Memmert WNB 7 User manual

Waterbath
WNB 7 - 45
OPERATING INSTRUCTIONS

BASIC
page 2

BASIC
page 3
1 General notes and
safety notes
safety notes
You have purchased a technically fully proven product which has been produced in Germany with the
use of high-grade materials and the application of the latest manufacturing techniques; it has been
factory tested for many hours.
For this waterbath we guarantee spare parts to be available up to 10 years.
Observation of the Operating Instructions is necessary for faultless
Observation of the Operating Instructions is necessary for faultless
operation and for any possible claims under warranty. If these
operation and for any possible claims under warranty. If these
Instructions are disregarded, all claims under warranty, guarantee
Instructions are disregarded, all claims under warranty, guarantee
and indemnifi cation are excluded!
This mark on the product means:
Note Operating Instructions
Note Operating Instructions
Warning – bath hot when operating
Warning – bath hot when operating
The right to technical modifi cations is reserved.
Dimensional details are not binding.
1.1
Transport
Transport
Always use gloves!
If the units WNB 22 to 45 have to be carried, 2 persons are required.
Place the bath accurately horizontal and
Place the bath accurately horizontal and
not on an infl ammable support!
not on an infl ammable support!

BASIC
page 4
2
Technical data
Model
7
10
14
22
29
45
Volume [liter]
7
10
14
22
29
45
Usable bath length A [mm]
240
350
350
350
590
590
Usable bath width B [mm]
210
210
290
290
350
350
Usable bath depth C [mm]
140
140
140
220
140
220
Housing length D [mm]
468
578
578
578
818
818
Housing width E [mm]
356
356
436
436
516
516
Housing height (with fl at cover) F [mm]
238
238
238
296
238
296
Housing height (with gable cover) G [mm]
337
337
347
405
343
401
Weight [kg]
11
14
16
17
24
26
Current consume [A]
5,2
5,2
7,8
8,7
10,4
12,2
Power [W]
1200
1200
1800
2000
2400
2800
Ambient conditions
Ambient temperature 5ºC - 40°C
rh max. 80% (no condensation)
Overvoltage Category: II
Contamination degree: 2
Setting temperature range
10°C to 95°C
with activation of the
boiling mode up to 100°C, see
section 4.3.1
Setting accuracy
0,1°C
Indication accuracy
0,1°C
Working temperature range
5ºC above ambient temperature to
nominal temperature
= maximum temperature (see rating plate)

BASIC
page 5
2.1
Material quality
Material quality
Memmert is using stainless steel (
Mat.Ref. 1.4301) for the external casing as well as for the interior, an
outstanding material because of its high stability, optimum hygienic features and corrosion resistance
against many (not all!)
chemical combinations (Attention e.g. at chlorine combinations!).
The load has to be tested for its chemical compatibility with the materials mentioned above.
A material-compatibility table covering all these materials can be requested from MEMMERT.
WARNING! Always pull out the supply plug before
WARNING! Always pull out the supply plug before
opening the bath cover!
opening the bath cover!
2.2
Electrical equipment
Electrical equipment
•
Operating voltage see rating label, 50/60 Hz
•
Protection Class 1, i.e. operating isolation with ground connection to EN 61 010
•
Protection IP20 to DIN EN 60 529
•
Interference suppression to EN55011 Class B
•
Bath protected by a fuse 250V/15A fast blow
•
Controller protected by a 80 mA fuse (200 mA on 115 V)
•
When connecting a MEMMERT bath to the electrical supply you have to observe any local
regulations which apply (e.g. in Germany DIN VDE 0100 with FI protection circuit)
2.3 Note on EMC (
2.3 Note on EMC (
electromagnetic compatibility)
electromagnetic compatibility)
This product is intended to operate on a supply network with a system impedance Z
max
at the transfer
point (building connection) of 0.292 Ohm max. The user has to ensure that the product is only operated
on an electrical supply network which meets these requirements. If necessary, details of the system
impedance can be obtained from the local electricity supply authority.
Note:
Any work which involves opening up the bath must only be
Any work which involves opening up the bath must only be
carried out by a properly qualifi ed electrician!
carried out by a properly qualifi ed electrician!
2.4
Brief technical description
Brief technical description
MEMMERT-waterbaths are electrically heated and electronically controlled.
The temperature of the thermostating liquid is continuously controlled by a microprocessor-controller
with pulse package control. Electronic microprocessor-PID-controller with continuous power matching
and
autodiagnostic system with fault indicator (see section 12), integral timer for digital programme
time selection.
The temperature is
measured using a
Pt 100 temperature sensor (4-wire circuit). The accuracy is as
follows:
WNB
Setting accuracy
0,1ºC
Temperature fl uctuation
±0,1ºC
The components of temperature control are controlled by integrated malfunction-recognition. The
heaters are installed outside - therefore no problems through dirt or limeresidue.

