Endress and Hauser and Co NMR8XE User Manual

TI01252G/00/EN/02.16

Products Solutions Services

Technical Information

Micropilot NMR81

Tank Gauging

Application

Micropilot NMR8 Series intelligent tank gauges are designed for high accuracy liquid
level measurement in storage and process applications. They fulfill the exacting
demands of tank inventory management, inventory control, custody transfer, loss
control, total cost saving, and safe operation.

Typical areas of application

• Precise level measurement of oil (fuels), chemicals, and alcohol in free space

• Tank mounted intelligence makes NMR8x ideal for single or multi-task
installations, measuring the liquid level and integrating a wide range of tank
sensor measurement functions including: Liquid level, Water level, Temperature
and Pressure.

Your benefits

• SIL2/3 Certified (Min, Max, Continuous Level) (in preparation)

• Up to 6 SIL relay outputs

• Measures liquid level to an accuracy of +/- 0.5 mm (¹⁄₃₂ in)

• Wetted parts are completely separated from the electronic circuit

• Tank top mounting as small as 2"/DN50 flange

• Wide range of output signals including V1, Modbus RS 485, and HART protocol

• Suitable for atmospheric and high pressure applications up to 16 bar/

1.6 MPa (232 psi)

• Maintenance prediction of the instrument

• Integration of e.g. temperature, water level, pressure, overfill prevention sensor

• Direct connection of spot or average temperature sensor

• Robust IP66/68, NEMA Type 4x/6P enclosure

• Operation and display in a wide variety of local languages

Table of contents

Micropilot NMR81

Document information ....................... 3

Symbols .................................... 3

Function and system design ................... 5

Measuring principle ............................ 5

Integration of tank sensors ....................... 6

Measuring system ............................. 7

Input ..................................... 8

Measured variable ............................. 8

Maximum measuring range ...................... 8

Operating frequency ........................... 8

Transmitting power ............................ 8

HART Ex ia/IS active input ....................... 8

Output ................................... 9

I/O modules ................................. 9

"Modbus RS485": Technical data ................... 10

"V1": Technical data ........................... 11

"4-20mA HART" I/O module (Ex d/XP or Ex i/IS):

Technical data .............................. 11

"Digital I/O module": Technical data ................. 11

Power supply ............................. 12

Terminal assignment .......................... 12

Supply voltage .............................. 12

Cable entries ............................... 13

Cable specification ............................ 13

Overvoltage protection ......................... 13

Performance characteristics .................. 14

Reference operating conditions ................... 14

Measured value resolution ...................... 14

Maximum measured error ....................... 14

Hysteresis ................................. 14

Repeatability ............................... 14

Linearity .................................. 14

Long-term drift .............................. 14

Influence of ambient temperature ................. 14

Installation ............................... 15

Installation conditions ......................... 15

Environment .............................. 18

Ambient temperature range ..................... 18

Ambient temperature limits ..................... 18

Classification of environmental conditions according to

DIN EN 60721-3-4 ........................... 19

Storage temperature .......................... 19

Humidity .................................. 19

Degree of protection .......................... 19

Shock resistance ............................. 19

Vibration resistance ........................... 19

Electromagnetic compatibility (EMC) ............... 19

Process .................................. 20

Process temperature range ...................... 20

Process pressure range ......................... 20

Dielectric constant ............................ 20

Custody transfer approval ................... 21

Mechanical construction .................... 22

Dimensions ................................ 22

Weight ................................... 24

Materials .................................. 25

Operability ............................... 27

Operating concept ............................ 27

Operating options ............................ 27

Local operation .............................. 27

Remote operation ............................ 28

Operation via service interface .................... 28

Certificates and approvals ................... 29

CE mark ................................... 29

RCM-Tick marking ............................ 29

Ex approval ................................ 29

Dual seal according to ANSI/ISA 12.27.01 ............ 29

Functional Safety (SIL) ......................... 29

WHG ..................................... 29

Weight & Measure approval ..................... 29

Radio standard EN302372-1/2 ................... 29

FCC / Industry Canada ......................... 29

Non-ionizing radiation protection .................. 30

Test, certificate .............................. 30

Other standards and guidelines ................... 30

Ordering information ....................... 32

Ordering information .......................... 32

Calibration certificate .......................... 32

Customized parametrization ..................... 33

Marking .................................. 33

Application packages ....................... 34

Advanced tank measurement methods .............. 34

Accessories ............................... 37

Device-specific accessories ...................... 37

Communication-specific accessories ................ 39

Service-specific accessories ...................... 39

System components ........................... 39

Documentation ............................ 40

Technical Information (TI) ...................... 40

Brief Operating Instructions (KA) .................. 40

Operating Instructions (BA) ..................... 40

Description of Device Parameters (GP) ............... 40

Safety instructions (XA) ........................ 40

Registered trademarks ...................... 41

2 Endress+Hauser

Micropilot NMR81

DANGER

WARNING

CAUTION

NOTICE

Document information

Symbols

Safety symbols

Symbol Meaning

DANGER!

