Endress+Hauser Liquisys M CPM 223 User manual

BA 194C/07/en/05.99
No. 51500268
Software version 2.0 or later Liquisys M
CPM 223 / 253
Transmitter for
pH and ORP
Operating Instructions
Endress Hauser
The Power of Know How
Quality made by
Endress+Hauser
ISO 9001
ENDRESS+HAUSER
LIQUISYS M
ENDRESS+HAUSER
LIQUISYS M

Need information on the instrument?
Please read the following chapters:
Safety
General information
You wish to install the instrument.
The required steps are described in this chapter:
Installation
You wish to operate or reconfigure the instrument.
The operating concept is explained in these chapters:
Operation
Instrument configuration
Interfaces
Need help with problems or maintenance?
Diagnosis Maintenance
Appendix
Technical data
Accessories
Index
%
Ω
°C

PM253E00.CHP
Table of contents
1 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1 Symbols used ............................................................. 2
1.2 Storage and transport ....................................................... 2
1.3 Unpacking ................................................................ 2
1.4 Packaging and disposal ..................................................... 2
1.5 Product structure ........................................................... 3
2 Safety............................................................... 4
2.1 Intended application ........................................................ 4
2.2 General safety instructions ................................................... 4
2.3 Installation, start-up, operation ................................................ 4
2.4 Monitoring and safety features ................................................ 5
2.5 Immunity to interference ..................................................... 5
2.6 Certificate of conformity ...................................................... 5
3 Installation........................................................... 6
3.1 Measuring system .......................................................... 6
3.2 Dimensions ............................................................... 7
3.3 Mounting ................................................................. 8
3.4 Electrical connection ....................................................... 12
3.5 Electrode installation and measuring cable connection ............................ 14
4 Operation........................................................... 17
4.1 Operator interface ......................................................... 17
4.2 Display .................................................................. 17
4.3 Key functions ............................................................. 18
4.4 Auto / manual mode of operation.............................................. 19
4.5 Operating concept......................................................... 20
4.6 Access codes ............................................................ 22
4.7 Display during measurement................................................. 22
4.8 Calibration ............................................................... 22
5 Instrument configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.1 Start-up ................................................................. 25
5.2 System configuration ....................................................... 25
5.3 Current outputs ........................................................... 27
5.4 Monitoring functions........................................................ 29
5.5 Relay contact configuration .................................................. 33
5.6 Service .................................................................. 45
5.7 E+H Service .............................................................. 46
5.8 Interfaces ................................................................ 47
5.9 Calibration ............................................................... 47
5.10 Offset ................................................................... 51
6 Interfaces........................................................... 52
7 Maintenance and troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
7.1 Definition of terms ......................................................... 53
7.2 Safety instructions ......................................................... 53
7.3 Troubleshooting common problems ........................................... 53
7.4 Problem elimination based on error messages ................................... 56
8 Diagnosis and corrective maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
8.1 Definition of terms ......................................................... 58
8.2 Safety instructions ......................................................... 58
8.3 Diagnosis ................................................................ 58
8.4 Corrective maintenance of Liquisys M CPM 223.................................. 60
8.5 Corrective maintenance of Liquisys M CPM 253.................................. 62
8.6 Spare parts orders ......................................................... 64
8.7 Service equipment “optoscope” .............................................. 64
8.8 Corrective maintenance of measuring system ................................... 65
9 Accessories ......................................................... 66
10 Technical data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
11 Appendix........................................................... 71
12 Index............................................................... 75
Liquisys M CPM 223 / 253
Endress+Hauser 1

