Product Information

MRP 8081 Dplus
Angle Encoder Modulewith Four Scanning Headsand Compensation Data

07/2023MRP 8081 Dplus

Mating dimensions of the mounting parts

Angle encoder module with four scanning heads and compensation data
• Very high system accuracy• Resilient angle measurement• Hollow shaft  100 mm• Axial load of up to 300 N
37.6  0.5

33.5



32.6  0.5

A

2  0.2

B-B

A-A
0.01 B
0.004 B

0.004 B≥  113
 104.5≤  96≥ 10

 112 f79

 0.025 A5
 0.025 A

6

 0.025 A

 160 f710

 100 H7 


0.01 B5

 100 H7 

640.01 B

6x1.5°

60

100 f7  0.2 ARz 16Rz 10







≤  134 ≥  164≥ 13

A
M4 (6x) t=4.6

A0.003
 3.4 (12 x 30°)

6x 60°
30°(122 A
 0.

0.005


8

 14

Rz 16
Rz 100.003

 100 f7  ≥  116 ≤  96≥ 13M3



1.5



1.2 ... 3 6.4x) t=

 160 H7  174 ± 0.5

12x 30°M104.54(6 x) t
0. =63.
A 42

Note the information on mechanical design types and mounting.
K = Required mating dimensions
1 = Tightening torque of the M3 – 8.8 cylinder head screws: 1.1 Nm ±0.05 Nm
2 = Tightening torque of the M4 – 8.8 cylinder head screws: 2.5 Nm ±0.13 Nm
3 = Mark for 0° position ±5°
4 = Direction of shaft rotation for output signals as per the interface description
5 = Required mounting dimensions for the transfer of the maximum permissible loads as per the specifications
6 = Optional: recommended mating dimensions
7 =	Material for customer‘s mounted parts: SteelRe ≥ 235 N/mm2		Rm ≥ 400 N/mm2
8 = Thermal expansion coefficient therm: 10 · 10–6 K–1 to 16 · 10–6 K–1
9 = Recommended direction of force; the recommended direction of force is to be maintained if dynamic overloading is possible

Preliminary Product Information for the MRP 8081 Dplus  07/2023

Preliminary Product Information for the MRP 8081 Dplus  07/2023

3

Transferable accuracy

Specifications

In order to achieve accuracies in the high-end range, customers must often perform avery complex and time-consuming calibration of the entire machine. Under the motto“transferable accuracy,” HEIDENHAIN contributes to facilitating the mounting process
for the customer and to transferring the high accuracy of our encoders to the customer’s
application without any losses. For the MRP 8081 Dplus encoders, this is achieved basedon the following features:

Encoder

Incremental
MRP 8081 Dplus

Measuring standard

OPTODUR circular scale

Signal periods

63 000

System accuracy±0.40”

Position error per signal period±0.06”

Repeatability

From both directions: 0.1”

RMS position noise

Typically 0.0015”• Sturdy, mechanical interface for mounting on the customer side
• Combination of rigid bearing unit and already adjusted scanning• Four scanning heads for position calculation for resilient angle measurement• Compensation data for boosting the system accuracy
Electrical connection
The MRP 8081 Dplus angle encoder
module provides four separate connections(D-sub, 15-pin) with 1 VPP interface. The
EIB 74x signal converters that are available
from HEIDENHAIN can be used to operate
the product. The product can also beconnected to downstream electronics fromthird-party suppliers if they provide four
1 VPP inputs.
Compensation data file
The included compensation data file in CSV
format basically contains a two-dimensionaltable. In this table, the angular positions
from the four scanning heads, which havealready been taken into account in thecalculation, are assigned the corresponding
compensation values for boosting theaccuracy. The compensation data file isprovided on a USB stick together with theencoder.