This symbol alerts you to a dangerous situation. Failure to avoid this situation will result in
serious or fatal injury.

WARNING!

This symbol alerts you to a dangerous situation. Failure to avoid this situation can result in
serious or fatal injury.

CAUTION!

This symbol alerts you to a dangerous situation. Failure to avoid this situation can result in
minor or medium injury.

NOTE!

This symbol contains information on procedures and other facts which do not result in
personal injury.

Electrical symbols

Symbol Meaning Symbol Meaning

Direct current Alternating current

Direct current and alternating current Ground connection

Protective ground connection

A terminal which must be connected
to ground prior to establishing any
other connections.

A grounded terminal which, as far as
the operator is concerned, is
grounded via a grounding system.

Equipotential connection

A connection that has to be connected
to the plant grounding system: This
may be a potential equalization line
or a star grounding system depending
on national or company codes of
practice.

Symbols for certain types of information

Symbol Meaning

Permitted

Procedures, processes or actions that are permitted.

Preferred

Procedures, processes or actions that are preferred.

Forbidden

Procedures, processes or actions that are forbidden.

Tip

Indicates additional information.

Reference to documentation

Reference to page

Reference to graphic

Visual inspection

Endress+Hauser 3

Symbols in graphics

,…,

.

Symbol Meaning

1, 2, 3 ... Item numbers

Series of steps

A, B, C, ... Views

A-A, B-B, C-C, ... Sections

Hazardous area

Indicates a hazardous area.

Safe area (non-hazardous area)

Indicates the non-hazardous area.

Micropilot NMR81

4 Endress+Hauser

Micropilot NMR81

D

R

f

t

1
2

f

2

f

1

Δt

Δ

f

Function and system design

Measuring principle

Micropilot is a directional level radar, operating based on the "Frequency-Modulated Continuous
Wave" principle (FMCW). The radar emits a precise crystal-oscillated, continuously varying frequency
wave from the antenna. The wave is reflected off the product surface and received again by the radar
system.

A0023768

1 FMCW principle: Emission and reflection of the continuous wave.



R Reference point of the measurement
D Distance between R and the product surface

The frequency of this wave is precisely modulated in the form of a sawtooth signal between two limit
frequencies f1 and f2:

A0023771



2 FMCW principle: Results of the frequency modulation

1 Emitted signal
2 Received signal

Thus, at any given time the frequencies of the emitted and the received signal differ by

Δf = k Δt

where Δt is the transit time and k is the known slope of the frequency modulation.

Δt, on the other hand, is determined by the distance D between the reference point R

and the

product surface:

D = (c Δt) / 2

where c is the speed of propagation of the wave.

In summary, D can be calculated from the measured frequency shift Δf. D is then used to calculate
the contents of the tank.

Endress+Hauser 5

Micropilot NMR81

3 3

4 4

2 2

1 1

HART 4-20 mA

A

B

HAR

T HART

5 5

Integration of tank sensors

In addition to measuring the level, the device can also be used for the integration of tank sensors
into tank inventory systems. All measured and calculated values can be displayed at the built-in
display. Via a field communication protocol, they can be transferred to an inventory control system.

A0023767

3 Integration of tank sensors with Micropilot (Example)



A HART multidrop mode
B HART and analog mode
1 Pressure transmitter
2 Average temperature transmitter
3 Micropilot
4 Field protocol transmits data to an inventory control system
5 Inventory control system (e.g. Tankvision NXA820 or Tankvision Professional NXA85)

6 Endress+Hauser

Micropilot NMR81

NXA820

NXA820

NXA820

NXA820

8

9

10

12

7

1

2

23

3 5 2 3

4 6

8

13

11

15

14

Measuring system

From single tank level measurement to the largest oil refinery applications, Endress+Hauser tank

•
gauging devices are an integral part of tank farm management solutions. A wide variety of data
output protocols are available for seamless integration into many commonly used systems.

