This manual introduces the installation and operation of trace heating circuits using the following
self-regulating trace heaters:
• Danfoss PX Pipe Trace Heating System
The self-regulating trace heater features a temperature-dependent resistive element between two parallel copper conductors, that regulates and limits the heat output of the trace heater according to the
ambient temperature. If the ambient temperature rises, the power output of the trace heater is reduced. This self-regulating property prevents overheating which would cause damage to the trace heater.
Even crossing or overlapping with other trace heaters (or other portions of the same trace heater) are
possible.
The heating system is set up as a fixed equipment heating system for pipes in ordinary areas. Thanks to
the parallel design the trace heater can be cut and installed to any required length as specified in table
on page 7.
Multiple options for connection, splicing and end-termination of the heating circuit are available to
meet the individual requirements on site. A large variety of accessories allows for easy customization
and extensibility.
2 Safety
For safe installation and operation of the Danfoss PX Pipe Trace Heating System, all technical requirements and instructions given in this manual must be followed.
WARNING:
Risk of fire or electrical shock. Follow these guidelines to avoid personal injury or material damage.
• All electrical systems and installations must comply with Danfoss requirements and be installed in
accordance with the relevant electrical codes and any other applicable national and local codes.
• The US and Canadian electrical codes require ground fault protection to be provided for all trace
heating circuits.
• Install the trace heater circuit carefully.
• Use the trace heater in accordance with the intended purpose and strictly comply with the operational data specified in section Technical Data.
• The bending radius of the trace heater must be at least 1” (25 mm). Do not bend on the narrow axis.
• To avoid short circuits, do not connect the trace heater bus wires together.
• Keep all components and the trace heaters dry before and during installation
• Each heating circuit must be marked with electrical warning labels (see section Accessories).
• Keep these instructions for future reference. If applicable, leave them with the end user.
Ambient temperature range-67 °F to +185 °F / -55 °C to +85 °C
Operation temperatures-40 °F to +149 °F /-40 °C to +65 °C
Voltage110 to 120 VAC / 208 to 254 VAC
Heat output3 to 10 W/ft / 10 to 33.6 W/m
ResistanceGrounding braid: < 18.2 Ω/km
Dimensions
polyolefin outer jacket0.46” x 0.23” (11.6 x 5.8 mm)
Minimum bending radius1” (25 mm)
Do not bend in an upright position.
5 Personnel requirements
The personnel executing installation and maintenance tasks must have acquired the skills and specialized knowledge relating to the types of protection and types of devices concerned. At least, the
personnel must have:
• a general understanding of the relevant electrical engineering
• a basic knowledge of quality assurance, including the principles of auditing documentation, traceability of measurements and calibration of measurement instruments.
A heating circuit with self-regulating trace heaters usually consists of:
• Power supply cable connection;
• End-termination.
The following pages list all compatible components for the PX heating system. The respective installation instructions are included in the scope of delivery.
7 Power connection components
The following components can be used for power connection with the PX Pipe Trace Heating System:
Power connection kit
Cable to Junction Box with
½” NPT cable gland
For connection of selfregulating trace heaters in
a junction box. Electrical
insulation is ensured by heat
shrink tubes.
Junction is not included.
Includes end-temination.
Catalog No.: 088L0023
8 End-termination
The following components can be used for end-termination with the PX Pipe Trace Heating System.
End-termination
Connecto NA B-E Silicone end
seal for insulation of the end
of the trace heater.
Includes 5 x endcap and 2 x
Silicone adhesive.
End-termination
Heat shrinkable end cap for
insulation of the end of the
trace heater.
Includes 5 kits.
Before installing any electric trace heating, the person installing must check if the trace heating has
been designed and planned correctly. It is particularly essential to verify the following points:
• complete project planning documentation, operating instructions and installation instructions.
• correct selection of the trace heater and accessories with respect to:
· calculation of heat losses;
· max. permissible operating temperature;
· max. permissible ambient temperature;
· temperature class;
· heating circuit length.
Before installing, make sure that all piping and equipment is properly installed and pressure tested.
Maximum heating circuit length
The following table shows the maximum circuit lengths in m (ft) for the different trace heater types
with standard circuit breaker amperages. Breaker sizing should be based on the National Electrical
Code, Canadian Electrical Code or any other local or applicable code.
NOTICE: If the required trace heater length exceeds the maximum heating circuit length you must
install multiple heating circuits.