BASIC
page 6
2.5
Standard equipment
Standard equipment
•
Electronic fuzzy-supported PID process controller with delayed programme start and
programmable hold time. The controller has permanent power matchinig and an
autodiagnostic system for rapid fault fi nding
•
Recessing push/turn control for simple operation of bath
•
Visual alarm indication
•
Mechanical temperature limiter (TB Class 1)
•
Monitor relay to switch off heating in case of fault
•
High-grade stainless-steel Pt100-temperature sensor (Mat.Ref. 1.4571) Class A in 4-wire circuit
•
Boiling mode for temperatures above 95°C
Special equipment (to be ordered separately as accessory): fl at cover with concentric ring sets, gable
cover to drain condensate, cooling device, various racks for test tubes, bottles etc
3
Installation
The unit must be placed on a
horizontal, non-flammable surface
which cannot tilt.
The vent openings in the left and back side
must
remain unobstructed. Minimum wall spacing on all
sides is 80 mm. The minimum spacing from the top of the bath to the next ceiling (rack, etc.) is 750 mm.
3.1
Initial start-up
Initial start-up
When the bath is started up for the fi rst time, it should be supervised continuously until steady conditions
have been reached.
3.2
Start-up - waterbath
Start-up - waterbath
Mains
connection The mains connection cable must be placed away from any hot surface.
space for
air circula-
tion
space for
air circula-
tion
min.
750mm
min.
80mm
min.
80mm

BASIC
page 7
Operation with non-fl ammable thermostating liquids only!
Operation with non-fl ammable thermostating liquids only!
drain valve
max water level
min water level
Note
•
The tray may suffer damage as a result of corrosion and pitting, causing the temperature control
fl uid to infi ltrate the heating system. Only ever use demineralised water with a conductance level of
5-10 microsiemens and a pH value between 5 and 7.
•
The tray may suffer damage if ultrapure water or DI water with an electrical conductance level
of below 5 microsiemens is used. Only ever use pretreated water with a conductance level of 5-10
microsiemens.
•
When fi lling the bath, make sure you stop when the
liquid level is between the two fi ll level
marks on the right inside wall of the tray. Water baths may have a
water level control feature (see
section 9).

BASIC
page 8
4
Bath construction and operation
Bath construction and operation
The
heating positioned on three sides around the tank ensures a natural
water circulation of the liquid
inside, thus securing an optimal
uniform temperature distribution.
4.1
Controls and
indications
relatively largest heat loss (since fur-
thest away from the heated ribs)
minimum heat loss (since
very close to the heated ribs)
bath
Insulation
heating elements
time-symbol
delay-symbol
(delayed switch-on)
hold-symbol
(hold time)
alarm-symbol
SET key
temperature display
heater-symbol
push/turn control
7 5. 0

BASIC
page 9
4.2
Switching on
Switching on
The bath is switched on by pressing the push/turn control
and can be operated in connection with
the SET-key.
Bath switched off: The push/turn control is
pushed in and protected against damage.
4.3 Setting the
4.3 Setting the
parameters
parameters
A parameter can be selected by rotating the push/turn control; all other parameters are then dimmed.
The selected parameter fl ashes brightly and can now be altered with the push/turn control while holding
down the SET key (protection against unintentional alteration).
If the push/turn control is rotated quickly the setpoint is altered in large steps; with slow operation it is
altered in single steps.
After the SET key has been released the newly set value is stored.
Further rotation of the push/turn control selects the next parameter.
Rotation of the push/turn control selects the following parameters (in the order indicated), to be altered
as described above:
1.
Temperature setpoint
2.
Delayed switch-on
3.
Hold time of the setpoint temperature

BASIC
page 10
4.3.1 Temperature setpoint
4.3.1 Temperature setpoint
The bath starts to heat up
immediately to the set temperature.
Adjustment range:
Adjustment range:
10
°C to
95
°C or ca.
100
°C with
activation of the boiling mode
Setting and indication accuracy:
Setting and indication accuracy:
0,1
°C
Rotate the push/turn control until the
°C
symbol fl ashes.
The
setpoint temperature can then be selected with the SET key depressed,
as described in section 4.3. After releasing the SET key the display briefl y
fl ashes the setpoint. The display then changes to the actual temperature and
the controller starts to control to the selected setpoint temperature.
During heating the
symbol fl ashes in proportion to the actual heater power.
In order to reach water temperatures above 95°C (boiling point), waterbaths
are provided with the boiling mode. If this is selected, the heating is switched
on permanently.
Activating the
boiling mode by rotating the push/turn control beyond the
maximum value until the display shows “
CCC
“
The setting “boiling mode“ is not stored permanently. After the bath is switched
off and on again, the controller shows again the previously selected setpoint.
°C
°C
4.3.2
Delayed switch-on
Delayed switch-on
The bath starts to heat up to the previously
selected temperature only after the time of
the switch-on delay has elapsed.
Adjustment range:
Adjustment range:
1
min bis
99.59
hrs
Setting accuracy:
Setting accuracy:
1
min
Indication accuracy:
Indication accuracy:
<10 hrs:
1
min
≥10 hrs:
1
hr
Rotate the push/turn control until the
(delay) and the
symbol fl ashes.
The duration of the delayed switch-on can then be set with the SET key
depressed as described in section 4.3. After the SET key has been released
the bath briefl y fl ashes the setting of the switch-on delay.
The delayed switch-on is then activated and the display alternates between
the actual temperature and the running time of the switch-on delay. The time
is shown with a negative sign and runs down. In this way it is possible to
determine at any time how much longer the bath waits until it begins to heat
up.
If no delayed switch-on is required, it can be de-activated by the setting “
OFF
“.
°C
°C
°C
ϑ
t
90°C
ϑ
t
delay 12h
90°C