BUCHI K-436 User Manual

Operation Manual

SpeedDigester

K 425/K 436

11593346 en

Table of contents

Table of contents

1	About this manual . . . . . . . . . . . . . . . . . . . . . . . .		. . .	. . . . . .	. . .	. .	. 5
2	Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. . .	. . . . . .	. . .	. .	. 6
	2.1	User qualification . . . . . . . . . . . . . .	. .	. . . .	. .	. .	6
	2.2	Proper use . . . . . . . . . . . . . . . .	. .	. . . .	. .	. .	6
	2.3	Improper use . . . . . . . . . . . . . . . .	. .	. . . .	. .	.	6
	2.4	Safety warnings and safety signs used in this manual . .	. .	. . . .	. .	. .	7
	2.5	Product safety					9
	2.5.1	General hazards					9
	2.5.2	Warning labels on housing and assemblies . . . . . .	. .	. . . .	. .	.	10
	2.5.3	Personal protective equipment . . . . . . . . . .	. .	. . . .	. .	.	11
	2.5.4	Built-in safety elements and measures . . . . . . .	. .	. . . .	. .	.	11
	2.6	General safety rules . . . . . . . . . . . . . .	. .	. . . .	. .	.	12
3	Technical data . . . . . . . . . . . . . . . . . . . . . . . . . .		. . .	. . . . . .	. . .	. .	13
	3.1	Scope of application and delivery . . . . . . . . .	. .	. . . .	. .	.	13
	3.1.1	Available system configurations . . . . . . . . . .	. .	. . . .	. .	.	13

3.1.2Accessories for 300 ml sample tubes (for standard applications) . . . . . . . . 14

3.1.3Accessories for 500 ml sample tubes (for large sample volumes / at low nitrogen level) 15

	3.1.4	Accessories for 3rd party production, 250 ml sample tubes . . . . . . . . .		. 15
	3.2	Technical data		16
	3.2.1	SpeedDigester K-425 / 110 – 120 V version . . . . . . . . . . . . . .	.	16
	3.2.2	SpeedDigester K-425 / 220 – 240 V version . . . . . . . . . . . . . .	.	17
	3.2.3	SpeedDigester K-436 / 220 – 240 V version . . . . . . . . . . . . . .	.	18
	3.3	Materials used		19
4	Description of function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		.	20
	4.1	Functional principle . . . . . . . . . . . . . . . . . . . . . .	.	20
5	Putting into operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		.	21
	5.1	Installation site		21
	5.2	System fixation . . . . . . . . . . . . . . . . . . . . . . . .		22
	5.3	Electrical connections		23
6	Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		.	24

6.1Operating controls and housing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

6.1.1	SpeedDigester K-425	— front side . . . . . . . . . . . .	. . . .	.	. 24
6.1.2	SpeedDigester K-425	— rear side			25
6.1.3	SpeedDigester K-436	— front side . . . . . . . . . . . .	. . . .	.	. 26
6.1.4	SpeedDigester K-436	— rear side			27
6.2	Preparing of SpeedDigester, suction module(s) and sample tubes				27
6.2.1	Kjeldahl digestion —preparing sample tubes				28
6.2.2	Peroxide digestion —preparing sample tubes . . . . . . . . .		. . . .	.	29
6.2.3	Installing a suction module and sample tubes (300 ml)				29
6.2.4	Installing 500 ml sample tubes				32
6.2.5	Starting up the SpeedDigester . . . . . . . . . . . . . .		. . . .	.	34
6.3	Performing a Kjeldahl digestion process				34
6.3.1	Preparational steps . . . . . . . . . . . . . . . . . .		. . . .	.	34