The following tools are required for installation of the PX Pipe Trace Heating System:
• Wire cutters
• 2 adjustable wrenches (up to 1” (25 mm)); for installation of an insulation bushing only)
Unrolling the trace heater
WARNING:
Risk of short cuts and/or material damage. Keep the trace heater ends dry before and during installation. Observe the trace heater’s installation instructions.
Danfoss PX Pipe Trace Heating System
1
Unroll the required trace heater in a straight line and cut to the correct length. Cut off the trace
heater ensuring a straight cut.
Do not bend or pinch the trace heater, or pull it over sharp edges.
Installation on pipes
This step is necessary for plastic pipes only since plastic pipes conduct heat less efficiently than
metal pipes do. For metal pipes continue with step 4.
Place aluminium tape where the trace heater will be attached for better heat distribution.
CAUTION: Risk of injury and/or material damage. Never tread on or drive over the trace heater. Do not
use it as a loop for stepping on.
Danfoss PX Pipe Trace Heating System
Preferably install the trace heater in a straight line around the pipe. This saves time, helps to
avoid installation mistakes and prevents damage to the trace heater during the thermal insulation work. Furthermore the trace heater can be easily localised later on.
The trace heater should be installed spirally only if this is expressly specified in the project planning.
NOTICE: When installing allow for an additional length of trace heater for assembling splice connections, tee branches, end seals etc. (approx. 1.6 ft (0.5 m) for each).
Preferably install the trace heater in the lower half of the pipe, but not on the lowest point. This
prevents mechanical damage and allows for better heat distribution.
If you use multiple heating tapes, position them with an offset of 90”.
Always install the trace heater on fittings, valves etc. in such a way, that these are easily accessible and replaceable and heating circuits do not have to be cut up. Therefore, always leave a
sufficiently large trace heater loop.
Through the higher heat losses from fittings, valves, flanges etc a greater length of trace heater is required. This additional requirement is specified in the project planning documents.
The following illustrations show typical types of installation.
NOTICE: The bending radius of the trace heater must be at least 1” (25 mm). Do not bend in an upright
position.
The measurement of the insulation resistance is used to determine damage to the trace heater and
possible installation faults. It must be carried out at the following times:
• Preliminary test (shortly before beginning installation of the trace heater on the construction site);
• Acceptance test (after the complete installation of the heating circuit or fitting of the thermal
insulation);
• Final inspection (immediately after completion of work on the thermal insulation);
• Upon commissioning ;
• Before switching on the installation.
To do the measurement, proceed as follows:
• Use an isolation tester with a minimum testing voltage of 500 VDC and a maximum testing voltage
of 2500 VDC. Recommended testing voltage: 1500 VDC. Required insulation resistance: > 20 MΩ.
• Measure the resistance between each bus wire of the trace heater and the grounding braid.
• Measure the resistance between the grounding braid and the earth potential (for this measurement
the heating circuit must not be grounded yet).
WARNING:
Risk of fire or electrical shock. If the insulation resistance is insufficient you must fix the heating circuit
before putting it into operation.
After completion of the installation work (before fitting the thermal insulation) each heating circuit
must be accepted, if possible in the presence of the client.
All further tests must also be documented in an acceptance test report.
After completion of work on the thermal insulation final inspection and acceptance of the individual heating circuits is recommended. Usually, this is the task of the client or the final customer (final inspection).
Putting into operation
Each heat tracing system can only be put into operation if the following conditions are fulfilled:
• The acceptance test reports for each heating circuit are available and the perfect state of the trace
heating system has been confirmed.
• The thermal insulation has been completely installed and is in a dry condition.
• It has been ensured that the heating circuit is operated in conformance with the technical data
specified by Danfoss.
NOTICE: Upon a cold start, additional heating power is required for heating up tanks and pipes. When
starting the system you should allow sufficient time for heat up.
12 Operation
During operation of the electric trace heating system you must ensure that all components of the
system are operated within the operating data specified by Danfoss.
This applies particularly to observation of the maximum temperature. Operation within these operating data is a precondition for possible later warranty claims.
System documentation
Complete documentation must be carried out for each system, from the project planning stage, through
installation and putting into operation up to periodic maintenance of the trace heating system.
This documentation should include the following:
• Project planning documents;
• Heat loss calculation;
• Selection of the trace heater;
• Piping plans with division of heating circuits;
• Circuit diagrams;
• Up to date piping plans;
• Acceptance reports;
• Reports on repair work and any operations carried out on the tank/pipe system, trace heating
system and thermal insulation;
Check the thermal insulation for possible damage, missing seals, cracks, damage to the outer jacket,
missing thermal insulation bushings for trace heaters and cables, penetrated water or chemicals. If the
thermal insulation is damaged the trace heater should be checked for possible damage.