• A primary example is Tankvision from Endress+Hauser. Tankvision is a scalable system offering
local tank management for multiple loops via Modbus or V1 protocols. Accumulated data is
available to DCS and other plant management systems via a Host Link.

A0027700

4 Integration of tank gauging devices into an inventory management system (typical example)



1 Proservo NMS8x
2 Pressure transmitter (e.g. Cerabar)
3 Temperature transmitter (e.g. Prothermo)
4 Tankside Monitor NRF81
5 Micropilot S FMR5xx
6 Micropilot NMR8x
7 Field protocol (e.g. Modbus, V1)
8 Tankvision Tank Scanner NXA820
9 Ethernet
10 Ethernet switch
11 Internet Browser
12 Tankvision Data Concentrator NXA821
13 Tankvision Host Link NXA822
14 Modbus
15 DCS or PLC

Endress+Hauser 7

Input

D

E

G

F

C

B

A

1

1

1

1

1

3

2

3

2

2 4

1

HR

CDI

WP

on

SIM

22334

4

112233445566778

8

POWER

i

E

1

1

2

CDI

D

C

1

2 3 4

1 2 3 4

Micropilot NMR81

Measured variable

Maximum measuring range

The measured variable is the distance between a reference point (mounting flange) and a reflective
surface (e.g. product surface).

The maximum measuring range depends on the dielectric constant

εr of the measured medium and

on the size of the antenna:

Dielectric constant ε

r

Antenna

50mm/2" 80mm/3" 100mm/4"

1.4 to 1.9 0.8 to 4 m (2.6 to 13 ft) 15 m (49 ft) 25 m (82 ft)

1.9 to 4 8 m (26 ft) 30 m (98 ft) 50 m (164 ft)

4 to 10 20 m (66 ft) 60 m (197 ft)

> 10 30 m (98 ft) 70 m (230 ft)

1) Feature 100 of the product structure
For devices with Weight+Measure approval: Maximum measuring range: 30 m (97 ft)

2)

1)

2)

2)

2)

70 m (230 ft)

70 m (230 ft)

2)

2)

For dielectric constants (DC values) of many media commonly used in various industries refer
to:

the Endress+Hauser DC manual (CP01076F)

•

• the Endress+Hauser "DC Values App" (available for Android and iOS)
For devices with Weight+Measure approval (option LK or LL of ordering feature 590

"Additional Approval"): Maximum measuring range:

0.8 to 30 m (2.6 to 97 ft)

The actual usable measuring range depends on additional criteria like the mounting location or
possible interference reflections.

Operating frequency

Transmitting power

HART Ex ia/IS active input

Device Operating frequency

NMR81 approx. 78 GHz

Device Peak pulse power Average output power

NMR81 6.3 mW 63 µW

5 HART Ex ia/IS active input



E1 HART +
E2 HART -

The device has a HART Ex ia/IS active input. Additional features are provided if the following
Endress+Hauser devices are connected:

Prothermo NMT

The measured level is transmitted to the Prothermo. Prothermo uses this level to calculate the
average temperature of the product.

A0027364

8 Endress+Hauser

Micropilot NMR81

E

G

F

1

1

1

1 3

2

2

2 4

HR

CDI

WP

on

SIM

POWER

i

D

C

B

A

1122334

4

112233445566778

8

D

E

F

C

B

A

1

1

1

1

3

2

2 4

1

HR

CDI

WP

on

SIM

22334

4

112233445566778

8

i

G

1

3

2

POWER

NMx8x - XX xx xxxxxx

...

040

NMx8x - xx XX xxxxxx

...

050

I/O modules

Output

6 Position of the I/O modules in the terminal compartment



The terminal compartment contains up to four I/O modules, depending on the order code.

• Modules with four terminals can be in any of these slots.

• Modules with eight terminals can be in slot B or C.
The exact assignment of the modules to the slots is dependent on the device version. For a

detailed description refer to the Operating Instructions of the device in question.
The following restrictions apply when selecting the modules:

•

The device may contain a maximum of four I/O modules.

• A maximum of two I/O modules with 8 terminals is possible.

