SD198F/00/en

71000297

Functional safety manual

Liquicap M FMI51, FMI52Capacitance level measurement

For liquids with a 4...20 mA output signal

Application

Overfill protection or operating maximum/minimum

detection of all types of liquids in tanks to satisfy

particular safety system requirements to IEC 61508.

The measuring device fulfills the requirements

concerning

• Safety functions up to SIL 2

• Explosion protection due to intrinsic safety or

flameproof enclosure

• EMC to EN 61326 and NAMUR Recommendation

NE 21.

Your benefits

• Use for level monitoring up to SIL 2:

– independently assessed (Functional Assessment)

by exida.com as per IEC 61508

• Permanent automatic monitoring

• Continuous measurement

• Measurement is practically independent

of the product properties

• Measurement is also possible in the event

of foam or if the surface is moving

• Easy commissioning

Liquicap M

2

Table of contents

SIL declaration of conformity. . . . . . . . . . . . . . . . . . . . 3

Functional Assessment Report. . . . . . . . . . . . . . . . . . . 4

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Layout of the measuring system with Liquicap M . . . . 5

Measuring system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Safety function data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Supplementary device documentation . . . . . . . . . . . . . . . . . . . . . . 6

Settings and installation instructions . . . . . . . . . . . . . . 7

Installation instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Configuration instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Reference operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Maximum measured error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Device configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Device configuration with increased safety via the display . . . . . . . 8

Device configuration with increased safety via the ToF Tool . . . . . 9

Configuration instructions for the signal processing unit . . . . . . . 10

Response in operation and in event of failure . . . . . . 11

Operating life of electrical components . . . . . . . . . . . 11

Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Recurrent function tests of the measuring system . . . 12

Proof test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

PFDavg depending on the selected maintenance interval . . . . . . . 13

FMEDA Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Liquicap M

3

SIL declaration of conformity

SIL06003a_en

Exam

ple

Liquicap M

4

Functional Assessment Report

Summary

Liquicap M

5

Introduction

! Note!

General information on functional safety (SIL) is provided at www.de.endress.com/SIL

and in the specialized brochure CP002Z "Safety in the Process Industry – reducing risks with SIL"

Layout of the measuring system with Liquicap M

Measuring system The measuring system's devices are displayed in the following diagram (example).

L00-FMI5xxxx-14-00-06-en-004

The safety-related signal of Liquicap M is the analog output signal 4...20 mA. All safety functions solely refer

to this output. In addition, Liquicap M communicates via HART and contains HART commands with additional

diagnostic information.

Liquicap M generates an analog signal (4...20 mA) that is proportional to the level. This signal is sent to a

downstream logic unit (e.g. PLC, limit signal transmitter, etc.) and there it is monitored for:

– Overshooting or undershooting a specified level value or level range

– The occurrence of a fault (e.g. sensor error, sensor cable disconnection or short-circuit, supply voltage

failure).

For fault monitoring, the logic unit must recognize HI alarms (≥ 21.0 mA) and Low alarms (≤ 3.6 mA).

While configuring the transmitter and performing maintenance work on Liquicap M, alternative measures must

be taken to ensure the process safety.

ENDRESS + HAENDRESS + HAUSERUSERRMA 422RMA 422

TTransmitter powerransmitter powersupply unit e.g. RMA422supply unit e.g. RMA422or RN221Nor RN221N(communication resistor(communication resistorincluded)included)

CommuboxCommuboxFXA195FXA195

Operating andOperating anddisplay moduledisplay module

- FieldCare- FieldCare-- TToFoF TTool - FieldTool - FieldTooloolPackagePackage

Logic UnitLogic Unit(e.g. PLC)(e.g. PLC)

Liquicap M

6

The safety-related characteristic values determined only apply to the following versions:

• FMI51 FMI51-######A##1#

FMI51-######B##1#

• FMI52 FMI52-######A##1#

FMI52-######B##1#

# = All standard device versions permitted

A = FEI50H + display

B = FEI50H

Valid FW version (firmware): version V01.03.00 or higher

Valid HW version (hardware): version V02.00 or higher

Safety function data The mandatory settings and data for the safety function are based on the description on Page 6 ff. and the

Appendix on Page 11.