Damaged trace heaters should be replaced.
Parts subject to wear should be replaced (e.g. seals, locking plates etc).
Check the junction box, connection enclosure and enclosures of temperature regulators for corrosion
and possible mechanical damage. Make sure that all enclosure covers are properly in place.
Check the temperature regulator connecting cables and capillary tube systems for damage and that
their installation is protected against mechanical damage.
Electrical inspection
Measurement of the insulation resistance should be seen as a permanent part of regular maintenance.
For instructions on how to perform the test refer to section Measurement of the insulation resistance
on page 13.
Inspection intervals
For frost protection installations inspections should be carrried out annually before the heating period begins.
For plants designed to maintain process temperatures, inspections should be carried out at regular
intervals, but at least twice a year.
Personnel training courses
Regular maintenance should be carried out by trained, experienced maintenance personnel.
It is recommended that maintenance personnel is supported in learning new developments in application technology and maintenance by regular service.
Repairwork on piping or thermal insulation
Make sure that the plant is isolated for safety before all repairwork.
Take care that the heat tracing system is not damaged during repairwork on the pipes or insulation.
After completion of the repairwork:
• Make sure that the heating circuits are properly installed anew according to the project planning
documentation.
WARNING:
Risk of fire or electrical shock due to damaged components. Remember that self-regulating trace
heaters are designed to be installed only once.
Carry out a visual, functional and electrical test (refer to Section Tests and putting into operation on
page 13).
Connect the trace heater to the power supply (a temporary connection to the construction site power supply is also
possible). The ground fault protection devices and automatic circuit breakers must not be triggered. Each heating cable end
must be warm after approx. 5 to 10 minutes (test by hand).
Use an isolation tester with a minimum testing voltage of 500 VDC and a maximum testing voltage of 2500 VDC. Recommended testing voltage: 1500 VDC. Required insulation resistance: > 20 MΩ. Measure the resistance between each bus wire
of the trace heater and the grounding braid. Measure the resistance between the grounding braid and the earth potential
(for this measurement the heating circuit must not be grounded yet).
Heating Circuit No.
Trace heater lengthft. (m)ft. (m)ft. (m)ft. (m)
Insulation resistance at ________ V > MΩ > MΩ > MΩ > MΩ
This limited product warranty is running for a period of 2 years from the date of purchase. It applies for all Danfoss products
and accessories, that are subject of this manual, against:
• faulty components, and
• faulty manufacturing.
Not covered are any damages caused by:
• accidents,
• improper installation, operation, maintenance or repairs,
• neglect, or
• alteration.
Furthermore Danfoss cannot be hold liable under this warranty for:
• installation or removal costs,
• loss or damage to property,
• loss of revenue or anticipated profits, or
• any other damages or costs directly or indirectly related to the warranty issue.
If all warranty conditions are met, Danfoss will, at its sole discretion:
• repair the concerning product,
• replace the concerning product, or
• refund the purchasing price.
Conditions
The limited product warranty is subject to the following conditions:
• proper installation, operation and maintenance in compliance with the state of the technology and the product
documentation
• presence of completely filled in acceptance reports for all installation, maintenance and repairwork operations
How to claim the warranty
To claim the limited product warranty, you have to:
• Notify Danfoss or your local Danfoss representative by written correspondence or email within 30 days after identification of a possible warranty issue.
• If requested, you must provide any warranty related information to Danfoss, such as:
project planning documents,
acceptance reports for installation, operation, maintenance or repairwork,
etc.
Applicability of implied warranties, state or provincial laws
THE FOREGOING WARRANTY IS IN LIEU OF ALL OTHER REPRESENTATIONS, WARRANTIES, OR CONDITIONS, EXPRESS OR
IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE OR NONIN-FRINGEMENT, AND OF ANY OTHER OBLIGATION OR LIABILITY ON THE PART OF DANFOSS THERMAL
MANAGEMENT, WHETHER BY STATUTE, CONTRACT, STRICT LIABILITY, TORT OR OTHERWISE.
If the goods are a consumer product in Buyer’s jurisdiction, Buyer may have additional legal rights under the applicable national/state/provincial legislation governing the sale of consumer goods. As a result, the above exclusions and/or limitations
on the warranty may or may not apply.
