Instruction Manual for Heating Cables and Cold Leads Type 68994- and 68997- Catalogue no. 68994- and 68997- Hemstedt GmbH Schleicherweg 19 D-74336 Brackenheim-Botenheim Phone +49 (7135) 9898-0 Fax +49 (7135) 2197 e-mail: info@hemstedt.de WEB: www.hemstedt.de 02-2010 1
Document: A5 68990-0-005 Date: 18.02.2010 Revision: 2 2 02-2010
Description The single core series resistance Heating Cables and Cold Leads Type 68997- / 68994- from electrical resistance trace heatingwhich is used to raise or maintain the temperature of a workpiece where it is externally applied. The series resistance Heating Cables and Cold Leads Type 68997- / 68994- can be used in the Hemstedt Trace Heating System HEM-SYS-SER-1 with the Splice Type HEM-CON- or similar splices which are suitable for the application, conductor and cable sizes. Ratings Withstand temperature: -60 C through +260 C Rated voltage: 450/750 V Impact strength: Typ 68997- : 7 Joule Typ 68994- : 4 Joule For further data see tables on page 4 and 5 02-2010 3
Type 68997-... Catalogue no.: Electrical resistance at +20 C r Ω/m Conductor cross section mm 2 Outer diameter mm mm Temperature coefficient of resistance 20... 105 C 10 A Capacity between conductor and braid c pf/m Minimum bending radius mm 68997-0,00108 68997-0,00171 68997-0,0029 68997-0,004 68997-0,0044 68997-0,0072 68997-0,01 68997-0,0117 68997-0,0 68997-0,0178 68997-0,025 68997-0,03 68997-0,05 68997-0,05 68997-0,065 68997-0,08 68997-0,1 68997-0,1 68997-0, 68997-0,18 68997-0,2 68997-0,32 68997-0,36 68997-0,38 68997-0,48 68997-0,6 68997-0,65 68997-0,7 68997-0,81 68997-1 68997-1,44 68997-1,75 68997-1,75 68997-2 68997-3 68997-8 0,00108 0,00171 0,0029 0,004 0,0044 0,0072 0,01 0,0117 0,0 0,0178 0,025 0,03 0,05 0,05 0,065 0,08 0,1 0,1 0, 0,18 0,2 0,32 0,36 0,38 0,48 0,6 0,65 0,7 0,81 1 1,44 1,75 1,75 2 3 8 16,14 10,24 5,93 4,45 3,95 2,45 1,81 1,47 1,16 1,00 0,98 1,54 0,98 1,06 0,75 0,61 1,48 0,49 0,98 0,56 0,73 0,92 0,41 0,77 0,62 0,49 0,46 0,42 0,59 0,48 0,33 0,28 0,28 0,51 0,34 0,13 10,2 8,6 7,6 6,6 6,7 5,5 5,6 5,2 5,0 4,9 4,9 5,2 4,9 4,9 4,7 4,6 5,2 4,5 4,9 4,6 4,7 4,8 4,4 4,7 4,6 4,5 4,5 4,4 4,6 4,5 4,3 4,3 4,3 4,5 4,7 4,1 +3000 +350 bis +450 +350 bis +450 +500 bis +900 +350 bis +450 +180 +350 bis +450 +300 bis +400 +300 bis +400 +50 bis +0 25 25 4 02-2010
Type 68994-... Catalogue no.: Electrical resistance at +20 C r Ω/m Conductor cross section mm 2 Outer diameter mm mm Temperature coefficient of resistance 20... 105 C 10 A Capacity between conductor and braid c pf/m Minimum bending radius mm 68997-0,0072 68997-0,01 68997-0,0117 68997-0,0 68997-0,0178 68997-0,025 68997-0,03 68997-0,05 68997-0,05 68997-0,065 68997-0,08 68997-0,1 68997-0,1 68997-0, 68997-0,18 68997-0,2 68997-0,32 68997-0,36 68997-0,38 68997-0,48 68997-0,6 68997-0,65 68997-0,7 68997-0,81 68997-1 68997-1,44 68997-1,75 68997-1,75 68997-2 68997-3 68997-8 0,0072 0,01 0,0117 0,0 0,0178 0,025 0,03 0,05 0,05 0,065 0,08 0,1 0,1 0, 0,18 0,2 0,32 0,36 0,38 0,48 0,6 0,65 0,7 0,81 1 1,44 1,75 1,75 2 3 8 2,45 1,81 1,47 1,16 1,00 0,98 1,54 0,98 1,06 0,75 0,61 1,48 0,49 0,98 0,56 0,73 0,92 0,41 0,77 0,62 0,49 0,46 0,42 0,59 0,48 0,33 0,28 0,28 0,51 0,34 0,13 4,94 4,75 4,60 4,42 4,30 4,27 4,59 4,27 4,33 4,11 4,01 4,56 3,90 4,27 3,96 4,10 4,23 3,82 4,13 4,01 3,90 3,87 3,83 3,99 3,89 3,74 3,70 3,67 3,92 3,75 3,47 +3000 +350 bis +450 +350 bis +450 +500 bis +900 +350 bis +450 +180 +350 bis +450 +300 bis +400 +300 bis +400 +50 bis +0 02-2010 5
Certification The series resistance Heating Cables and Cold Leads Type 68997 / 68994- are certified for use explosive atmospheres as components according to the following standards: - EN 60079-0 : 2006 - IEC 60079-0 : 2004 - EN 60079-30-1: 2007 - IEC 60079-30-1: 2007 - EN 61241-0 : 2006 - IEC 61241-0 : 2004 - EN 61241-1 : 2004 - IEC 61241-1 : 2004 This fact is recorded in the EC Type Examination Certificate KEMA 09ATEX0021 U and IECEx Certificate of Conformity IECEx KEM 10.0010 U. The maximum sheath temperatures of the electrical resistance trace heating system Type HEM-SYS-SER-1 comprising of Heating Cables and Cold Leads Type 68997- / 68994- have not been verified. For application in ATEX Categories 2G and 2D as well as Zones 20 and 21 the maximum sheath temperatures have to be established by a Notified Body. Two methods are available: 1. By controlled design according to EN-IEC 60079-30-1 clause 4.4.3 a) 2. By systems approach, design verification method according to EN-IEC 60079-30-1 clause 5.1.13.2 For electrical safety the Heating Cables and Cold Leads are assessed according to the following standard: EN 62395-1 : 2006 6 02-2010