Xavg in °Xavg =1)

(X1abs + X2abs + X3abs + X4abs)4X1abs ... X4abs:	Positions of the scanningheadsXavg:		Arithmetic mean value ofinputs X1abs to X4abs

Interface

4 x  1 VPPReference marks

150 (distance-coded)

Cutoff frequency –3 dB≥ 500 kHz1)

Electrical connection

4 x 1.5 m cable with 15-pin D-sub connector; interface electronics inside the connector1)≤ 30 m (with HEIDENHAIN cable)

Cable length1)

DC 5 V ±0.25 V

Supply voltage

Mounting option 11)

For more information about implementing
the position calculation, please refer to theMRP 8081 Dplusinstallation instructions.



5.25 V: ≤ 950 mW

Power consumption(maximum)

1)

Current consumption (typical)

1)

175 mA (without load)

Separate electrical connection for each scanning headCorr in ”

0.489
0.397
0.274
0.188
0.144
0.151





Mounting option 2

1 Customer rotor (mounting option 1)
2 Customer stator
3 Customer rotor (mounting option 2)
4 Scanning head 1 (with ID label)
5 Scanning heads 2 to 4 (without ID label)
6 ID label

Corr in ”

05.625
11.25016.87522.50028.125

Position calculation with an EIB 74xor downstream electronics fromthird-party suppliers
For the system to be able to reach thespecified accuracy, the positions of all
scanning heads need to be averaged.

MRP 8081 Dplus
Xavg in °4Preliminary Product Information for the MRP 8081 Dplus  07/2023

Preliminary Product Information for the MRP 8081 Dplus  07/2023

5

Electrical connection

Bearing» 1 VPP pin layout

Incremental
MRP 8081 Dplus

Shaft

15-pin D-sub connector

Hollow through shaft D = 100 mm1)

300 N (centered load)

1)

100 N

Max. permissible axial load

Max. permissible radial load1)

Power supply

Max. permissible tilting torque6 Nm

Contact stiffness

Axial: 684 N/µm
Radial: 367 N/µm
(calculated values)

Resistance to tilt

1250 Nm/mrad (calculated value)

Mech. permissible speed

300 rpm

Moment of friction≤ 0.2 Nm

Starting torque≤ 0.2 Nm1)

10 Nm

Moment of inertia of rotor

2.8 · 10

Radial guideway accuracy≤ 0.15 µm (measured at distance h = xx mm from the mating surface of the rotor2))

Non-reproducible radial
guideway accuracy≤ 0.20 µm (measured at distance h = xx mm from the mating surface of the rotor )Axial guideway accuracy≤ ±0.15 µm

Axial runout of the shaft≤ 4 µmWobble of the axis

0.5”

Vibration 55 Hz to 2000 Hz
Shock 6 ms

≤ 200 m/s (EN 60068-2-6)≤ 1000 m/s2 (EN 60068-2-27)(without load)3)

Other signals

4122

101

93

1114

7

5/6/8/15

UPSensor
UP0VSensor
0V

A+

A–

B+

B–

R+R–

Vacant1) Vacant1) Vacant

Brown/
GreenBlueWhite/
GreenWhiteBrown

GreenGrayPinkRedBlack/

13Violet/

Yellow

Cable shield connected to housing; UP = Power supply voltage
Sensor: The sense line is connected in the encoder with the corresponding power line.
Vacant pins or wires must not be used!

Max. transferable shaft torque–3

Incremental signalskgm22)

2

Protection EN 60529

IP20

Operating temperature
Storage temperature

0 °C to 50 °C
0 °C to 50 °C

Relative air humidity≤ 75 % without condensation

Mass

2.15 kg (without cable or connector)

1)

Purely static load, without additional vibrations or shock load
See the Measuring and bearing accuracy section in the Angle Encoder Modules brochure3)
When mounted2)

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

6Preliminary Product Information for the MRP 8081 Dplus  07/2023

1355159 · 01 · B · 02 · 07/2023 · 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.

Further information:
Comply with the requirements described in the following documents to ensure correctand intended operation.
• Brochure: Angle Encoder Modules						1102713-xx• Brochure: Interfaces of HEIDENHAIN Encoders			1078628-xx• Brochure: Cables and Connectors						1206103-xx