The reaction time of the measuring system in the activated SIL mode is ≤ 0.5 s.

! Note!

MTTR is set at 8 hours.

Supplementary device

documentation

# Warning!

The technical limit values, safety instructions, installation instructions and configuration instructions must be

observed in accordance with the documentation supplied with the device. The following table provides an

overview of the associated documentation and the documentation's contents for Liquicap M.

Documentation Contents Comment

Technical Information

TI401F

– Technical data – The documentation is also available via the

Internet.

See www.de.endress.com.

Operating Instruction

BA298F

– Identification

– Installation

– Wiring

– Operation

– Commissioning, description

– Maintenance

– Configuration examples

– Parameter description

– Troubleshooting

– Appendix: menus illustrated

– The documentation is available in hard copy or

is provided on the ToF Tool CD.

The CD is supplied with every device.

– The documentation is also available via the

Internet.

See www.de.endress.com.

Safety instructions

XA327F, XA328F, XA346F

Control Drawings

ZD220F, ZD221F

Certificates

ZE265F

– Safety instructions, installation

instructions and operating

instructions for devices that are

suitable for use in Ex-areas or as

overfill protection (WHG

(German Water Resources Act)).

– Select the desired explosion protection

or approval by means of Feature 10

"Certificates" in the order code.

The corresponding documentation

is provided with the device.

Liquicap M

7

Settings and installation instructions

Installation instructions Please refer to the Operating Instructions (BA) for information on how to install Liquicap M correctly.

As the application conditions affect the safety of the measurement, the instructions in the Technical

Information (TI) and the Operating Instructions (BA) must be observed.

The operator must check the suitability of the measuring device for the specific application.

Additional information is available from the Endress+Hauser Sales Centers.

" Caution!

A minimum input voltage (terminal voltage) of 13.5 V must be ensured when using the devices in a safety

function.

Configuration instructions The following conditions are permitted for devices used in a safety function:

• Local operation via display operating unit

• Remote operation via PC:

– with "ToF Tool – FieldTool Package" (graphic operating program for Endress+Hauser devices),

version V3.06 or higher

– Fieldcare, version V2.08.00 or higher

Please refer to the appropriate Operating Instructions (BA) for further information on the settings.

" Caution!

Changes to the measuring system and the system's settings after commissioning can impair the protective

function!

Prior to the locking sequence, check the following after entering all the parameters

1. the safety function (e.g. by means of the "Level Simulation" parameter or by approaching the level)

2. whether the level value currently displayed corresponds to the actual level

Reference operating

conditions

The following data refer to a rod probe with an active probe length of 1 m:

• Temperature = +20 °C ±5 °C

• Pressure = 1013 mbar abs. ±20 mbar

• Humidity = 65 % ±20 %

• Medium = tap water (Conductivity ≥180 μS/cm)

Maximum measured error • Linearity: 2 % (of the full scale value)

• Reproducibility: 0.25 %

Device configuration When using the device in PCT protective functions, the device configuration must meet two requirements:

1. Confirmation concept

Proven independent checking of the safety-related parameters input

2. Locking concept

Device locked after configuration completed

The following method for device configuration is available:

– Device configuration with increased safety (SIL/WHG mode)

! Note!

• Following a reset, the device has to be switched off and then switched on again.

• Due to the increased configuration safety, the following section illustrates the use of the "Device

configuration with increased safety" method when using the device in PCT protective systems.

Liquicap M

8

Device configuration

with increased safety

via the display

When the display is connected, the keys on the electronic insert are deactivated!

Locking

The device must be locked following a specified locking sequence.

1. In the first control menu (SAX02), the setting for output damping and the response of the current output

in the event of an error must be checked and confirmed directly.