1 General information
1.1 Symbols used
Warning:
This symbol alerts to hazards which
may cause serious injuries as well as
damage to equipment if ignored.
Note:
This symbol indicates important
items of information.
Ignoring this information may result
in malfunction.
1.2 Storage and transport
The packaging material used to store or
transport the transmitter must provide shock
protection. Optimal protection is provided by
the original packaging materials.
Conformance with the ambient conditions
(see Technical data) must be assured.
1.3 Unpacking
Verify that the packaging and contents are
undamaged! Inform the post office or freight
carrier of any damage.
Damaged merchandise must be retained until
the matter has been settled.
Check that the delivery is complete and
agrees with the shipping documents and your
order (refer to nameplate for type and
variant).
The delivery includes:
•Measuring transmitter CPM 223 or
CPM 253
•Operating instructions BA 194C/07/en
•Field instrument:
- 1 plug-in screw terminal
- 1 cable gland Pg 7
- 1 cable gland Pg 16, reduced
- 2 cable glands Pg 13.5
•Panel-mounted instrument:
- 1 set of plug-in screw terminals
- 2 fastening clips
- 1 BNC connector
Keep the original packaging materials for
future storage or shipping of the instrument.
If you have any questions, consult your
supplier or the Endress+Hauser sales agency
in your area (see back cover of these
operating instructions for addresses).
1.4 Packaging and disposal
Package the assembly properly for reuse at a
later point in time. Optimal protection is
provided by the original packaging materials.
Observe local regulations for disposal.
General information Liquisys M CPM 223 / 253
2Endress+Hauser

1.5 Product structure
You can identify the instrument version by the
order code on the nameplate.
131085-4B
ENDRESS+HAUSER
LIQUISYS-M
order code / Best.Nr.
serial no. / Ser.-Nr. /Codes:
:
:
:
:
:
:
:
:
:
prot. class / Schutzart
ambient temp. / Umgebungstemperatur
output 1 / Ausgang 1
output 2 / Ausgang 2
mains / Netz
measuring range / Messbereich
temperature / Temperatur
pH / Redox
pH 0 ... 14 +/–1500 mV
–10 ... 125 °C
–10 ... + 55 °C
0/4 ... 20 mA
230 VAC
276944
7,5 VA
IP 65
50 / 50 Hz
0/4 ... 20 mA
CPM 253-PS1515
253-TYP.CDR
131085-4B
ENDRESS+HAUSER
LIQUISYS-M
order code / Best.Nr.
serial no. / Ser.-Nr. /Codes:
:
:
:
:
:
:
:
:
:
prot. class / Schutzart
ambient temp. / Umgebungstemperatur
output 1 / Ausgang 1
output 2 / Ausgang 2
mains / Netz
measuring range / Messbereich
temperature / Temperatur
pH / Redox
pH 0 ... 14 +/–1500 mV
–10 ... 125 °C
–10 ... + 55 °C
0/4 ... 20 mA
230 VAC
276944
7,5 VA
IP 54 / IP 30
50 / 50 Hz
0/4 ... 20 mA
CPM 223-PR0110
223-TYP.CDR Fig. 1.1
left:
Nameplate of
CPM 253
right:
Nameplate of
CPM 223
Liquisys M CPM 223 / 253
Version
PR pH/redox measurement
PS pH/redox measurement
with additional functions (S version)
Power supply
0230VAC
1115VAC
5100VAC
8 24 V AC/DC
Measurement output
0 pH / redox
1 pH / redox and temperature
3 Profibus PA
5 pH / redox with Hart
6 pH / redox, Hart and temperature
Contacts
05 no additional contacts
10 2 contacts (limits / PID / timer)
15 4 contacts (limits / PID / timer / Chemoclean)
16 4 contacts (limits / PID / timer)
CPM223-
complete order code
CPM253-
PM253E01.CHP
Liquisys M CPM 223 / 253 General information
Endress+Hauser 3

2 Safety
2.1 Intended application
The CPM 223/253 transmitter is a field-tested
and reliable measuring transmitter used to
determine the pH or redox (ORP) value.
The CPM 223/253 is particularly suitable for
use in the following areas of application:
•Chemical industry
•Pharmaceutical industry
•Foodstuffs industry
•Drinking water processing
•Condensate processing
•Municipal sewage treatment plants
•Water conditioning
•Electroplating
2.2 General safety instructions
This device has been manufactured for safe
operation according to the state of the art in
engineering and conforms to the applicable
regulations and European standards (see
Technical data). It has been designed
according to EN 61010-1 and has left the
manufacturer’s works in perfect condition.
However, if used improperly or for purposes
other than the intended purpose, it may be
dangerous, e.g. due to incorrect connection.
Warning:
•Operating this instrument in any
way other than as described in
these instructions may compromise
the safety and function of the
measuring system and is therefore
impermissible.
•The notes and warnings in these
installation and operating
instructions must be strictly
adhered to!
2.3 Installation, start-up, operation
Warning:
•This device may only be installed,
connected electrically,
commissioned, operated and
serviced by properly trained
personnel authorized by the
system operator.
•The personnel must be familiar
with these operating instructions
and must adhere to the
instructions described therein.
•Make sure that the power supply
ratings match the data specified
on the nameplate before you
connect the instrument to a power
source.
•A clearly identified mains
disconnecting device must be
installed close to the instrument.
•Live components can be touched
through the vent slots in the
housing and the openings on the
rear of the housing. Do not insert
tools, wires, etc., in these slots
(CPM 223 only).
•Check that all connections have
been properly made before
powering up the system!
•Damaged equipment that may be
dangerous must not be operated
and should be clearly identified as
being defective.
•Any troubleshooting of the
measuring system is to be
performed exclusively by
authorized, trained personnel.
•If faults cannot be remedied, the
instrument must be removed from
service and secured to prevent
accidental start-up.
•Repairs not described in these
operating instructions may only be
performed at the manufacturer’s
works or by the Endress+Hauser
Service Organization.
Safety Liquisys M CPM 223 / 253
4Endress+Hauser

