
  4. Clamp the bushing to the spindle by tightening the grub screw with hexagon socket and cup end UNI 5929-85.
  5. Network the indicator using cables with connectors type M8-4PIN (see table "Mechanical and electrical characteristics").
Electronic position indicators absolute reading, direct drive, technopolymer DE51
Code Description Weight
CE.99111 DE51-F-F.14 125
CE.99121 DE51-A-F.14 125
CE.99112 DE51-F-F.14-Cable 125
CE.99122 DE51-A-F.14-Cable 125