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Table of contents

	6.3.2 Starting a digestion process			34
	6.4	Performing a peroxide digestion process . . . . . . . . . . . . . .	.	. 35
	6.4.1	Preparational steps . . . . . . . . . . . . . . . . . . . . . .	.	35
	6.4.2 Starting a digestion process			35
	6.5	Finishing a digestion process . . . . . . . . . . . . . . . . . .	.	. 37
	6.6	Optional 'Stand with drip tray'		40
7	Maintenance and repairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. .	41
	7.1	Customer service . . . . . . . . . . . . . . . . . . . . . .	.	. 42
	7.2	General condition and cleaning instructions . . . . . . . . . . . . . .	.	42
	7.2.1	Breakage of glassware inside a housing chamber		43
	7.2.2	Liquid ingress into the instrument . . . . . . . . . . . . . . . . .	.	43
	7.3	Glass component conditions . . . . . . . . . . . . . . . . . .	.	. 44
	7.3.1	Sample tubes . . . . . . . . . . . . . . . . . . . . . . . .	.	44
	7.4	Sealing system . . . . . . . . . . . . . . . . . . . . . . .	.	44
	7.5	Rack system . . . . . . . . . . . . . . . . . . . . . . . .	.	45
	7.5.1	300 ml sample tube support spring . . . . . . . . . . . . . . . .	.	. 45
	7.5.2	500 ml sample tube support spring . . . . . . . . . . . . . . . .	.	. 46
8	Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. .	47
	8.1	Malfunctions and their remedy		47
	8.2	Device fuses		48
9	Shutdown, storage, transport and disposal . . . . . . . . . . . . . . . . . . . . . .		. .	49
	9.1	Storage and transport		49
	9.2	Disposal		50
	9.2.1	Thermostat(s) . . . . . . . . . . . . . . . . . . . . . . . .	.	50
10	Spare parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. .	52
	10.1	Spare parts, optional accessories and consumables . . . . . . . . . .	.	. 52

11 Declarations and requirements . . . . . . . . . . . . . . .			. .	. . . . . .	. . .	. . .	. .	55
11.1	FCC requirements (for USA and Canada) . . . .	.	.	. . . .	. .	. .	.	. 55
11.2	Declaration of conformity . . . . . . . . . .		. .	. . . .	. .	. .	.	56

4	K-425 / K-436 Operation Manual, Version A

1  About this manual

1 About this manual

This manual describes the SpeedDigester K-425 / K-436 and provides all information required for its safe operation and to maintain it in good working order.

It is addressed to laboratory personnel and operators in particular.

Read this manual carefully before installing and running your system and note the safety precautions in chapter 2 in particular. Store the manual in the immediate vicinity of the instrument, so that it can be consulted at any time.

No technical modifications may be made to the instrument without the prior written agreement of Buchi. Unauthorized modifications may affect the system safety or result in accidents. Technical data are subject to change without notice.

Note

The symbols pertaining to safety (WARNINGS and ATTENTIONS) are explained in chapter 2.

This manual is copyright. Information from it may not be reproduced, distributed or used for competitive purposes, nor made available to third parties. The manufacture of any component with the aid of this manual without prior written agreement is also prohibited.

The English manual is the original language version and serves as basis for all translations into other languages. If you need another language version of this manual, you can download available versions at www.buchi.com.

5	K-425 / K-436 Operation Manual, Version A

2  Safety

2 Safety

This chapter introduces the safety concept of the instrument and contains general rules of behavior and warnings from direct and indirect hazards concerning the use of the product.

For the users safety, all safety instructions and safety messages in the individual chapters shall be strictly observed and followed. Therefore, the manual must always be available to all persons performing any tasks described herein.

2..1 User qualification

The instrument may only be used by laboratory personnel and other persons who on account of training and professional experience know the potential dangers that can develop when operating the instrument.

Untrained personnel, or persons who are currently being trained, require careful supervision by a qualified person. This Operation Manual serves as a basis for training.

2..2 Proper use

The SpeedDigester K-425 / K-436 has been designed and built for laboratory use only. Its intended use is to allow digestion of samples with concentrated acids or peroxides by heating up the probe.

A suction unit (e.g. Scrubber or water jet pump) has to be connected to the suction module to safely withdraw fumes which will emerge during digestion. In any case, all exhausts and fumes leaving the system or assemblies such as Scrubber or water jet pump have to be removed instantly inside a fume hood. This is mandatory to remove all possibly hazardous substances (e.g. acid fumes) from the working area. The ventilation system of the fume hood has to be equipped with safety measures such as outlet filters to avoid contamination of the environment.

When the SpeedDigester K-425 / K-436 is used in combination with other instruments (e.g. Scrubber and fume hood) all related manuals are to be fully observed.

2..3 Improper use

Applications not mentioned in section 2.2 are considered to be improper. Applications which do not comply with the technical data (see section 3 of this manual) are also considered to be improper.