Marking of Heating Cables and Cold Leads Type 68997- und 68994- Hemstedt D-74336 Type 6899I*II*-III* Ω/m 750 V 0344 II2GD Ex e II Ex td A21 KEMA 09ATEX0021 U IECEx KEM 10.0010 U -60 C T serv +260 C <<serial number**>> see instructions A5 68990-0-000 lllll m *: See table below **: Year of manufacturing is coded in the serial number as follows: Manufacturing number directly followed by a two digit number for the year for example 08 lllll: 5 digit marking of length in m Warnings For installation in potential explosive atmospheres, national legislation has to be considered as well as the international standards EN-IEC 60079-14 and EN-IEC 60079-30-2. De energize all applicable power circuits before installation, servicing and maintenance. Ensure that all line conductors are isolated from the power supply this includes the neutral conductor. Keep ends of Heating Cables, Cold Leads and kit components such as the connectors dry before and during installation. Caution, for the series resistance Heating Cables and Cold Leads of Type 68994- or similar cables with reduced levels of mechanical strength (4 J impact energy or 800 N deformation force): Only use in areas with low risk of mechanical damage. 02-2010 7
Circuit protection requirements for branch circuits A means of isolating all line conductors from the supply. Each branch circuit shall be provided with over current protection like adequate fuses or breakers. A means of protecting against earth faults which depend on the type of system earthing (see IEC 60364-5-55 for definitions). For TT- and TN-systems using earth-fault protective devices: The trace heating branch circuit protection shall be capable of interrupting high-impedance earth faults as well as short circuit faults. This shall be accomplished by an earth-fault interruption capability for use in conjunction with suitable circuit protection. The preferred trip level for adjustable devices is 30 ma above any inherent capacitive leakage characteristics of the heater as specified by the persons involved in the design and planning of the electric trace heating systems. This instruction manual contains values of the capacity between conductor and braid (c). It is possible to calculate the capacitive leakage current depending on the length of the Heating Cable or Cold Lead. Neglecting the capacity of the Cold Lead: Xc = - 1 / (2 * π * f * C), C = length of Heating Cable * capacity per unit of length => l * c f = frequency of the supply voltage Where condition of maintenance and supervision ensure that only qualified persons will service the installed systems, and continued circuit operation is necessary for the safe operation of the equipment or processes, earth fault detection without interruption is acceptable if alarmed in a manner to ensure an acknowledged response. For IT-systems: An electrical insulation monitoring device shall be installed to disconnect the supply whenever the electrical resistance is not greater than 50 Ω/V of rated voltage. 8 02-2010
Personnel Aspects Persons involved in the installation of the Heating Cables and Cold Leads shall be suitably trained in all special techniques required. Installation shall be carried out under the supervision of a qualified electrician who has undergone supplementary training in electric trace heating systems for use in potential explosive atmospheres. The instruction manuals, which have been made available by the supplier, have to be carefully followed up. System Design The connector for the Heating Cables and Cold Leads Type HEM-CON-S is developed as a component of a trace heating system according to EN 60079-30-1. The complete trace heating system has to be designed by appropriately by qualified personnel, the design engineer. The systems design is not included in the scope of supply of the Hemstedt trace heating system HEM-SYS-SER-1, the connector Type HEM-CON-S