2. In the second control menu (SAX03), the calibration of the device must be checked against the calibration

data of the user (noted previously).

3. Then the device can be switched to the SIL/WHG mode in the control menu (SAX04) but only if

confirmation was positive in the two previous configuration menus.

L00-FMI5xxxx-19-05-xx-en-015

A key symbol on the display indicates that the device is locked.

If the electronics are replaced, the complete locking routine has to be performed again by the user.

! Note!

The SIL/WHG mode is retained after a power failure!

Unlocking

If Liquicap M has been calibrated as per the Operating Instructions (BA),

security locking must be activated.

To do so, select the "Security settings" menu item from the main menu

(CX001).

L00-FMI5xxxx-19-05-xx-en-014

↵↑↑

CX001CX001main menumain menu

basic setupbasic setupsafety settingssafety settingslinearisationlinearisationoutputoutputdevice propertiesdevice properties

SAX02SAX02 SAX03SAX03 SAX04SAX04

↵↑ ↑ ↵↑ ↑ ↵↑ ↑

1.1. 2.2. 3.3.

safety settingssafety settings safety settingssafety settings safety settingssafety settings

operating mode: stoperating mode: standardandardoutput damping: 1.0soutput damping: 1.0soutput: maxoutput: maxpparameter ok.: yesarameter ok.: yes

cap. empty calibration: 0.00 pFcap. empty calibration: 0.00 pFvalue emptyvalue empty 0 %0 %cap. fullcap. full 104.00 pF104.00 pFvalue fullvalue full 100 %100 %pparameter ok.: yesarameter ok.: yes

calibration:calibration:calibration:calibration:

calibration:calibration:

operating mode: SIL/WHGoperating mode: SIL/WHGSILSIL operating mode: lockedoperating mode: lockedststatus: SIL/WHG lockedatus: SIL/WHG locked

A password is required for unlocking.

The release code (7452) must be entered directly in the

SAX04 menu "SIL operating mode".

L00-FMI5xxxx-19-05-xx-en-016

SAX04SAX04

↵↑ ↑

safety settingssafety settings

operating mode: SIL/WHGoperating mode: SIL/WHGSILSIL operating mode: lockedoperating mode: lockedststatus: SIL/WHG lockedatus: SIL/WHG locked

Liquicap M

9

Device configuration

with increased safety

via the ToF Tool

The configuration routine and locking process is the same as when making the settings via the display.

All relevant parameters are displayed on a screen page here however. As with the display, these also have to

be confirmed.

L00-FMIxxxxx-20-00-00-en-006

! Note!

When reading back the locking, the serial number on the operating tool must be checked against the serial

number of the device in question.

Liquicap M

10

L00-FMIxxxxx-20-00-00-en-002

L00-FMIxxxxx-20-00-00-en-004

Configuration instructions

for the signal processing unit

Configuration instructions when using the level sensor as the continuous measuring system

When using the level sensor as the continuous measuring system, the limit value determined appropriately

must be entered at the downstream limit monitor (logic unit).

All calibration and configuration work must be carried out as specified in the associated Operating Instructions.

Liquicap M

11

Response in operation and in event of failure

The behavior during operation and in the event of errors is described in the Operating Instruction BA298F.

Operating life of electrical components

In accordance with IEC 61508-2, experience shows that the useful operating life of electrical components is

between 8 and 12 years.

Repair

If a SIL-type Endress+Hauser device which was used in a protective function fails, the "Declaration of

contamination and cleaning" must be enclosed with a note specifying "Use as SIL device in a protective system"

when returning the defective device.

Liquicap M

12

Recurrent function tests of the measuring system

Safety functions must be checked and inspected at appropriate intervals.

We recommend you carry out the inspection at least once a year. The onus is on the owner-operator to select

the type of inspection and the time intervals in the specified period.

The inspection must be carried out in such a way that it is proven that the safety system (see Page 11,

section "PFDavg depending on the maintenance interval selected") functions perfectly in interaction with all the

components.

