Lauda RA 12 User manual

Operating instructions
Alpha
Immersion Thermostat
A
Heating Thermostats
A 6, A 12, A 24
Cooling Thermostats
RA 8, RA 12, RA 24
Read the instructions prior to performing any task!

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Manufacturer
LAUDA DR. R. WOBSER GMBH & CO. KG
Laudaplatz 1
97922 Lauda-Königshofen
Germany
Telephone: [phone]
Fax: [phone]
E-mail [e-mail]
Internet http://www.lauda.de
Q4WA-E_13-004-EN English
Translation of the original operating instructions
Release 7/2022 M
replaces release 12/2022 L, 09/2020 j, 08/2020i

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Prefixed safety notes
Before operating the equipment please read carefully all the instructions and safety notes. If you
have any questions please phone us!
Follow the instructions on setting up, operation etc. This is the only way to avoid incorrect opera-
tion of the equipment and to ensure full warranty protection.
Transport the equipment with care!
Cooling thermostats may NEVER be overturned nor put upside down!
Equipment and its internal parts can be damaged:
by dropping,
by shock.
Equipment must be operated only by technically qualified personnel!
Never operate the equipment without a proper heat transfer liquid!
Never operate the equipment without sufficient water or heat transfer liquid level!
Do not start up the equipment, if:
it is damaged or leaking,
the supply cable is damaged.
Switch off the equipment and pull out the mains plug for:
servicing or repair,
before moving the equipment!
Drain the bath before moving the equipment!
Have the equipment serviced or repaired by properly qualified personnel only!
The device may only be used in the following areas:
Production, quality assurance, research and development in an industrial environment.
The Operating Instructions include additional safety notes which are identified by a triangle with an exclamation
mark. Carefully read the instructions and follow them accurately! Disregarding the instructions may have serious
consequences, such as damage to the equipment, damage to property or injury to personnel.
Product specifications are subject to change without notice!

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Table of content
Prefixed safety notes ..................................................................................................................................................................... 3
1SAFETY NOTES............................................................................................................................................................................6
1.1 GENERAL SAFETY NOTES ....................................................................................................................................................... 6
1.2 OTHER SAFETY NOTES ...........................................................................................................................................................7
2BRIEF OPERATING INSTRUCTIONS....................................................................................................................................8
3CONTROL AND FUNCTIONAL ELEMENTS .................................................................................................................... 10
4UNIT DESCRIPTION............................................................................................................................................................... 15
4.1 ENVIRONMENTAL CONDITIONS......................................................................................................................................... 15
4.2 TYPES OF UNIT ..................................................................................................................................................................... 15
4.3 BATHS .................................................................................................................................................................................. 15
4.4 PUMP ................................................................................................................................................................................... 15
4.5 MATERIALS........................................................................................................................................................................... 16
4.6 TEMPERATURE INDICATION,CONTROL AND SAFETY CIRCUIT.......................................................................................... 16
4.7 REFRIGERATION SYSTEM .................................................................................................................................................... 16
4.8 STANDARD ACCESSORIES................................................................................................................................................... 16
5UNPACKING............................................................................................................................................................................. 17
6PREPARATIONS ...................................................................................................................................................................... 18
6.1 ASSEMBLY AND SETTING UP............................................................................................................................................... 18
6.2 FILLING AND EMPTYING...................................................................................................................................................... 21
6.3 HEAT TRANSFER LIQUIDS AND HOSES ............................................................................................................................... 22
6.4 CONNECTION OF EXTERNAL CIRCUITS.............................................................................................................................. 24
7STARTING UP ........................................................................................................................................................................... 25
7.1 CONNECTION TO THE SUPPLY ........................................................................................................................................... 25
7.2 SWITCHING ON.................................................................................................................................................................... 25
7.3 GENERAL KEY FUNCTIONS AND PILOT LAMPS................................................................................................................... 26
7.4 TEMPERATURE SETPOINT SETTING SET............................................................................................................................. 27
7.5 AUTOMATIC SHUTDOWN TIMER ASD............................................................................................................................... 27
7.6 DEFINING TEMPERATURE LIMITS HIAND LO................................................................................................................... 28
7.7 REFRIGERATION UNIT SUBMENU COOL............................................................................................................................ 28
7.8 OFFSET FOR THE INTERNAL TEMPERATURE PROBE CAL ................................................................................................ 29
7.9 RESTORING WORKS SETTINGS DEF ................................................................................................................................... 29
7.10 STANDBY STBY................................................................................................................................................................... 30
7.11 SAFETY FUNCTIONS ............................................................................................................................................................ 30
7.11.1 Safety functions and removal.................................................................................................................................... 30
7.11.2 Overtemperature and low level protection.............................................................................................................. 31
7.11.3 Overtemperature and low level protection testing.................................................................................................. 31