nor the Heating Cables and Cold Leads Type 68997- / 68994-. For the installation, the result of the systems design, the design data such as design drawings and bills of material have to be added to this instruction manual. Storage Check the reels visually for possible damage which might have occurred during transportation and dirt. The Heating Cables and Cold Leads are to be stored in a clean and dry environment. Make sure that the marking on the cables always match the marking on the reels on which they are stored. Unwinding the Heating Cables or Cold Leads A stable and secured support shall be used for the reel when unwinding the cable. When selecting the appropriate support consider size and weight of the reel. 02-2010 9
When unwinding the cable consider following issues: - Only pull straight from the front of the reel; - Avoid too much tensile force; - Avoid folding or twisting and compression of the cable; - Do not pull the Heating Cables or Cold Leads over sharp edges; - Do not step on the cables or use them as loop line; - Do not cross the cable with vehicles. Necessary Tools and Materials Tools: 1. Wirestripper with blade *: Manufacturer: Weitkowitz Catalogue no: 90818 or equivalent 2. Cablecutter *: Manufacturer: Weitkowitz, Type: KS 35 Catalogue no: 90842 3. Sidecutter for fine metallic braid *: Manufacturer: Knipex Type: round head, with bevel and lead catcher Catalogue no: 77 12 1 Remark: * These parts are included in the special Hemstedt tool box: Supplier: Hemstedt Type: HEM-CON-TK-1 Catalogue no: 68990-1-200 10 02-2010
Consumable Materials: 1. Connector for Heating Cables and Cold Leads: Supplier: Hemstedt Type: HEM-CON-S Catalogue no: 68990-1-100 Or equivalent 2. Caution labels electrical trace heating: Supplier: Hemstedt Catalogue no: 68990-0-002 Fixing materials: Fixing materials shall be suitable for the temperature of use and other applicable environmental conditions. For example: For fixing materials, like adhesive tapes, which are applied on stainless steel workpieces or the connector for Heating Cables and Cold Leads Type HEM-CON-S the Chlorite content is to be considered. The use of metal fixing materials or other means of fixing which could harm the construction of the Heating Cables or Cold Leads are not permitted. Fixing materials are not included in the scope of supply of Hemstedt. 02-2010 11
Installation of Heating Cables and Cold Leads of Type 68997- und 68994- General: Heating Cables and Cold Leads shall be installed on clean and smooth parts of the workpieces. Special care shall be taken at flanges, valves and other fittings to orient trace heaters in such a manner as to avoid damage from sharp or jagged surfaces, as well as damage due to impact, abrasion or vibration. The Heating Cables and Cold Leads shall not be bended with a radius smaller than the minimum bending radii specifi ed in this instruction manual. Notice that the minimum bending radii can differ between types and resistance values of the Heating Cables and Cold Leads (see tables on pages 4 and 5). Heating Cables shall not be folded. The Heating cables should be installed to provide as intimate a contact as is reasonably possible to the surface to be heated. Where such contact is not possible, such as on valves, a suitable heat-conductive covering of temperature rated metal foil or other heat-conducting materials may be used. In order to avoid hotspots in the tracing system attention shall be paid to avoid the Heating Cable to be folded, twisted, or to be overlapped, or cross or touch itself. Single core series resistance Heating Cables are often installed as loops tracing the workpiece, especially in these cases attention shall be paid to these requirements. Connection and termination of Heating Cables and Cold Leads: For the connection of the Cold Leads to power supply circuits, suitably certified for the application and correctly installed cable glands, junction boxes and other connection material shall be applied. The glands shall be chosen and mounted in a way that they ensure a level of ingress protection of IP 66 according to EN-IEC 60529. 12 02-2010