2.4 Monitoring and safety features
Safety features
The transmitter is protected against external
influences and damage by the following
design measures:
•Rugged housing
•Degree of protection provided by
enclosure: IP 65 (CPM 253)
•UV resistance
Monitoring features
In the event of a system error or power failure,
an alarm condition is signalled via a fault-
signalling contact.
2.5 Immunity to interference
This instrument has been tested according to
the applicable European standards for
industrial applications with regard to
electromagnetic compatibility. It is protected
against electromagnetic interference by the
following design measures:
•Cable screen
•Interference suppressor filter
•Interference suppression capacitors
Warning:
The specified immunity to
interference only applies for devices
connected as outlined in these
operating instructions.
2.6 Certificate of conformity
The CPM 223/253 transmitter has been
developed and manufactured in accordance
with currently valid European standards and
directives.
Note:
An EC certificate of conformity is
supplied.
PM253E02.CHP
Liquisys M CPM 223 / 253 Safety
Endress+Hauser 5

3 Installation
The following procedure should be followed
for a complete measuring system installation:
•Installation or attachment of transmitter
(see chapter 3.3)
•Selection and connection of cable and
electrode (see chapters 3.4, 3.5 and 9)
•Installation is followed by start-up (see
chapter 5)
3.1 Measuring system
The complete measuring system comprises:
•The Liquisys M CPM 223 or CPM 253
transmitter
•A pH or redox electrode with or without
an integrated temperature sensor
•An immersion or flow assembly
•A pH measuring cable (e.g. CPK 7)
Optional:
•Extension cable
•Junction box VBA or VBM
ENDRESS+HAUSER
LIQUISYS
CAL REL
REL1
REL1
ALARM
REL2
REL2
E
ENDRESS+HAUSER
LIQUISYS
CAL REL
REL1
REL1
ALARM
REL2
REL2
E
PM253SYS.CDR
Immersion
assembly CPA 111
Flow assembly
CPA 250
Electrode, e.g. OrbiSint W
CPS 11 with integrated
Pt 100
Retractable
assembly
CPA 450
Junction box VBA
Liquisys M CPM 253
Measuring cable
e.g. CPK 7
Liquisys M CPM 223
Fig. 3.1
Complete measuring
systems
The examples show
Liquisys M CPM 253 with
measuring cable,
assembly and pH or
redox electrode, and
Liquisys M CPM 223 with
assembly and pH or
redox electrode
Installation Liquisys M CPM 223 / 253
6Endress+Hauser

3.2 Dimensions
ENDRESS+HAUSER
LIQUISYS
CAL REL
REL 1
REL 1
ALARM
REL 2
REL 2
E
FELD1.CDR
11
170
247
115
∅6
157
154
70
70
Fig. 3.2
Dimensions of Liquisys M
CPM 253
FELD2.CDR
1
2
3
4
Fig. 3.3
Inside of housing of
Liquisys M CPM 253:
1 Removable
electronics box
2 Partition plate
3 Terminal blocks
4 Fuse
GEHAEUS1.CDR
PM253E03.CHP
Liquisys M CPM 223 / 253 Installation
Endress+Hauser 7