The following section describes the repeat testing procedure to uncover dangerous undetected device failures.

Proof test This test detects approx. 45 % of the possible dangerous undetected device failures.

L00-FMI5xxxx-05-06-xx-en-001

1. Check whether the level value displayed corresponds to the actual level.

2. Ensure that the level does not change while the proof test is being performed.

3. Unlocking (see Page 7, "Unlocking" section)

4. Activate the proof test either on the display or

using the operating tool.

5. The current output must be monitored using a current measuring

device (see the corresponding diagram).

6. The proof test lasts approx. 30 s and cannot be interrupted.

The current output returns to the current level value.

7. Locking (see Page 7, "Locking" section)

8. Once the proof test has been carried out, the results must be

documented and stored in a suitable manner.

L00-FMI5xxxx-19-05-xx-en-017

SAX06SAX06

↵↑↑

proof testproof test

proof test: offproof test: off

II[mA][mA]

22.022.0

20.020.0

16.816.8

13.613.6

10.410.4

7.27.2

4.04.0

LevelLevel[%][%]

120120

100100

8080

6060

4040

2020

00

Measured valueMeasured value

approx 30 sapprox 30 s

Liquicap M

13

Appendix

The specific safety-related characteristic values can be found in the Declaration of Conformity on Page 3.

PFDavg depending on the

selected maintenance interval

L00-FMI5xxxx-05-06-xx-en-003

# Warning!

During safety-related use of Liquicap M, the following sources of error must be ruled out:

• Solid and/or heavy build-up on the probe rod

• Corrosion or diffusion in the context of medium compatibility with regard to rod/rope material and coating

0.0 2.0 4.0 6.0 8.0 10.00.0 2.0 4.0 6.0 8.0 10.0

3.00E-033.00E-03

2.50E-032.50E-03

2.00E-032.00E-03

1.00E-031.00E-03

5.00E-045.00E-04

0.00E+000.00E+00

1.50E-031.50E-03

3.50E-033.50E-03

PFDaPFDavgvgP

FD

PF

Daa v

gvg

TTest interest intervvalal[y[yearears]s]

1oo1D structure1oo1D structure

Liquicap M

14

FMEDA Report

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rre

nt

3,6

mA

or

21

mA

. F

or

this

co

nfig

ura

tio

n t

he

fo

llow

ing

ta

ble

s s

ho

w

ho

w t

he

ab

ove

sta

ted

re

qu

ire

me

nts

are

fu

lfill

ed

.

Th

e f

ollo

win

g f

ailu

re r

ate

s d

o n

ot

inclu

de

fa

ilure

s r

esu

ltin

g f

rom

in

co

rre

ct

use

of

the

tra

nsm

itte

r,

in

pa

rtic

ula

r h

um

idity

en

teri

ng

th

rou

gh

in

co

mp

lete

ly

clo

se

d

ho

usin

gs

or

ina

de

qu

ate

ca

ble

fe

ed

ing

th

rou

gh

th

e P

G in

lets

.

1 T

ype B

com

ponent:

“Com

ple

x”

com

ponent

(usin

g m

icro

contr

olle

rs or

pro

gra

mm

able

lo

gic

); fo

r deta

ils see

7.4

.3.1

.3 o

f IE

C 6

1508-2

.

The d

ocum

ent

was p

repare

d u

sin

g b

est

effort

. T

he a

uth

ors

make n

o w

arr

anty

of

any k

ind a

nd s

hall

not

be lia

ble

in

any e

vent

for

incid

enta

l or

consequential dam

ages in c

onnection w

ith t

he a

pplic

ation o

f th

e d

ocum

ent.

© A

ll rights

on t

he f

orm

at

of

this

technic

al re

port

reserv

ed.

Failu

re M

od

es, E

ffects

an

d D

iag

no

sti

c A

naly

sis

Pro

ject:

Liq

uic

ap

M F

MI

51

/52

with

4..