The operator bears the sole risk for any damages or hazards caused by improper use!

The following uses are expressly forbidden:

•Digestion operations outside an active fume hood.

•Digestion of samples (e.g. food and feed) in nitrosulfuric acids which can produce explosive nitro compounds.

•Digestion of sample material of unknown composition in nitrosulfuric acids.

•Use of samples which can explode or ignite due to shocks, friction, heat or sparks.

•Installation or use of the instrument in rooms, which require ex-protected instruments.

•Use of glassware which is not specified in section 2.5.4.

6	K-425 / K-436 Operation Manual, Version A

2  Safety

2..4 Safety warnings and safety signs used in this manual

DANGER, WARNING, CAUTION and NOTICE are standardized signal words for identifying levels of hazard seriousness of risks related to personal injury and property damage. All signal words, which are related to personal injury are accompanied by the general safety sign.

For your safety it is important to read and fully understand the table below with the different signal words and their definitions!

	Sign	Signal word	Definition	Risk level
		DANGER	Indicates a hazardous situation which, if not avoided, will result in
			death or serious injury.
		WARNING	Indicates a hazardous situation which, if not avoided, could result
			in death or serious injury.
		CAUTION	Indicates a hazardous situation which, if not avoided, may result
			in minor or moderate injury.
	no	NOTICE	Indicates possible property damage, but no
			practices related to personal injury.	(property damage only)

Supplementary safety information symbols may be placed in a rectangular panel on the left to the signal word and the supplementary text (see below example).

	Space for	!	SIGNAL WORD
		Supplementary text, describing the kind and level of hazard / risk seriousness.
	supplementary
	safety	• List of measures to avoid the herein described, hazard or hazardous situation.
	information	• ...
	symbols.	• ...

Table of supplementary safety information symbols

The reference list below incorporates all safety information symbols used in this manual and their meaning.

Symbol Meaning

General warning

Electrical hazard

Heavy weight, avoid overexertion

Explosive gases, explosive environment

7	K-425 / K-436 Operation Manual, Version A

2  Safety

Symbol Meaning

Explosive material

Fire hazard

Harmful to life-forms

Hot item, hot surface

Device damage

Inhalation of substances

Chemical burns by corrosives

Fragile components

Wear laboratory coat

Wear protective goggles

Wear protective gloves

Heavy weight, lifting requires more than one person

8	K-425 / K-436 Operation Manual, Version A

2  Safety

Additional user information

Paragraphs starting with Note transport helpful information for working with the device / software or its supplementaries. Notes are not related to any kind of hazard or damage (see following example).

Note

Useful tips for the easy operation of the instrument / software.

2..5 Product safety

The SpeedDigester K-425 / K-436 has been designed and built in accordance with current state-of- the-art technology. Safety warnings in this manual (as described in section 2.4) serve to make the user alert to and avoid hazardous situations emanating from residual dangers by giving appropriate counter measures.

However, risks to users, property and the environment can arise when the instrument is damaged, used carelessly or improperly.

2..5..1 General hazards

The following safety messages show hazards of general kind which may occur when handling the instrument. The user shall observe all listed counter measures in order to achieve and maintain the lowest possible level of hazard.

Additional warning messages can be found whenever actions and situations described in this manual are related to situational hazards.

!DANGER

Death or serious injuries by use in explosive environments.

•Do not store or operate the instrument in explosive environments

•Do not store chemicals in the vicinity of the device

•Operate the device in a fume hood with sufficient ventilation to directly withdraw fumes

!WARNING

Death or serious burns by flammable vapors.

•Remove all sources of flammable vapors

•Do not store flammable chemicals in the vicinity of the device

9	K-425 / K-436 Operation Manual, Version A

2  Safety

!WARNING

Risk of death or serious chemical burns by hot acid or peroxide fumes.

•Do not operate the system with faulty parts

•Check instrument setup for proper sealing before use

•Do not inhale process fumes

•Operate the instrument inside an active fume hood

• Do not move the instrument or parts of it during digestion

!CAUTION

Risk of minor or moderate cuts by sharp edges.

•Do not touch defective or broken glassware with bare hands

•Do not touch thin metal edges

!CAUTION

Risk of burns by hot machine parts and glassware.