3.3 Mounting
3.3.1 Field instrument
Several mounting options are available for the
Liquisys M in the field instrument version:
•Post mounting on cylindrical pipes
•Post mounting on a square post
•Wall mounting with fastening screws
Weather protection cover CYY 101 can be
used for outdoor installation in conjunction
with all mounting variants.
Weather protection cover CYY 101
Weather protection cover for outdoor
installation, to be mounted on field instrument;
material: 1.4301 (SS 304);
order no.: CYY101-A
EINBAU2.CDR
96
6
139
90
Fig. 3.4
Liquisys M CPM 223,
panel-mounted version
DACH.CDR
300
270
320
Fig. 3.5
Weather protection cover
for field instruments
EINBAU1.CDR
Installation Liquisys M CPM 223 / 253
8Endress+Hauser

Post mounting kit
Mounting kit for installation of field housing on
horizontal or vertical pipes (max. ∅60 mm);
material: stainless steel VA;
order no.: 50086842
Universal mounting post CYY 102
Square tube for mounting of measuring
transmitters; material: 1.4301 (SS 304);
order no.: CYY102-A
MONT5.CDR
60
90
70
∅6
70
∅8
70
90
M6
∅8
30
90
60 x 60
1495
150
120
∅max. 60
Fig. 3.6
left:
Mounting kit for post
mounting on cylindrical
pipes
right:
Square mounting post
PM253E03.CHP
Liquisys M CPM 223 / 253 Installation
Endress+Hauser 9

3.3.2 Mounting examples
MONT10.CDR
Fig. 3.7
Pipe mounting of Liquisys
M field instrument
MONT2.CDR
Fig. 3.8
Liquisys M field instrument
left:
Wall mounting
right:
Mounting with universal
post and weather
protection cover
Installation Liquisys M CPM 223 / 253
10 Endress+Hauser

3.3.3 Panel-mounted instrument
The instrument is attached using the supplied
tensioning screws (see Fig. 3.9).
The required overall installation depth is
approx. 165 mm.
MONT9.CDR
92+0.5
92+0.5
90
57
33
approx.
25
max. 45
96
92
1
2
3
139 6
Fig. 3.9
Attachment of panel-
mounted instrument
1 Wall of control
cabinet
2 Gasket
3 Tensioning screws
PM253E03.CHP
Liquisys M CPM 223 / 253 Installation
Endress+Hauser 11

3.4 Electrical connection
Connection diagram
The connection diagram depicted in Fig. 3.10
shows the connections of an instrument
equipped with all the options. The connection
of the various electrodes with the measuring
cables is shown in more detail in Figs. 3.13
to 3.19.
pH
Ref.
11
12
13
47
48
49
57
58
59
51
52
53
54
55
56
PA/
PM
15 V
85
86
S
10-50 V
81
93
82
94
10-50 V
L+
L-
L
N
∼=
41
42
43
pH
mA
31
32
mA
33
34
ANPH01.CDR
Aux. voltage
output
Digital
input 2
(Chemoclean)
Digital
input 1
(hold)
Signal output 2:
temperature
Signal output 1
pH / redox
Temperature
Electrode
Alarm
(de-energized
contact
position)
Relay 1
(de-energized
contact
position)
Relay 2
(de-energized
contact
position)
Relay 3
(de-energized
contact
position)
Relay 4
(de-energized
contact
position)
Mains
*optional
**
gn
wt
ye
Fig. 3.10
Electrical connection of
Liquisys M CPM 223/253
(all inputs and outputs
connected)
Installation Liquisys M CPM 223 / 253
12 Endress+Hauser

Connections of field instrument
For connection, the measuring cables are
introduced through the cable glands on the
field instrument and connected according to
the diagrams in Figs. 3.10, 3.11 and 3.12.
Connections of panel-mounted instrument
AN-PH01.CDR Fig. 3.11
Connection compartment
sticker for field instrument
REL1
REL2
REL3
REL4
NC
NC
49
COM
COM
COM
COM
59
54
55
56
52
51
53
58
57
48
47
131084-4B
AN-PH02.CDR Fig. 3.12
Connection compartment
sticker for panel-mounted
instrument
PM253E03.CHP
Liquisys M CPM 223 / 253 Installation
Endress+Hauser 13

