Memmert WNB 7 - 45 User Manual

Operating instructiOns

Waterbaths

WNB 7 - 45

1 General notes and safety notes ............................................................................................................3

1.1 Transport .................................................................................................................................3

2 Technical data ..................................................................................................................................... 4

2.1 Material quality .......................................................................................................................5

2.2 Electrical equipment ................................................................................................................5

2.3 Note on EMC (electromagnetic compatibility) ...........................................................................5

2.4 Brief technical description ........................................................................................................5

2.5 Standard equipment ................................................................................................................6

3 Installation ..........................................................................................................................................6

3.1 Initial start-up .......................................................................................................................... 7

3.2 Start-up - waterbath ................................................................................................................7

4 Bath construction and operation ......................................................................................................... 8

4.1 Controls and indications .......................................................................................................... 8

4.2 Switching on ........................................................................................................................... 9

4.3 Setting the parameters ............................................................................................................ 9

4.3.1 Temperature setpoint ..........................................................................................................10

4.3.2 Delayed switch-on .............................................................................................................. 10

4.3.3 Hold time of the setpoint temperature ................................................................................ 11

5 Programming example of a programme sequence ............................................................................. 11

6 Monitoring the programme sequence ...............................................................................................12

7 Temperature monitor and protection devices ..................................................................................... 13

7.1 Mechanical temperature monitor: temperature limiter............................................................13

7.2 Low-level protection .............................................................................................................. 13

7.3 Monitor relay .........................................................................................................................13

8 Use of the cover (special equipment) .................................................................................................14

9 Level control (special equipment) .......................................................................................................14

10 Cooling system (special equipment) ................................................................................................. 15

11 Cleaning and maintenance ..............................................................................................................15

12 Check list for fault rectification ........................................................................................................16

13 Action on supply failure .................................................................................................................. 16

14 Glossary .......................................................................................................................................... 16

15 CE Conformity of Declaration ..........................................................................................................17

16 Address and customer service ..........................................................................................................18

17 Index .............................................................................................................................................. 19

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1 General notes and 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

operation and for any possible claims under warranty. If these

Instructions are disregarded, all claims under warranty, guarantee

and indemnification are excluded!

This mark on the product means:

Note Operating Instructions

Warning – bath hot when operating

The right to technical modifications is reserved.
Dimensional details are not binding.

1.1 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

not on an inflammable support!

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2 Technical data

Model 7 1014222945
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 flat 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)

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2.1 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

opening the bath cover!

2.2 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 ( electromagnetic compatibility)

This product is intended to operate on a supply network with a system impedance Z

at the transfer point

max

(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

carried out by a properly qualified electrician!

2.4 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 fluctuation ±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.

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2.5 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 finding

• 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): flat cover with concentric ring sets, gable cover
to drain condensate, cooling device, various racks for test tubes, bottles etc

3 Installation

min.

750mm

space for

air circula-

tion

min.

80mm

space for

air circula-

tion

min.

80mm

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.

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