For safe installation and operation of the Danfoss PX Pipe Trace Heating System, all technical requirements and instructions given in this manual must be followed.
WARNING:
Risk of fire or electrical shock. Follow these guidelines to avoid personal injury or material damage.
• All electrical systems and installations must comply with Danfoss requirements and be installed in
accordance with the relevant electrical codes and any other applicable national and local codes.
• The US and Canadian electrical codes require ground fault protection to be provided for all trace
heating circuits.
• Install the trace heater circuit carefully.
• Use the trace heater in accordance with the intended purpose and strictly comply with the operational data specified in section Technical Data.
• The bending radius of the trace heater must be at least 1” (25 mm). Do not bend on the narrow axis.
• To avoid short circuits, do not connect the trace heater bus wires together.
• Keep all components and the trace heaters dry before and during installation
• Each heating circuit must be marked with electrical warning labels (see section Accessories).
• Keep these instructions for future reference. If applicable, leave them with the end user.
• De-energize before installation or servicing.
• Use only original Danfoss accessories.
WARNING:
Risk of short cuts and/or material damage. Keep the trace heater ends dry before and during installation. Observe the trace heater’s installation instructions.
WARNING:
Risk of fire or electrical shock. If the insulation resistance is insufficient you must fix the heating circuit
before putting it into operation.
WARNING:
Risk of fire or electrical shock due to damaged components. Remember that self-regulating trace
heaters are designed to be installed only once.
Afin de garantir la sécurité lors de l’installation et du fonctionnement du système de traçage électrique
Danfoss PX, l’ensemble des exigences techniques et des consignes mentionnées dans le présent manuel doivent impérativement être respectées.
AVERTISSEMENT:
Risque d’incendie ou d’électrocution. Suivez ces consignes pour éviter toute blessure ou dommage
matériel.
• Tous les systèmes et installations électriques doivent satisfaire aux exigences imposées par la société Danfoss et doivent être installés conformément aux normes électriques en vigueur ainsi qu’aux
autres prescriptions nationales et locales applicables.
• Les normes électriques américaines et canadiennes imposent une protection contre les défauts à la
terre pour tous les circuits de traçage électrique.
• La pose du circuit de traçage électrique doit être réalisée avec le plus grand soin.
• Utilisez le câble chauffant conformément à l’usage prévu et en respectant les caractéristiques de
fonctionnement spécifiées à la section Caractéristiques techniques.
• Le rayon de courbure du câble chauffant ne doit pas être inférieur à 1” (25 mm). Ne pas courber le
câble chauffant sur la tranche.
• Pour éviter un court-circuit, ne jamais raccorder ensemble les deux conducteurs du câble chauffant.
• Conservez tous les éléments et les câbles chauffants au sec avant et pendant l’installation.
• Chaque circuit de traçage doit être clairement identifié au moyen d’étiquettes de danger électrique
(cf. section Accessoires).
• Conservez ces instructions pour un usage ultérieur. Le cas échéant, remettez-les à l’utilisateur final.
• Mettre hors tension avant toute installation ou opération de maintenance.
• Utilisez exclusivement des pièces et accessoires d’origine Danfoss.
AVERTISSEMENT:
Risque de court-circuit et/ou de dommages matériels. Conservez les extrémités du câble chauffant
au sec avant et pendant toute la durée de l’installation. Respectez les consignes d’installation des
câbles chauffants.
AVERTISSEMENT:
Risque d’incendie ou d’électrocution. Si la résistance d’isolement est insuffisante, le circuit de
traçage devra être réparé avant d’être mis en service.
AVERTISSEMENT:
Risque d’incendie ou d’électrocution dû à la présence de composants endommagés. N’oubliez pas
que les c âbles chauffants autorégulés sont conçus pour n’être installés qu’une seule fois.
Vous pouvez trouver des instructions en Français ici: lx.danfoss.com
11655 Crossroads Circle
Baltimore, MD 21220 USA
Phone: 1-888-DANFOSS (326-3677)
Fax: 416-352-5981
lx.danfoss.com
Danfoss can accept no responsibility for possible errors in catalogues, brochures and other printed material. Danfoss reserves the right to alter its products without
notice. This also applies to products already on order provided that such alterations can be made without subsequential changes being necessary in specifications
already agreed. All trademarks in this material are property of the respective companies. DEVI and the DEVI logo-type are trademarks of Danfoss A/S. All rights reserved.