A0027363

Ordering feature 040: "Primary Output"

Option Number of I/O modules Type of I/O module Number of terminals Technical data

A1 1 Modbus RS485 4 →  10

B1 1 V1 4 →  11

E1 1 4-20mA HART Ex d/XP 8 →  11

H1 1 4-20mA HART Ex i/IS 8 →  11

Ordering feature 050: "Secondary IO Analogue"

Option Number of I/O

A1 1 1 x "Ex d/XP 4-20mA HART + RTD input" 1 x 8 →  11

A2 2 2 x "Ex d/XP 4-20mA HART + RTD input" 2 x 8 →  11

B1 1 1 x "Ex i/IS 4-20mA HART+ RTD input" 1 x 8 →  11

B2 2 2 x "Ex i/IS 4-20mA HART+ RTD input" 2 x 8 →  11

C2 2 1 x "Ex i/IS 4-20mA HART + RTD input"

X0 0 none 0 -

modules

Type of I/O module Number of terminals Technical data

2 x 8 →  11

1 x "Ex d/XP 4-20mA HART + RTD input"

Endress+Hauser 9

Micropilot NMR81

NMx8x - xx xx XXxxxx

...

060

Ordering feature 060: "Secondary IO Digital Exd"

Option Number of I/O modules Type of I/O module Number of terminals Technical data

A1 1 1 x "2x relay + 2x discrete I/O" 1 x 4 →  11

A2 2 2 x "2x relay + 2x discrete I/O" 2 x 4 →  11

A3 3 3 x "2x relay + 2x discrete I/O" 3 x 4 →  11

B1 1 1x "Modbus RS485" 1 x 4 →  10

B2 2 1x "Modbus RS485"

1 x "2x relay + 2x discrete I/O"

B3 3 1x "Modbus RS485"

2 x "2x relay + 2x discrete I/O"

X0 0 none 0 -

2 x 4 →  10

3 x 4 →  10

11

→ 

→  11

"Modbus RS485": Technical data

No. of units Maximum 15 instruments per loop

Baud rate Selectable:

Parity Selectable:

Cable Three-wire cable with screening. The screening must be connected inside the housing.

Termination resistors To be set as required in specific environments

Topology • Serial bus

Transmission distance Maximum 1 200 m (3 900 ft) including limbs or branches;

Instrument address Each transmitter has an individual bus address configured in the software of the

Isolation Bus inputs are electrically isolated from the other electronics.

Error on alarm Error message classified according to NAMUR NE 107

600 bit/s

•

• 1 200 bit/s

• 2 400 bit/s

• 4 800 bit/s

• 9 600 bit/s

• 19 200 bit/s

• Odd

• Even

• None

Tree structure

•

branches under 3 m (9.8 ft) are negligible

transmitter.

10 Endress+Hauser

Micropilot NMR81

"V1": Technical data

"4-20mA HART" I/O module (Ex d/XP or Ex i/IS): Technical data

No. of units Maximum 10 instruments per loop

Baud rate 3 300

Parity Selectable:

Cable • Two-wire twisted pair; screening recommended

Termination resistors Not required

Topology • Serial bus

Transmission distance Maximum 6 000 m (19 700 ft)

Instrument address Each transmitter has an individual bus address configured in the software of the

Isolation Serial communication circuit isolated from other circuits

Error on alarm Error message classified according to NAMUR NE 107

No. of units Max. 6 instruments per loop

Baud rate 1 200

Cable Two-wire, twisted pair screened cable;

Topology • Serial bus

Transmission distance Maximum 1 200 m (3 900 ft)

Instrument address Each transmitter on a signal loop has an individual bus address. This is defined

Isolation Bus inputs are electrically isolated from the other electronics

Connection of a Prothermo
NMT

Connection of a RTD
temperature probe

Error on alarm Error message classified according to NAMUR NE 107

bit/s

• Odd

• Even

• None

• Two-wire unscreened

• Tree structure

transmitter.

bit/s

Core cross section: 0.2 to 2.5 mm2 (24 to 13 AWG)

• Tree structure

within the transmitter software and / or auxiliary configuration environment
such as host system or Field Communicator 475.

The measured level is transmitted to the Prothermo. Prothermo uses this level
to calculate the average temperature of the product.

3-wire or 4-wire connection

"Digital I/O module": Technical data

Output

250 V

DC

@ 2 A

AC

DC

AC

Relay switching power for resisitive load • 30 VDC

• 250 VDC @ 0.1 A

• 250 VAC @ 2 A

Input

Maximum pick-up voltage • 250 V

•

Minimum drop-out voltage • 25 V

• 5 V

Current consumption at maximum voltage • ≤ 1 mA (DC)

• ≤ 2 mA (AC)

Endress+Hauser 11

Terminal assignment

D

E

F

C

B

A

1

1

1

1

3

2

2 4

1

HR

CDI

WP

on

SIM

22334

4

112233445566778

8

i

D

E

F

C

B

A

1

1

1

1 3

2

2 4

1

HR

CDI

WP

on

SIM

22334

4

112233445566778

8

i

G

1

3

2

POWER

G

1

3

2

POWER

G1 L
G3 N

AC 85...264 V

Power supply

7 Terminal compartment (typical example) and ground terminals



Micropilot NMR81

A0026372

Supply voltage

Terminal area Module

Up to four I/O modules, depending on the order code →  9

•

A/B/C/D

Modules with four terminals can be in any of these slots.