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7.11.4 Unlock the overtemperature protection ..................................................................................................................32
7.11.5 Pump-motor supervision: Overload.........................................................................................................................32
7.11.6 Fault list “Alarms and Errors” ....................................................................................................................................33
8MAINTENANCE........................................................................................................................................................................34
8.1 CLEANING............................................................................................................................................................................34
8.2 MAINTENANCE ....................................................................................................................................................................34
8.2.1 Service intervals..........................................................................................................................................................34
8.2.2 Testing the heat transfer liquid ..................................................................................................................................35
8.2.3 Maintenance of the refrigeration unit.......................................................................................................................35
8.3 NOTE ON REPAIR.................................................................................................................................................................35
8.4 DISPOSAL INFORMATION....................................................................................................................................................35
8.4.1 Disposal of refrigerant................................................................................................................................................35
8.4.2 Disposal of packaging.................................................................................................................................................35
8.5 ORDERING SPARES AND RATING LABEL.............................................................................................................................36
9ACCESSORIES..........................................................................................................................................................................37
10 TECHNICAL DATA AND DIAGRAMS.................................................................................................................................39
11 DECLARATION OF CONFORMITY AND PRODUCT RETURNS................................................................................45
12 COPYRIGHT ..............................................................................................................................................................................48
13 INDEX..........................................................................................................................................................................................49
Explanation of symbols
Caution
This sign is used where there may be injury to personnel if a
recommendation is not followed accurately or is disregarded.

Note
Here special attention is drawn to some aspect. May include
reference to danger.

Reference
Refers to other information in different sections.

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1Safety notes
1.1 General safety notes
The units are designed for operation with non-flammable liquids to DIN EN 61010-2-010.
A laboratory thermostat is intended for heating, cooling and pumping liquids according to the needs of the user. This
leads to hazards by high or low temperatures, fire, and the general hazards due to the application of electrical energy.
The user is largely protected through the application of the appropriate standard specifications.
Further hazard sources may arise from the type of material being thermostated, for example by exceeding or undercut-
ting certain temperature thresholds or by the fracture of the container and reaction with the heat transfer liquid.
It is not possible to cover all possibilities; they remain largely within the responsibility and the judgement of the operator.
The unit must only be used as intended and as described in these Operating Instructions. This includes operation by suit-
ably instructed qualified personnel.
The units are not designed for use under medical conditions according to DIN EN 60601-1 or IEC 601-1!
Classification in accordance with EMC requirements
Unit
Immunity requirements
Emissions class
Customer power supply
Heating and cooling
thermostats
Alpha
Table 1 in accordance
with
DIN EN 61326-1
Emissions Class B
in accordance with
CISPR 11
Only for EU
Domestic connection value ≥
100 A
Table 1 in accordance
with
DIN EN 61326-1
Emissions Class B
in accordance with
CISPR 11
Rest of the world (outside EU)
No limitation
Valid for the USA:
Instructions for Class A digital devices
“This equipment has been tested and found to comply with the limits for Class A digital device, pursuant to Part 15 of
the FCC (Federal Communication Commission) Rules. These limits are designed to provide reasonable protection
against harmful interference when the equipment is operated in a commercial environment. This equipment generates,
uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual,
may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to
cause harmful interference in which case the user will be required to correct the interference at his own expense.”
“This device complies with Part 15 of the FCC (Federal Communication Commission) Rules. Operation is subject to
the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any
interference received, including interference that may cause undesired operation.”
Valid for Canada:
“This Class A digital apparatus complies with Canadian ICES-003” (ICES = Interference Causing Equipment Stand-
ards).
«Cet appareil numérique de la classe A est conforme à la norme NMB-003 du Canada».

