091236
SE 557
Manual
4.3 Pressurizing the Fitting
During possible sensor sterilization and during nor-
mal operation, it is important that the fitting and
electrolyte pressure is adjusted to be higher than the
effective pressure in the reactor vessel. This reduces
the risk of process fluid getting into the sensor.
The optimal pressure difference value to keep the
junctions clean and obtain acceptable electrolyte
refill intervals has to be established empirically from
case to case, however it should be at least 0.5 bar.
5 Maintenance and Cleaning
Regularly check the applied fitting overpressure
during operation, and re-adjust if required. Regularly
check the electrolyte level in the sensor. When reach-
ing the end of the bulbous shaft section (reservoir),
refill with electrolyte up to the indication line for max.
level. Carefully rinse the sensor tip and junction with
pure water after each operating cycle. Under no cir-
cumstances 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
(ZU 0958). If a sensor is stored dry for a few days by
mistake, let it soak in electrolyte for several hours be-
fore use.
6 Accessories
Connecting cable
VP6-ST
3 m
CA/VP6ST-003A
5 m
CA/VP6ST-005A
10 m
CA/VP6ST-010A
20 m
CA/VP6ST-020A
7 Specifications
Model Designation
The model designation, which is printed on each
sensor and on the packaging label, includes the
following information:
SE 557X /1-NMSN Model designation (example)
Sensor material
(see pH glass table)
N: Alpha glass
H: Omega glass
Sensor connector
VP: VP (VarioPin)
MS: MS (Memosens®)
Solution ground
N: Without
Length
1: 120 mm
2: 250 mm
4: 450 mm
Ex approval
X: Yes
Further Data
pH range
0 ... 14
Pressure, relative
-1 ... 6 bar
Junction
Ceramic (2x)
Electrolyte
ZU 0958
Reference system
Ag/AgCl
Mounting
PG 13.5
Temp detector
VP connector: Pt1000
MS connector: NTC 30 kΩ
pH Glass (Sensor Material)
Model Code Designation Process
temperature
Features
N:
Alpha glass
-20 ... 100 °C (Medium imped-
ance, universal
glass, fluoride
resistant)
H:
Omega glass 0 ... 135 °C
(High impedance
for high-tem-
perature appli-
cations, very low
alkali error, CIP/SIP
capable)
8 Disposal
Observe the applicable local or national regulations
for disposal.
Instructions for Use for the SE 557 pH Sensors
!
WARNING – Failure to observe this warn-
ing may result in serious injury.
The warning symbol on the rating plate
means:
Read these instructions for use, observe the
Specifications, 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 atmosphere 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 the corresponding local requirements
and standards for electrical installations in
hazardous areas. 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.
1.3 Hazardous Areas – Sensors with Memosens
Connector
Memosens Ex sensors are marked by an
orange-red ring. The Memosens Ex sensors
shall only be connected to a cable of type
CA/MS-***X** or type CA/MS-***X**-L or to an
intrinsically safe and certified Memosens mea-
suring cable which is identical in hardware and
function.
1.4 Hazardous Areas – Sensors with VP
Connector
The sensors shall only be operated with an
approved device in floating, intrinsically safe
circuits. The electrical input ratings of the
sensors shall not be exceeded.
2 Intended Use
Together with a suitable fitting, the sensor is used for
continuous measurement of pH values in liquid me-
dia. The SE 557 is a high-precision sensor with liquid
electrolyte. It has an integrated temperature detector
for automatic temperature compensation. The sensor
is sterilizable.
3 Installation and Commissioning
1. On unpacking, check the sensor for mechanical
damage. Report any damage to your Knick ser-
vice team.
2. Remove the watering cap and briefly rinse the
sensor with clean water. After rinsing, the sen-
sor should only be dabbed dry with a tissue. Do
not rub the pH-sensitive glass, since this can lead
to electrostatic charging and sluggish response
times.
3. Check the space behind the pH-sensitive glass for
the presence of any air bubbles and remove them
by gently swinging the sensor in a vertical plane.
4. Open the electrolyte filling hole before insert-
ing the sensor into the fitting. Suitable fittings
for operating this sensor type can be found at
www.knick-international.com.
5. Install the sensor in the grounded fitting as
described in the user manual of the respective
fitting.
6. Connect sensor and cable.
4 Operation
4.1 Calibrating the Sensor
2-point calibration is recommended for the SE 557
sensor. First remove the watering cap. Then dip the
sensor successively into two different buffer solutions
with given pH values (e.g., pH 7.00 and pH 4.00) and
calibrate the pH transmitter to these buffer values.
Please refer to the user manual of the pH transmitter
for further details.
4.2 Sterilizing
For application in sterile processes, such as fermenta-
tion, sterilize the sensor before starting the operating
cycle. This sensor type allows the whole fermenter/
reactor unit including pH sensor to be sterilized.
1
Ø 12 mm
5
3
Knick
Elektronische Messgeräte
GmbH & Co. KG
Beuckestraße 22
14163 Berlin
Germany
Phone: +49 30 80191-0
Fax: +49 30 80191-200
Email: [email protected]
TA-SE557-KNE04 201600518
1
Sensor connector:
a: VP,
b: Memosens®
2
Serial number
3
Filling hole
4
Maximum filling height
5
Rating plate
e
.g
. 120 / 250 / 450
mm
Ø 32 mm
Ø 32 mm
120
/
250
/
450
mm
Position electrode
this side up
max. level
D-14163
Berlin
BVS 09
AT
EX E 088
X
II 1G Ex ia IIC
T3/T4/T6
0044
SE 557X/*-NMS
H
pH 0 to 14
,-1 to 6 ba
r,
0 to 135 °C
2
a
b
Position el ec trode
this side up
max. level
TÜ
V
15
AT
EX
164143
M
ade
in
Ge
rm
an
y
0044
II 1
G
Ex
ia
IIC
T3
/T
4/
T6
14163
Be
rlin
SE
55
7X
/1
-N
VP
N
p
-1
to
6
ba
r
C°
00
1
ot
02
-
p
me
T
0
to
14
pH
re
l
4