20

mA

ou

tpu

t F

EI5

0H

T

ran

sm

itte

r fo

r co

ntin

uo

us c

ap

acita

nce

le

ve

l m

ea

su

rem

en

t A

pp

lica

tio

ns w

ith

le

ve

l lim

it d

ete

ctio

n (

MIN

/ M

AX

de

tectio

n)

Cu

sto

me

r:

En

dre

ss+

Ha

use

r G

mb

H+

Co

. K

G

Ma

ulb

urg

G

erm

an

y

Co

ntr

act

No

.: E

+H

03

/03

-22

R

ep

ort

No

.: E

+H

03

/03

-22

R0

27

Ve

rsio

n V

1,

Re

vis

ion

R5

, F

eb

rua

ry 2

00

7

Ste

ph

an

Asch

en

bre

nn

er

Liquicap M

15

R5-ManagementSummary

R5-ManagementSummary

© e

xid

a.c

om

Gm

bH

e+

h 0

3-0

3-2

2 r

027 v

1 r

5.d

oc,

Febru

ary

1,

2007

Ste

phan A

schenbre

nner

Page 4

of

4

It i

s i

mp

ort

an

t to

re

aliz

e t

ha

t th

e “

no

eff

ect”

fa

ilure

s a

nd

th

e “

an

nu

ncia

tio

n”

failu

res a

re in

clu

de

d

in t

he

“sa

fe u

nd

ete

cte

d”

failu

re c

ate

go

ry a

cco

rdin

g t

o I

EC

61

50

8.

No

te t

ha

t th

ese

fa

ilure

s o

n its

o

wn

w

ill n

ot

aff

ect

syste

m re

liab

ility

o

r sa

fety

, a

nd

sh

ou

ld n

ot

be

in

clu

de

d in

sp

uri

ou

s tr

ip

ca

lcu

latio

ns.

Th

e fa

ilure

ra

tes a

re va

lid fo

r th

e u

se

ful

life

o

f L

iqu

ica

p M

FM

I 5

1/5

2 w

ith

4..

20

mA

ou

tpu

t F

EI5

0H

(se

e A

pp

en

dix

3).

© e

xid

a.c

om

Gm

bH

e+

h 0

3-0

3-2

2 r

027 v

1 r

5.d

oc,

Febru

ary

1,

2007

Ste

phan A

schenbre

nner

Page 3

of

4

Th

e lis

ted

fa

ilure

ra

tes a

re va

lid fo

r o

pe

ratin

g str

ess co

nd

itio

ns ty

pic

al

of

an

in

du

str

ial

fie

ld

en

vir

on

me

nt

sim

ilar

to I

EC

60

65

4-1

cla

ss C

(sh

elte

red

lo

ca

tio

n)

with

an

ave

rag

e t

em

pe

ratu

re

ove

r a

lo

ng

pe

rio

d o

f tim

e o

f 4

0ºC

. F

or

a h

igh

er

ave

rag

e t

em

pe

ratu

re o

f 6

0°C

, th

e f

ailu

re r

ate

s

sh

ou

ld b

e m

ultip

lied

with

an

exp

eri

en

ce

ba

se

d f

acto

r o

f 2

,5.

A s

imila

r m

ultip

lier

sh

ou

ld b

e u

se

d

if f

req

ue

nt

tem

pe

ratu

re f

luctu

atio

n m

ust

be

assu

me

d.

Tab

le 1

: S

um

mary

– F

ailu

re r

ate

s

Fa

ilu

re c

ate

go

ry

Fa

ilu

re r

ate

s (

in F

IT)

Fa

il D

an

ge

rou

s D

ete

cte

d

69

5

F

ail

de

tecte

d (

int.

dia

g.)