•Do not touch hot parts or surfaces

•Let the system and inserted glassware cool down safely

•Do not move the instrument or parts of it when hot

NOTICE

Risk of instrument damage by liquids or mechanical shocks.

•Do not spill liquids over the instrument or its components

•Do not move the instrument when it is loaded with sample liquid

•Do not drop the instrument or its components

•Keep external vibrations away from the instrument

•Safely attach the instrument to the bench in earthquake prone regions

•Do not operate the instrument without the protection cover installed at the front

2..5..2 Warning labels on housing and assemblies

The following warning sticker(s) can be found on the housing or assemblies of the SpeedDigester:

Symbol	Meaning	Location
	Hot item, hot surface	Sticker / label, located on top of the housing and
		at the racks

Do NOT put rack into side cooling position

Label on 500 ml racks

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2  Safety

2..5..3 Personal protective equipment

Always wear personal protective equipment such as protective eye goggles, protective clothing and gloves. The personal protective equipment must meet all requirements of the supplementary data sheets for the chemicals used.

!WARNING

Serious chemical burns by corrosives.

•Observe supplementary data sheets of all used chemicals.

•Handle corrosives in well ventilated environments only.

•Always wear protective goggles.

•Always wear protective gloves.

•Always wear protective clothes.

•Do not use damaged glassware.

2..5..4 Built-in safety elements and measures

Buchi glassware design

•All original Buchi digestion glassparts are made of high temperature and chemical resistant borosilicate glass.

•Acid fumes generated during digestion accumulate in the suction module

•The fumes must be safely withdrawn from the suction module via one or more hoses to a Scrubber (e.g. Scrubber B-414) or via water jet pump into a sink or sufficient suction flow.

3rd party glassware

The quality of the material is an essential part of the safety concept of the SpeedDigester K-425 / K-436. For the special rack (order no. 11055440), the following qualified vendors offer sample tubes of sufficient quality grade to withstand the temperatures and the aggressive chemical digestion agents:

	Qualified vendor			Tested sample tube(s)
	Gerhardt			250 ml / 6100
	Velp			ø 42×300 mm / A00000144
	Foss			250 ml / 10014278

Heater

Each heating chamber is equipped with a safety overtemperature switch. In case of an emergency the switch cuts off the power of the corresponding chamber and the 'Heating indicator' light.

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2  Safety

2..6 General safety rules

Responsibility of the operator

The head of the laboratory is responsible for training his/her personnel.

The operator shall inform the manufacturer without delay of any safety-related incidents which might occur during operation of the instrument or its accessories. Legal regulations, such as local, state and federal laws applying to the instrument or its accessories must be strictly followed.

Duty of maintenance and care

The operator is responsible for the proper condition of instrument. This includes maintenance, service and repair jobs that are performed and on schedule by authorized personnel only.

Spare parts to be used

Use only genuine consumables and spare parts for maintenance to assure good system performance, reliability and safety. Any modifications of spare parts or assemblies are only allowed with the prior written permission of the manufacturer.

Modifications

Modifications to the instrument are only permitted after prior consultation and with the written approval of the manufacturer. Modifications and upgrades shall only be carried out by an authorized Buchi technical engineer. The manufacturer will decline any claim resulting from unauthorized modifications.

12	K-425 / K-436 Operation Manual, Version A

3  Technical data

3 Technical data

This chapter introduces the reader to the SpeedDigester K-425 / K-436 and its specifications. It contains the scope of delivery, technical data, requirements and performance data.

3..1 Scope of application and delivery

All system configurations come with a limited set of accessories as a starter kit. Within a system family, additionally available accessories (see section 3.1.2 and the following) can be used to easily reconfigure your system to every configuration listed in section 3.1.1.

Parts that are required to change a system configuration:

•Rack

•Suction module

•Insulation plate (fireclay insert)

•Sample tubes

The scope of delivery depends on the ordered system configuration and can be checked according to the individual delivery note and the listed order numbers.

Note

For additional information about the listed products, see www.buchi.com or contact your local dealer.