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1.2 Other safety notes
Check the device carefully for shipping damage before putting into operation. Never start a damaged device!
Only technically qualified personnel must operate the equipment!
Connect the unit only to grounded mains power (PE).
Parts of bath covers (types Alpha RA xx) may reach surface temperatures above 70 °C when operating at higher
temperatures. Take care when touching the device! Danger of burns!
Use suitable hoses (6.3).
Protect tubing with hose clips against slipping off. Avoid kinks in the hoses!
Check hoses from time to time for possible material defects!
Heat transfer hoses and other hot parts must not come into contact with the supply cable!
When using the thermostat as circulation thermostat, failure of hoses may lead to leaking of hot heat transfer liquid
and become a danger to personnel and objects.
When no external consumer is connected to the thermostat the pump outflow must be linked to the return!
The units are designed for operation with non-flammable liquids to DIN EN 61010-2-010 only.
Depending on the heat transfer liquid used and the mode of operation it is possible for irritating vapours to be pro-
duced. Ensure appropriate ventilation!
Always pull out the mains plug before cleaning, maintenance or moving the thermostat!
Repairs on the control unit and/or the refrigeration system must be carried out by properly qualified personnel only.
Values for temperature control and indicating accuracy apply under normal conditions according to DIN 12876.
High-frequency electromagnetic fields may under special conditions lead to unfavourable values. This does not af-
fect the safety!

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2Brief operating instructions
This brief instruction shall give you the possibility to operate the unit quickly. For safe operation of the
unit it is absolutely necessary to read all the instructions and safety notes carefully!
1.
Assemble unit and add items as appropriate (6).
2.
Fill the unit with corresponding heat transfer liquid.
When starting up the unit, the tubular heater (3) has to be covered with liquid! (6.2).
Heating and immersion thermostats:
Fill the bath with decalcified water (6.3).
Cooling thermostats:
Fill the bath with proper glycol/water mixture (6.3).
The units are designed only for operation with non-flammable liquids to DIN EN 61010-2-010.
Take care of the level of the heat transfer liquid! (6.2).
3.
Connect the unit only to a socket with a protective earth (PE) connection.
Compare the information on the rating label with the supply details.
4. 4
.
Switch the unit on with the front switch .
5. 5
.
Now the display shows the current bath temperature, for example
On warning or error message refer section (7.11).

The overtemperature cut-out point SAFE is fixed at 105 °C and cannot be changed.
However, you can adjust a minimum and maximum operation temperature of the thermostat (7.6).
Bath temperature
2%3

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(7.6)
(7.8)
Reset to factory default:
Display: dEF
“Enter” pressed for longer than
3 seconds sets back to default:
SEt = 25 °C; Hi = 105 °C;
Lo = -30 °C; Cool= Auto.
(7.5)
(7.4)
(7.7)
Calibrate probe (offset):
Input temperature of reference
thermometer (only offset values
±5 K of actual bath temperature are
accepted).
Display flashes. Set value
with or . Value is accepted
after 4 seconds or proceed immedi-
ately with the key: .
(7.9)
Flashing display “00.00” (preset)
for inactive timer or “hh.mm” for
time to initiate status “Standby”.
Activate timer by setting the Auto
Shut-Down Delay “hh.mm” with
or .
Deactivate timer by setting
“00.00”.
The setting is accepted only by
pressing the key: .
Bath temperature
2%3
Display flashes. Set Setpoint
with or . Value is accepted
after 4 seconds or proceed immedi-
ately with the key: .
Maximum Temperature
Hi
Minimum Temperature
Lo
Configure Refrig. System
Cool
l
Offset probe
CAL
Settings default
dEF
Timer “Auto Shut Down”
ASd
End of menu
End
Setpoint
SEt
Alarm
nnn
Stand By
StbY
Standard
Alarm
Standby (timer event)
( blinking in timer mode)
Configure Refrigeration System
Default: Auto . Possible settings:
on refrigeration on
Auto refrigeration on if needed
oFF refrigeration off
(3 sec.)