6

28

F

ail

low

(d

ete

cte

d b

y t

he

lo

gic

so

lve

r)

39

F

ail

Hig

h (

de

tecte

d b

y t

he

lo

gic

so

lve

r)

28

Fa

il D

an

ge

rou

s U

nd

ete

cte

d

75

No

Eff

ect

11

6

An

nu

ncia

tio

n U

nd

ete

cte

d

2

No

t p

art

1

11

Ta

ble

2 F

ail

ure

ra

tes

ac

co

rdin

g t

o IE

C 6

15

08

sd

su

2

dd

du

SF

F

DC

S 3

D

CD 3

0 F

IT

11

8 F

IT

69

5 F

IT

75

FIT

9

1%

0

%

90

%

Tab

le 3

: S

um

mary

– P

FD

AV

G v

alu

es / P

FH

va

lues

T

[Pro

of]

= 1

ye

ar

T[P

roo

f] =

5 y

ea

rs

T[P

roo

f] =

10

ye

ars

PF

H =

7,5

1E

-08

1/h

4

PF

DA

VG =

3,2

9E

-04

P

FD

AV

G =

1,6

4E

-03

P

FD

AV

G =

3,2

8E

-03

Th

e b

oxe

s m

ark

ed

in

gre

en

(

)

me

an

th

at

the

ca

lcu

late

d P

FD

AV

G /

PF

H v

alu

es a

re w

ith

in t

he

a

llow

ed

ra

ng

e f

or

SIL

2 a

cco

rdin

g t

o t

ab

le 2

/ 3

of

IEC

61

50

8-1

an

d d

o f

ulfill

th

e r

eq

uir

em

en

t to

n

ot

cla

im

mo

re

tha

n

35

%

of

this

ra

ng

e,

i.e

. to

b

e

be

tte

r th

an

o

r e

qu

al

to

3,5

0E

-03

o

r 3

,50

E-0

7 1

/h,

resp

ective

ly.

Be

ca

use

th

e

Sa

fe

Fa

ilure

F

ractio

n

(SF

F)

is

ab

ove

9

0%

, a

lso

th

e

arc

hite

ctu

ral

co

nstr

ain

ts

req

uir

em

en

ts o

f ta

ble

3 o

f IE

C 6

15

08

-2 f

or

Typ

e B

su

bsyste

ms w

ith

a H

ard

wa

re F

au

lt T

ole

ran

ce

(H

FT

) o

f 0

are

fu

lfill

ed

.

A u

se

r o

f th

e t

ran

sm

itte

r fo

r co

ntin

uo

us c

ap

acita

nce

le

ve

l m

ea

su

rem

en

t L

iqu

ica

p M

FM

I 5

1/5

2

with

4..

20

mA

ou

tpu

t F

EI5

0H

ca

n u

tiliz

e t

he

se

fa

ilure

ra

tes i

n a

pro

ba

bili

stic m

od

el

of

a s

afe

ty

instr

um

en

ted

fu

nctio

n (

SIF

) to

de

term

ine

su

ita

bili

ty i

n p

art

fo

r sa

fety

in

str

um

en

ted

syste

m (

SIS

) u

sa

ge

in

a

p

art

icu

lar

sa

fety

in

teg

rity

le

ve

l (S

IL).

A

fu

ll ta

ble

o

f fa

ilure

ra

tes is

p

rese

nte

d in

se

ctio

n 5

.2 a

lon

g w

ith

all

assu

mp

tio

ns.

2 N

ote

that

the S

U c

ate

gory

inclu

des f

ailu

res t

hat

do n

ot

cause a

spurious t

rip

3 D

C m

eans t

he d

iagnostic c

overa

ge (

safe

or

dangero

us).

4 T

he P

FH

valu

e i

s b

ased o

n a

fault d

ete

ction a

nd r

eaction t

ime o

f 40 m

inute

s.

This

als

o r

equires t

hat

a c

onnecte

d

logic

solv

er

can d

ete

ct

“fail

low

” and/o

r “f

ail

hig

h”

failu

res w

ithin

a t

ime t

hat

allo

ws t

o r

eact

within

the p

rocess s

afe

ty

tim

e.

Liquicap M

Instruments International

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