3..1..1 Available system configurations

SpeedDigester K- 425

Configuration

Sample

Sample tube sizes

Suction modules

order number

positions

Condensate

Module for

110 – 120 V

220 – 240 V

5

6

250 ml

300 ml

500 ml

Standard

H2O2

3rd party

trap

tubes

1154251500

1154252500

•

•

•

1154251100

1154252100

•

•

•

1154251200

1154252200

•

•

•

1154251300

1154252300

•

•

•

1154251400

1154252400

•

•*

•*

*Third party sample tubes require special accessories such as the BUCHI “Module for 3rd party tubes” and the matching rack / insulation plate. Tubes are not included in the set!

Note

The SpeedDigester K-425 is available in different versions for 110 – 120 V or 220 – 240 V mains supply. Check your local voltage requirements and order accordingly!

13	K-425 / K-436 Operation Manual, Version A

3  Technical data

SpeedDigester K- 436

Configuration

Sample

Sample tube sizes

Suction modules

order number

positions

Condensate

Module for

110 – 120 V

220 – 240 V

10

12

250 ml

300 ml

500 ml

Standard

H O

3rd party

trap

2

2

tubes

n.a.

1154362500

•

•

•

n.a.

1154362100

•

•

•

n.a.

1154362200

•

•

•

n.a.

1154362300

•

•

•

n.a.

1154362400

•

•*

•*

*Third party sample tubes require special accessories such as the BUCHI “Module for 3rd party tubes” and the matching rack / insulation plate. Tubes are not included in the set!

Note

The SpeedDigester K-436 is only available for 220 – 240 Vmains supply. Check if a voltage converter is necessary to adapt your local mains level before connecting the instrument!

3..1..2 Accessories for 300 ml sample tubes (for standard applications)

	Item	Additional info	Order number	Recommended quantity
					to order
				K-425		K-436
	Set of sample tubes	300 ml, 4 tubes	037377	2×		3×
	Suction module standard	6 place	11055849	1×		2×
	Suction module condensate trap	6 place	11055865	1×		2×
	Suction module H2O2	6 place, cpl.	11055853	1×		2×
	Connectors to suction module	Adapter and plug	11055367	1×		2×
	EPDM hose	Set for K-425	11056005	1×		—
	EPDM hose set	Set for K-436	11056219	—		1×
	Insulation plate (fireclay)	Insertion, for 300 ml tubes	11055142	1×		2×
	Rack	6 place, for 300 ml tubes	11055248	1×		2×
	Glass caps (set of 4)	OPTIONAL	040049	—		—
	Insulation cap	OPTIONAL	11056024	—		—
	Sealing FKM (set of 6)	Spare part	038122	—		—
	Sealing PTFE (1 pcs)	OPTIONAL	022442	—		—
	Rubber GUKOs for H2O2 suc. mod.	Spare part set of 6	044495	—		—
	Filter funnel for H2O2 suc. mod.	Spare part set of 6	044494
	Set circular spring and holder	Spare part set of 6	11055984	—		—
	Bed-plate for 300ml racks	OPTIONAL	11055943	—		—

14	K-425 / K-436 Operation Manual, Version A

3  Technical data

3..1..3 Accessories for 500 ml sample tubes (for large sample volumes / at low nitrogen level)

Standard items	Additional info	Order number	Recommended quantity
				to order
			K-425		K-436
Sample tubes	500 ml, single tube	026128	5×		10×
Set of sample tubes	500 ml, 4 tubes	043982	2×		3×
Suction module condensate trap	5 place	11055851	1×		2×
Connectors to suction module	Adapter and plug	11055367	1×		2×
EPDM hose	Set for K-425	11056005	1×		—
EPDM hose set	Set for K-436	11056219	—		1×
Insulation plate (fireclay)	Insertion, for 500 ml tubes	11055143	1×		2×
Rack	5 place, for 500 ml tubes	11055327	1×		2×
Base for rack	For 500 ml tubes rack	11055612	1×		1×
Glass caps (set of 4)	OPTIONAL	040049	—		—
Insulation cap	OPTIONAL	11056024	—		—
Sealing FKM (set of 6)	Spare part	038122	—		—
Sealing PTFE (1 pcs)	OPTIONAL	022442	—		—
Interlock spring for 500 ml rack	Spare part	11055385	—		—