The metal braid of the trace heating system must be connected to a suitable earthing terminal. For connecting the Cold Leads to the Heating cables or for the extension of the Heating Cables the connector of type HEM-CON-S- shall be used. The connectors are supplied by pair. The instruction manual enclosed with the connectors shall be considered. The metallic braid is to be terminated to the connector in the way as described in those instruction manuals. In the installation of trace heating systems, only genuine components may be used. Otherwise the system certification will not apply. Fixing and banding: For straight runs fixing materials should be located at intervals not exceeding 300 mm, and for spiral tracing runs, not exceeding 2 000 mm. Additional fixings should be applied at bends, flanges and other obstructions. Warning or marking labels (Catalogue no. 68990-0-002) shall be affixed to the cladding of the thermal insulation of the traced workpiece in consistent intervals along the trace heating circuit. These labels shall also be placed on the cladding over each valve or other piece of equipment that may require periodic maintenance. 02-2010 13
Commissioning of the trace heating As well as after installation of the trace heating as after installation of the thermal insulation and cladding following tests have to be performed and recorded in a test report. These test results have to be provided with Reclamations from the field. Example: Test report a) Electrical insulation resistance test: The resistance of the electrical insulation shall be measured between the conductor and the metallic braid of the Heating Cables and Cold Leads by means of a test voltage of minimal 500 Vdc but recommended 2 500 Vdc. The measured insulation resistance shall not be lower than 20 MΩ. b) Check of electric safety devices: - The installation of all components of the branch or trace heating circuit has to comply with the applicable safety requirements. - Circuit protection requirements for branch circuits are to be checked, see the applicable chapter further above in this instruction manual. c) Verification of design data: The design data, as laid down during the design of the branch or trace heating circuit in the design documentation, shall be verified several minutes after the circuits are energized. Verification can be done by measuring parameters like supply voltage, current and pipe temperature with appropriate measures and equipment. 14 02-2010
Maintenance Fault location: Specialized methods of fault location are necessary to find faults in electric trace heating systems covered by thermal insulation and metallic cladding, and advice should be sought from the electric trace heating system designer. Often faults are caused by mechanical damage, corrosion, overheating or ingress of moisture. The test report established at commissioning shall be consulted and all tests, checks and verifications should be repeated as a basic actions for fault location. Repairs: Repair of Heating Cables and Cold Leads of Type 68997- und 68994- has to be carried out in accordance with this instruction manual. Per judgment on site, shorter pieces of Heating Cables and Cold leads can be replaced completely. For longer cables: Remove the thermal insulation for about 1 m to both sides of the allocated fault of the Heating Cables and Cold Leads. Any dirt has to be removed for 0,5 m on both sides of the allocated fault, than remove the faulty part of the cable by cutting the cable at 0,3 m distance on both sides of the fault. A new piece of Heating Cable or Cold Lead being about 1 m longer than the removed faulty piece shall be fixed to the workpiece at the appropriate place. The new cable shall be of exactly the same type and resistance value as the removed faulty piece. For connecting the new piece to the remainder of the trace heating circuit the connector of type HEM-CON-S (catalogue no. 68990-1-100)* shall be used. The connectors are supplied by pair. The instruction manual enclossed with the connectors shall be considered. * For the necessary tools and consumable materials the special Hemstedt tool box (Catalogue no. 68990-1-200) shall be used. 02-2010
Hemstedt GmbH Schleicherweg 19 D-74336 Brackenheim-Botenheim Phone +49 (7135) 9898-0 Fax +49 (7135) 2197 e-mail: info@hemstedt.de WEB: www.hemstedt.de 16 02-2010