Product Information

ECN 425
EQN 437
Absolute Rotary Encoders
with EnDat22 for SafetyRelated Applications
ID 1327454-xx
ID 1327455-xx

06/2022

ECN 425, EQN 437
Rotary encoders for absolute position values with safe singleturn information• Blind hollow shaft with steel clamping ring:¬ 12 mm (68S)¬ 10 mm (68T)

Required mating dimensions

Specifications

ECN 425

EQN 437

Functional safety
for applications with up toAs a single-encoder system for monitoring functions and control-loop functions:• SIL 2 as per EN 61508 (further basis for testing: IEC 61800-5-3)• Category 3, PL d, according to EN ISO 13849-1:2015
Safe in the singleturn rangePFH1)

 10 · 10–9 (probability of dangerous failure per hour)

Safe position2)

Encoder: ±1.76° (safety-related measuring step: SM = 0.7°)
Mechanical coupling: ±2° (fault exclusion for the loosening of the shaft and stator coupling;
designed for accelerations  300 m/s2; flange socket design:  150 m/s2)

Interface/ordering designation

EnDat 2.2/EnDat22

Position values per revolution

33 554 432 (25 bits)

Revolutions–Calculation time tcal/clock frequency 7 µs/ 16 MHz

System accuracy at 20 °C±20”Supply voltage

DC 3.6 V to 14 VPower consumption3) (maximum)

At 3.6 V:
At 14 V:

Current consumption (typical)

At 5 V: 80 mA (without load)

Electrical connection*

8-pin M12 radial flange socket or PUR cable (1 m) with 8-pin M12 coupling (male)

Cable length4)

 100 m (at clock frequency ≤ 8 MHz) 20 m (at clock frequency ≤ 16 MHz)

Shaft*

Blind hollow shaft D = 12 mm or D = 10 mm

Permissible shaft speed 6000 rpm

Starting torque at 20 °C

 0.01 NmMoment of inertia of rotor 6 · 10–6 kgm2

Angular acceleration of rotor 4 · 104 rad/s2

4096 (12 bits)

 600 mW
 700 mW

At 3.6 V:
At 14 V:

 700 mW
 800 mW

At 5 V: 95 mA (without load)

Permiss. axial motion of measured shaft  ±1 mm

A = Bearing of mating shaft
M1 = Measuring point for operating temperature
M2 = Measuring point for vibration
1 = Connector coding
2 = X8 clamping screw with hexalobular socket; tightening torque: 1 Nm ±0.06 Nm
3 = Compensation of mounting tolerances and thermal expansion; no dynamic motion permitted
4 = Protection against contact as per EN 60529
5 = Chamfer at start of thread is obligatory for material bonding anti-rotation lock
6 = Direction of shaft rotation for ascending position values

2

Product Information ECN 425/EQN 437   06/2022

Vibration 55 Hz to 2000 Hz5)
Shock 6 ms

22
 300 m/s ; flange socket version: 150 m/s (EN 60068-2-6)
2
 2000 m/s (EN 60068-2-27)

Operating temperature6)–30 °C to 100 °C

Trigger threshold for exceeded
temperature error mesage7)

125 °C in the scanning ASIC (measuring accuracy of the internal temperature sensor: ±1 K)

Relative humidity

 93% (40 °C/21 d as per EN 60068-2-78), condensation excluded

Protection rating EN 60529

IP67 on housing; IP64 at shaft inlet(read about insulation under Electrical safety in the Interfaces of HEIDENHAIN Encoders
brochure; contamination from the ingress of fluids must be avoided)Mass 0.3 kg

ID number

1327454-03/1327454-05/1327454-06/
1327454-04 (rapid delivery as preferred version)* Please select when ordering1)	For use at ≤ 2000 m above sea level(≤ 6000 m above sea level upon request)2)	Further tolerances may arise in the downstream electronics
after position value comparison (contact manufacturer)3)	See General electrical information in the Interfaces ofHEIDENHAIN Encoders brochure
Product Information ECN 425/EQN 437   06/2022

1327455-03/1327455-05/1327455-06/
1327455-04 (rapid delivery as preferred version)4)	See the EnDat description in the Interfaces of HEIDENHAIN Encoders
brochure5)	10 Hz to 55 Hz constant over 4.9 mm peak to peak(flange socket design: 2.45 mm peak to peak)6)	For information on operating temperature, shaft speed, and supply
voltage, see General mechanical information in the Rotary Encoders
brochure7)	The internal temperature evaluation is not designed with functionalsafety3

MountingElectrical connection

Mounting
The rotary encoder’s hollow shaft ispressed onto the measured shaft andclamped on its rotor side via a screw(tightening torque: 1 Nm ±0.06 Nm). The
stator is connected without a centeringcollar on a flat surface.

Pin layout

With standard stator coupling
Blind hollow shaft

8-pin M12 flange socket or 8-pin M12 couplingPower supplyFor the hollow-shaft connections 68S and68T, repeated fastening reduces the screw
retaining force. In order to maintain therequired safety factor for friction-locked
connections, the maximum permissible
number of fastening procedures is limited
to four. Beyond this number of repetitions,mechanical fault exclusion cannot beguaranteed. In such cases, new clamping
rings must be separately ordered:
Clamping ring for 10 mm
Clamping ring for 12 mm

8251

3476UP

Sensor UP0V

Sensor 0 VDATADATA

CLOCKCLOCKBrown/GreenBlueWhite/GreenWhiteGrayPinkVioletYellow

Cable shield connected to housing; UP = Power supply voltage
Sensor: The sense line is connected in the encoder with the corresponding power supply line.
Vacant pins or wires must not be used!
Note for safety-related applications: Only completely assembled HEIDENHAIN cables are qualified. Do not modify cables or exchange
their connectors without first consulting with HEIDENHAIN Traunreut!

ID 540741-06
ID 540741-07

Cables with a length of more than 0.5 m
must be provided with strain relief.

Serial data transmission

More information:
For the customer-side mounting design,
the material specifications for steel apply
to the customer-side shaft, and for thecustomer-side stator, the material
specifications for aluminum apply.
Note the other material properties in theRotary Encoders brochure.
For mounting tips and mounting aids,
see the Mounting Instructions and theRotary Encoders brochure.

DR. JOHANNES HEIDENHAIN GmbH
Dr.-Johannes-Heidenhain-Str. 583301 Traunreut, Germany +49 8669 31-0
 +49 8669 32-5061
info@heidenhain.dewww.heidenhain.com

4

Product Information ECN 425/EQN 437   06/2022

1378398 · 00 · A · 02 · 06/2022 · PDF

This Product Information document supersedes all previous editions, which thereby
become invalid. The basis for ordering from HEIDENHAIN is always the Product
Information document edition valid when the order is placed.

More information:
Comply with the requirements described in the following documents to ensure correctand intended operation:• Operating Instructions				
1379273-xx