3..1..4 Accessories for 3rd party production, 250 ml sample tubes

Item	Additional info	Order number	Recommended quantity
				to order
			K-425		K-436
3rd party sample tubes	250 ml	n.a.	6×		12×
Suction module for 3rd party tubes	6 place	11055850	1×		2×
Connectors to suction module	Adapter and plug	11055367	1×		2×
EPDM hose	Set for K-425	11056005	1×		—
EPDM hose set	Set for K-436	11056219	—		1×
Insulation plate (fireclay)	Insertion, for 250 ml tubes	11055877	1×		2×
Rack	6 place, for 250 ml tubes	11055440	1×		2×
Sealing FKM (set of 6)	Spare part	038125	—		—
Set circular spring and holder 6×	Spare part	11055985	—		—

Note

3rd party sample tubes are not available at Buchi. Please contact your local OEM vendor for these type of tubes.

15	K-425 / K-436 Operation Manual, Version A

3  Technical data

3..2	Technical data
3..2..1	SpeedDigester K-425 / 110 – 120 V version
		Technical data
		Power consumption		max. 1280 W
		Temperature control range		level 1 to 10 (70 – 580°C typically)
		Connection voltage		110 – 120 VAC
		Input fuse		T 10A L 250 V
		Frequency		50 / 60 Hz
		IP degree of protection (two digits)		IP 20
				Explanation of protection level:
				2  Protection provided by the enclosure against access
				to hazardous parts (e.g., electrical conductors,
				moving parts) and the ingress of solid foreign objects
				with a diameter of > 12,5 mm.
				0  No protection of the equipment inside the enclosure
				against harmful ingress of water.
		Insulation category		II
		Environmental conditions:
			Pollution degree	2  (for indoor use only)
			Temperature	5 – 40 °C
			Altitude (above sea level)	up to 2000 m
			Humidity (curve parameter)	Maximum relative humidity 80% up to 31 °C, then
				decreasing linearly to 50% relative humidity at 40 °C
		Dimensions in mm (W × D × H)		310 × 620 × 540
		Net weight		12 kg
		Rack (without glassware)		2,5 kg

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3  Technical data

3..2..2	SpeedDigester K-425 / 220 – 240 V version
		Technical data
		Power consumption		max. 1280 W
		Temperature control range		level 1 to 10 (70 – 580°C typically)
		Connection voltage		220 – 240 VAC
		Input fuse		T 10A L 250 V
		Frequency		50 / 60 Hz
		IP degree of protection (two digits)		IP 20
				Explanation of protection level:
				2  Protection provided by the enclosure against access
				to hazardous parts (e.g., electrical conductors,
				moving parts) and the ingress of solid foreign objects
				with a diameter of > 12,5 mm.
				0  No protection of the equipment inside the enclosure
				against harmful ingress of water.
		Insulation category		II
		Environmental conditions:
			Pollution degree	2  (for indoor use only)
			Temperature	5 – 40 °C
			Altitude (above sea level)	up to 2000 m
			Humidity (curve parameter)	Maximum relative humidity 80% up to 31 °C, then
				decreasing linearly to 50% relative humidity at 40 °C
		Dimensions in mm (W × D × H)		310 × 620 × 540
		Net weight		12 kg
		Rack (without glassware)		2,5 kg

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3  Technical data

3..2..3	SpeedDigester K-436 / 220 – 240 V version
		Technical data
		Power consumption		max. 2550 W
		Temperature control range		level 1 to 10 (70 – 580°C typically)
		Connection voltage		220 – 240 VAC
		Input fuse		T 10A L 250 V
		Frequency		50 / 60 Hz
		IP degree of protection (two digits)		IP 20
				Explanation of protection level:
				2  Protection provided by the enclosure against access
				to hazardous parts (e.g., electrical conductors,
				moving parts) and the ingress of solid foreign objects
				with a diameter of > 12,5 mm.
				0  No protection of the equipment inside the enclosure
				against harmful ingress of water.
		Insulation category		II
		Environmental conditions:
			Pollution degree	2  (for indoor use only)
			Temperature	5 – 40 °C
			Altitude (above sea level)	up to 2000 m
			Humidity (curve parameter)	Maximum relative humidity 80% up to 31 °C, then
				decreasing linearly to 50% relative humidity at 40 °C
		Dimensions in mm (W × D × H)		310 × 620 × 540
		Net weight		15,5 kg
		Rack (without glassware)		2× 2,5 kg

18	K-425 / K-436 Operation Manual, Version A