4.4 Temperature Detector
The integrated temperature detector is intended for
automatic compensation of the pH signal and not for
any high-precision and safe temperature indication
or control of the process temperature.
4.5 Sensor Lifetime
Alkaline solutions reduce the sensor lifetime – e.g.,
when the sensor is permanently exposed to 2% sodi-
um hydroxide solution at 80 °C, its lifetime is reduced
to 10–15 hours.
SE 546X/*-NMSN
Manual
Instructions for Use for the SE 546 Series ISFET pH Sensors
1
Memosens® connector
2
Serial number
3
PG 13.5 thread
4
PVDF compression ring
5
EPDM-FDA O-ring (11.5 x 2.6 mm)
6
Nameplate
7
Junction
8
ISFET chip
!
WARNING – Failure to observe this warn-
ing may result in serious injury.
The safety alert symbol on the nameplate
means:
Read these instructions for use, observe the Spec-
ifications, and follow the Safety Instructions.
1 Safety Instructions
1.1 All Applications – All Sensor Variants
Hazards due to pressure, temperature, aggres-
sive media or explosive atmospheres are pos-
sible, depending on the location of use. There-
fore, the installation, operation, and servicing of
the sensor shall only be carried out by suitably
trained personnel authorized by the operating
company.
1.2 Hazardous Areas – All Sensor Variants
Observe all applicable local codes and stan-
dards for the installation of electrical equipment
in hazardous locations. For orientation, please
refer to IEC 60079-14, EU directives 2014/34/EU
and 1999/92/EC (ATEX), NFPA 70 (NEC), ANSI/
ISA-RP12.06.01. The electrical and thermal pa-
rameters of the sensors must be adhered to.
1.3 Hazardous Areas – Sensors with Memosens
Connector
Memosens Ex sensors are marked by an
orange-red ring. Combined with a model
CA/MS-***X** or model CA/MS-***X**-L mea-
suring cable or a certified sensor cable which is
identical in hardware and function, the sensor
may be connected to a suitable measuring
device, as described in the Certificates BVS 15
ATEX E141 X and IECEx BVS 15.0114X.
2 Intended Use
The Knick ISFET pH sensors of the SE 546 series with
Memosens® connector system are break resistant
low-maintenance sensors with integrated tempera-
ture detector for automatic temperature compensa-
tion of the pH signal. The sensors are sterilizable by
autoclaving and are suitable for SIP.
The main areas of application are hygienic and sterile
applications in the food and pharmaceutical industry
and in biotechnology.
3 Installation and Commissioning
•
On unpacking, check the sensor for mechanical
damage. Report any damage to your Knick service
team.
•
Remove the watering cap. Briefly rinse the sensor
with pure water.
•
Install the sensor in the fitting as described in the
user manual of the respective fitting.
•
Make sure that the sensor is properly aligned (di-
rection of flow of the process medium). The ISFET
chip should be placed at an angle of approx. 45°
to the direction of flow. When measuring in media
containing abrasive components, avoid direct flow
to the ISFET chip. The sensor may be mounted up-
side down.
•
Connect sensor and cable.
4 Operation
4.1 Calibrating the Operating Point
When you have connected the sensor to the meter,
first calibrate the operating point in buffer 7.00. See
user manual of the meter.
4.2 Calibrating the Sensor
2-point pH calibration is recommended for the SE 546
sensor. First remove the watering cap. Then dip the
sensor successively into two different buffer solutions
with given pH values (e.g., Knick CaliMat pH 7.00 and
pH 4.00) and calibrate the meter to these buffer val-
ues. Please refer to the user manual of the meter for
further details.
4.3 Sterilizing
For application in sterile processes, such as fermenta-
tion, sterilize the sensor before starting the operating
cycle. Sterilization can be effected in situ by means of
steam or superheated process medium.
120 / 225 mm
1
6
3
7
4
5
Ø 12 mm
2
094772
TA-SE546X_MS-KNX05 20180731
8
bar
°C
-15
0
100
135
10
3
PT diagram
MEMO
SENS
Knick
Elektronische Messgeräte
GmbH & Co. KG
Beuckestraße 22
14163 Berlin
Germany
Phone: +49 30 80191-0
Fax: +49 30 80191-200
Email: [email protected]
7 Disposal
Observe the applicable local or national regulations
for disposal.
5 Maintenance and Cleaning
Carefully rinse the sensor tip and junction with pure
water after each operating cycle. Under no circum-
stances must measuring solution be allowed to dry
on these parts!
When the sensor is not in operation, store it with sen-
sor tip and junction well submerged in electrolyte
(3 mol/l KCl). NEVER let the sensor dry out.
The Memosens connector does not require any main-
tenance. It is resistant against moisture and dirt. For
hygiene reasons, you should nevertheless keep the
connector clean.
6 Specifications
Model Code
The markings on each sensor or on the packaging
label include the following information:
SE 546X/ 1 - NMSN
Model designation
Sensor connector
MS: Memosens®
Solution ground
N: without
Length
1: 120 mm
2: 225 mm
Ex approval
X: Yes
Further Data
pH range
0 ... 14
Process temperature -15 ... 135 °C
Process pressure
See pressure/temperature
diagram
Junction
Ceramic
Reference system
Dual chamber
Sensor material
ISFET ion-sensitive field-effect
transistor
Body material
PEEK, FDA
Installation
PG 13.5
Temp detector
NTC 30 kΩ
0
20
40
60
80
100
120
°C
0
2
4
6
8
10
12
14 pH
Reduced
lifetime
Range of ISFET
application
SE 546X/2-NMSN
14163 Berlin
0044
BVS 15
ATEX E 141 X
Ex ia IIC
T3/T4/T6 Ga
II 1G