• Modules with eight terminals can be in slot B or C.

The exact assignment of the modules to the slots is dependent on the device version. For



a detailed description refer to the Operating Instructions of the device in question.

E HART Ex i/IS interface

• E1: H+

• E2: H-

F Remote display (in preparation)

Power supply: 85 to 264 V

G

• G1: L

• G2: not connected

AC

• G3: N

Protective ground connection

A0018339

to 240 V

100

AC

12 Endress+Hauser

Micropilot NMR81

Cable entries

Ordering feature 090 "Electrical Connection"

A 7 x thread M20

B 7 x thread M25

C 7 x thread G1/2

D 7 x thread G3/4

E 7 x thread NPT1/2

F 7 x thread NPT3/4

1) Position 13 of the order code, e.g. NMx8x-xxxxxxxxxxxxA...

For the following devices with TIIS Ex d approval, cable glands are attached to the device (see
position 1 and 2 of the order code). These cable glands must be used.

Micropilot NMR81-TA...

•

• Micropilot NMR81-TC...

• Micropilot NMR81-TE...

Cable specification Terminals

Terminal Wire cross section

Signal and power supply

Spring terminals (NMx8x-xx1...)

•

• Screw terminals (NMx8x-xx2...)

Ground terminal in the terminal compartment max. 2.5 mm2 (13 AWG)

Ground terminal at the housing max. 4 mm2 (11 AWG)

1)

Cable entries (with blind plugs)

0.2 to 2.5 mm2 (24 to 13 AWG)

Overvoltage protection

Power supply line

Standard device cable is sufficient for the power line.

HART communication line

Standard device cable is sufficient if only the analog signal is used.

•

• Shielded cable is recommended if using the HART protocol. Observe the grounding concept of the

plant.

Modbus communication line

• Observe the cable conditions from the TIA-485-A, Telecommunications Industry Association.

• Additional conditions: Use shielded cable.

V1 communication line

• Two wire (twisted pair) screened or un-screened cable

• Resistance in one cable: ≤ 120 Ω

• Capacitance between lines: ≤ 0.3 µF

On the communication and power lines; according to IEC 60060-1 /DIN 60079-14:

kA, 8/20 μs, 10 pulses according to IEC 60060-1 / DIN 60079-14

10

Endress+Hauser 13

Performance characteristics

Micropilot NMR81

Reference operating conditions

Measured value resolution

Maximum measured error

Hysteresis

According to OIML R85 (2008)

•

Temperature: –25 to +55 °C (–13 to 131 °F)

• Atmospheric pressure

• Relative humidity (air): 65 % ±15 %

• Medium with good reflectivity and calm surface

• Signal beam hits the tank wall only at one side

• No major interference reflections inside the signal beam

≤ 0.1 mm

The following values are valid for a measuring distance up to

Ordering feature 150 "Accuracy, Weight + Measure Approval"

• NTA: Maximum Performance, NMi type approval (in preparation)

•

• NTC: Custody transfer type approval according to NMi (in preparation)

• PTC: Custody transfer type approval according to PTB (in preparation)

• ICR: Standard version, w/o calibration certificate

• ICW: Standard version, 3-point calibration certificate

• ICX: Standard version, 5-point calibration certificate

1) Position 21 to 23 in the order code (e.g. NMR8x-xxxxxxxxxxxxxxxxxxxxICR...)

0.2 mm

(0.004 in)

30 m (100 ft)

1)

PTA: Maximum Performance, PTB type approval (in preparation)

(0.008 in)

Maximum measured error

±0.5 mm (±¹⁄₃₂ in)

±1 mm (±¹⁄₁₆ in)

±1 mm (±¹⁄₁₆ in)

Repeatability

Linearity

Long-term drift

Influence of ambient temperature

(0.008 in)

0.2 mm

Within maximum measured error

Within the specified error of measurement

Within the specified accuracy according to OIML R85 (2008)

14 Endress+Hauser