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3Control and functional elements
Alpha immersion thermostat
1 Temperature controller with four segment LED display
2 Heater active (yellow LED is lit)
Cooler active (blue LED is lit)
Error signal (red LED is flashing)
3 Menu functions, select and Enter keys
4 Mains switch
5 Screw clamp
6 Tubular heater
7 Temperature probe Pt100
8 Pump outflow with pump outflow reducer
8
1
2
3
4
5
6
7

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1 Reset button (press only if the display shows SAFE )
2 Cooler cable
3 Rating label
4 Mains cable
5 Screw clamp
1
2
3
4
5

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1 Control head with clamp
2 Bath vessel
3 Four mounting feet
1
2
3

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Alpha Cooling Thermostat
1 Control head
2 Pump connections: return to bath and pump outflow
3 Bath cover
4 Handle on front and back
5 Removable front cover
6 Grille on both sides
7 Four mounting feet
1
2
3
4
5
6
7

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1 Mains cable
2 Rating label
3 Cooler cable
4 Bath drain nozzle
1
2
3
4

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4Unit description
4.1 Environmental conditions
The operation of the thermostats is only allowed under the following conditions as specified in
DIN EN 61010-1 and DIN EN 61010-2-010:
Indoor use, no outdoor installation.
Operation of the device up to an altitude of 2000 m above sea level.
Foundation must be dense, even, non-slippery and non-flammable.
Keep clear distance (6.1).
Ambient temperature range (10).
Use only within this range for an undisturbed operation.
Mains supply voltage fluctuations (10).
Relative humidity (10).
Transient over voltage according to Installation Categories (Over voltage Categories) II.
Pollution degree: 2.
4.2 Types of unit
The type designation of the Alpha thermostats consists of the letter A or RA (R for identification as low-temperature
unit = cooling thermostat).
The immersion thermostat Alpha (control head) and the type of bath or the refrigeration system respectively.
Examples:
RA 8 = Immersion thermostat Alpha (control head) and refrigeration system with bath of 8 liters maximum volume.
A 12 = Control unit Alpha with bath of 12 liters maximum volume.
4.3 Baths
All units -except the immersion thermostat- provide a stainless steel bath. The last two digits of the model no. corre-
spond to the approximate total volume in liter (for example bath RA 24 = approximately 24 liters).
Part of this volume may be used to insert objects. Be precautious to overflow when inserting large volume samples!
For the immersion thermostat the bath volume is limited to 50 liters. The bath has to provide a reliable option to fix the
thermostat clamp (wall thickness 10 –30 mm).
4.4 Pump
All units are equipped with a centrifugal immersion pump. The pumps are driven by a shaded pole motor.
The pump outflow connection can be closed without causing any damage to the pump.
The pump flow can be reduced by the pump outflow reducer.
Pump characteristics (10 Technical data).