3.5 Electrode installation and measuring cable connection
Measuring cable connection
The pH and redox electrodes are connected
using special terminated and shielded
multi-core cables.
The measuring cables (see table) can be
extended with junction box VBA or VBM (see
chpt. 9). Termination instructions are supplied
with the measuring cables.
Note:
Connectors, cable ends and
terminals are to be protected against
moisture to prevent inaccurate
measurement!
Structure and termination of measuring cables
Special measuring cables required for connection of pH / redox electrodes
Electrode type Cable Extension
Electrode without temperature
sensor Pt 100 CPK 1 VBA / VBM box + CYK 71 cable
Electrode with temperature sensor
Pt 100 CPK 7 VBA / VBM box + CYK 71 cable
Single pH electrode
with reference electrode and
separate temperature sensor
CPK 2 VBA / VBM box
+ PMK cable
Maximum cable length
For pH / redox max. 50 m with CYK 71 cable
CPK127.CDR
CPK 1
CPK 2
CPK 7
PM
pH or
ORP
Outer screen
Pt 100 Pt 100
Ref.
pH or ORP
Coax bk
bn
Outer screen
gn
wt
ye
PA / PM
User must terminate end of CPK 2 cable!
bn
rd/bl
PMC
pH or redox
PMC
pH or redox
Ref. or redox
Pt 100
PM
pH + Pt 100
Coax bk
gn
bn
wt
ye
Outer screen
11
12
13
11
12
13
Reference or redox
(red inner cond.)
Fig. 3.13
Construction of special
measuring cables
CPK 1, CPK 2, CPK 7
Installation Liquisys M CPM 223 / 253
14 Endress+Hauser

Cable termination for panel-mounted instrument CPM 332 with screwed BNC connector
1. Cut off wire end sleeves of the coaxial
cable.
2. Insert cable gland (➀) and washer (➁)on
cable, remove inner insulation (13 mm), then
screw clamping ring (➂) onto insulation.
Please note: Parts ➀to ➂are supplied for
cable diameters of 3.2 mm and 5 mm.
3. Fold braided screen (➃) of screen back
over clamping ring and cut off excess
material.
4. Strip the black semiconductor layer to the
screen (reference signal).
5. Remove inner insulation (4 mm).
Use the supplied end sleeves (⑨) for the
stranded inner conductor. When using a
cable of another manufacturer use the end
sleeves only in case of single stranded
conductors.
6. Push BNC connector shell (➄) over the
cable (inner conductor must be located in
clamping notch (➅) in the connector pin).
Tighten cable gland (➀).
Clamp the inner conductor in the notch by
inserting the clamping piece (➆)and
screwing on the cover (➇), thereby
establishing proper contact.
Connection examples
Choice: symmetrical or asymmetrical?
The pH and redox electrodes can be
connected in either a symmetrical or an
asymmetrical configuration. General rule:
•Potential matching connection does not
exist –asymmetrical connection
(Figs. 3.18 and 3.19).
•Potential matching connection exists –
symmetrical connection
(Figs. 3.18 and 3.19).
However, which arrangement to use may also
depend on operating conditions.
CPK1.CDR
Outer
insulation
Outer screen
(to PE)
Inner screen
(ref.)
Coax
(pH / mV)
Litz wire bn
Fig. 3.14
Cable CPK 1:
Instrument connection
semiconductor layer
KABEL.CDR Fig. 3.15 Coaxial cable construction
13
16
4
➁➀
➂
➃
BNC1NEU.CDR
⑨
Fig. 3.16
Termination of
pH connecting line
for installation of BNC
elbow plug
➄
➀
➆
➅
➇
BNC2NEU.CDR Fig. 3.17
Installation of terminated
pH connecting line
in BNC elbow plug
PM253E03.CHP
Liquisys M CPM 223 / 253 Installation
Endress+Hauser 15