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4.5 Materials
All parts being exposed to the heat transfer liquid are made of high quality material appropriate to the operating tem-
perature. Non-rusting stainless steel and high quality temperature-resistant materials are being used.
4.6 Temperature indication, control and safety circuit
The units are equipped with a 4-character LED display, which is used for the display of the measurements and settings,
as well as the operating status. The entry of setpoints and other settings occurs under menu guidance via three keys.
With low level, overtemperature or other alarms the unit switches off the heater on all poles. The pump and the refriger-
ating machine are also switched off. Unlocking the protection system (7.11.2).
A Pt100 temperature probe detects the outflow temperature in the bath. A high-resolution A/D converter processes
the measurement. Further measurement conditioning occurs using a special control algorithm for controlling the heater
actuator and the refrigeration system.
4.7 Refrigeration system
The refrigeration system consists essentially of a hermetically sealed compressor. Heat of condensation and motor heat
are dissipated by a fan-cooled finned condenser. Fresh air is drawn in at the front of the unit; warmed air is discharged at
the back and to the sides. The ventilation openings must not be restricted in order to ensure proper air circulation.
The compressors are fitted with sensors that responds both to the compressor temperature and to the motor current.
Cooling curves (10 Technical data).
4.8 Standard accessories
All refrigerated RA types are delivered with bath covers and an external circulation set to connect an external circuit.
All heating types A 6, A 12 and A 24 are not supplied with bath covers. Cooling coil, bath cover and external circulation
set can be ordered as accessory (9).
A pump outflow reducer avoids to spill over liquid in small baths (A 6, RA 8, A 12, RA 12).

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5Unpacking
After the unit and accessories have been unpacked they have to be examined for potential transport damages. If there is
any damage visible on the unit, a claim must be filled in writing with the freight forwarder (expeditor); a notification to
the freight forwarder (expeditor) is obligatory so that the shipment can be examined. Please also inform the LAUDA
Service (8.5).
Standard accessories:
Catalogue No.
Quantity
Designation
Q4WA-E_13-004-EN
1x
Operating instructions
for all thermostats
UD 425
1x
Screw clamp
for immersion and for heating
thermostats
---
2x
Pump outflow reducer with different hole
sizes (diameter Ø 4.5 or Ø 6.0)
for all thermostats
---
1x
Bath cover
RA (cooling) types only
---
1x
External circulation set
RA (cooling) types only
---
1x
Silicone tube
outlet to inlet (pump connection link)
RA (cooling) types only
EZB 260
Warning label “HOT surface”
for all thermostats

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6Preparations
6.1 Assembly and Setting Up
Do not connect with power mains before assembly and setup is complete!!
Place the unit on a flat surface. If necessary, attach the
appropriate pump outflow reducer R onto the pump
nozzle. In small baths use the pressure reducer to pre-
vent any splashing of heat transfer liquid.
Immersion/Heating thermostats only:
Fix the clamp at the bottom of the control head by two
screws M4 x 6 A3 (1.4541) ISO 7046 (recessed
countersunk flat heads).
Accessory “cooling coil set”:
Fix the cooling coil set at the bottom of the control head
by means of the two screws (pan head with cross recess).
The cooling coil set belongs to the left side of the head.
R

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Hang the thermostat into the bath and fix the clamp
with the knurled screw on the edging of the bath.
The wall thickness has to be 10 –30 mm.
Check for tight fitting!
Carefully attach the immersion thermo-
stat to prevent it dropping into the bath.
If this should occur during operation,
never reach into the bath! Withdraw the
mains plug immediately!

Cooling thermostats only
NEVER overturn the unit and never put it upside down!
After transport and before starting up, store it standing in
upright position for two hours if possible.
Do not cover the ventilation openings.
Keep clear distance of at least 40 cm.
Pump connection link (silicone rubber)
Remove the silicone L-tube at the pump housing to improve the
circulation in the bath (only for operation without external consum-
er).
L-tube (silicone rubber)
Operation with external consumer
(circulation thermostat (6.4))

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When operating as bath thermostat without external consumer the pump outflow connec-
tion has to be linked to the return. At bath temperature above 70 °C the label “HOT sur-
face”supplied must be affixed on the bath at clearly visible position!

The unit can be operated safely up to an ambient temperature of 40 °C.
Depending on the loading of the refrigeration system, a temporary shut-off can occur, especially in
case of an ambient temperature of over 35 °C.
Additionally a higher ambient temperature results in less refrigerating capacity.
When starting up the refrigeration system after a longer time, it can take up to 30 minutes, de-
pending on the ambient temperature and the unit type, until the nominal refrigerating capacity is
reached.