Note:
•The instrument is pre-configured
for symmetrical measurement.
Change the configuration in field
A2 for asymmetrical measurement
(see chapter 5.2.1).
•The conductor for the potential
matching pin must be connected
to the “PA/PM”terminal of the
instrument for symmetrical
measurement.
•If the software setting
“asymmetrical”is chosen for a
symmetrical connection, this will
reduce the service life of the
reference electrode.
•The instrument is approved for
protection class II and is generally
connected without protective earth.
•Cable termination is only
required for CPM 223!
ϑ ϑ
SNC NC S
CPK 7 CPK 7
PH-AN01.CDR
11 12 13 11 12 13
Screen
Screen
wtgn ye bk
PA/
PM PA/
PM
BNC
gn wt ye bk
bn
bn
bn
BNC
Potential matching pin
(PM/PMC)
Ref Ref
bn
Fig. 3.18
pH electrode connection
to Liquisys M
CPM 223 / 253
Left:
Asymmetrical (without PMC)
Right:
Symmetrical (with PMC)
SS NC NC
PA/
PM PA/
PM
bk
Screen
CPK 7 CPK 7
bn bk
Screen
bn
bn
Potential matching pin
(PM/PMC)
pH/
mV Ref. Ref.
pH/
mV
RED-AN01.CDR
bn bk
BNC BNC
Panel-mounted
instrument Field
instrument Panel-mounted
instrument Field
instrument
Fig. 3.19
ORP electrode connection
to Liquisys M
CPM 223 / 253
Left:
Asymmetrical (without PMC)
Right:
Symmetrical (with PMC)
Installation Liquisys M CPM 223 / 253
16 Endress+Hauser

4 Operation
4.1 Operator interface
4.2 Display
LED indicators
Liquid crystal display
705 pH
R262
Setpoint
DISPL1-E.CDR
Liquid crystal display
for display of measured
values and
configuration data
4 main control keys for
calibration and
instrument configuration Key for switching
between automatic /
manual operation
LED indicators for
limit contactor relays
(switching state)
LED indicator for alarm
function
Display of active
contact and key for
relay switching in
manual mode
Field for user labelling
Fig. 4.1
Operating elements of
Liquisys M
Indication of current operating mode: “auto”(green LED) or “manual”(yellow LED)
Indication for relay controlled in “manual”mode (red LED)
Indicates the state of relays 1 and 2.
LED green: measured value is within permissible limits, relay is inactive.
LED red: measured value is outside permissible limits, relay is active.
Alarm indication for continuous limit violation, temperature sensor failure or system errors
(see error list in chapter 7).
05
Setpoint
pH
R262
DISPL-3E.CDR
Measuring mode
indicator (normal
operation)
Calibration mode
indicator
Setup mode
indicator
(configuration)
In measuring mode:
secondary measured value.
In setup / calibr. mode:
e.g. parameter setting
Automatic
temperature
compensation
display
Electrode symbol
(flashes during
ongoing calibration)
Error indicator
In measuring mode:
main measurement value.
In setup / calibr. mode:
e.g. parameter
‘Hold’mode
indicator (outputs
reflect last current
status)
Rel 3/4 state indicators
active inactive
Function coding display
In measuring mode:
quantity measured.
In setup mode:
parameter adjusted
Fig. 4.2 Liquid crystal display
PM253E04.CHP
Liquisys M CPM 223 / 253 Operation
Endress+Hauser 17

4.3 Key functions
CAL key
When the CAL key is pressed, the instrument
prompts for the calibration access code (fixed
setting: 22 for calibration or any other number
to view the calibration data). Acknowledge
with the CAL key to proceed. Use the CAL
key to continue through the calibration
process.
Note:
The calibration data set in function
group C are used for calibration.
ENTER key
The ENTER key has several functions:
- It calls up the setup menus from the
measuring mode
- It is used to store (acknowledge) data
entered in setup mode
- It is used to start calibration (same
function as CAL key)
PLUS key
MINUS key
The PLUS and MINUS keys have the following
functions:
- They are used to select function groups;
to set parameters and numeric values
(the setting speed increases when the
key is held down); and
- to operate the relays in manual mode
(see chapter 4.2).
- In the measuring mode, the PLUS key
switches to °F and disables the
temperature display (see chapter 4.7),
while
- the MINUS key selects the error display
(see chapter 4.7).
REL key
The REL key is used in manual mode to
switch between the relays and the manual
start cleaning function.
AUTO key
This key is used to toggle between the
automatic and manual modes of operation.
Escape function
Press the PLUS and MINUS keys
simultaneously to return to the main menu,
in calibration mode: at the end of calibration.
Press the PLUS and MINUS keys again to
return to the measuring mode.
Locking the hardware
Access to field operation can be locked for
communication via HART or PROFIBUS.
Press the PLUS key and the ENTER key at the
same time to lock the instrument. The code
prompt displays the code 9999.
Unlocking the hardware
To unlock, press the CAL and MINUS keys at
the same time. The code prompt displays the
code 0.
Operation Liquisys M CPM 223 / 253
18 Endress+Hauser