EHT HEAT TRACING SPECIFICATION

EHT HEAT TRACING SPECIFICATION

1.0) CODES AND STANDARDS

1.1) The Electric Heating System must be designed, manufactured, installed and tested in accordance with the latest version of the following codes and standards;

1. National Electrical Code (NEC/NFPA 70)
2. CENELEC Norms
3. National Fire Protection Association (NFPA)
4. National Electrical Manufacturers Association (NEMA)
5. American National Standards Institute (ANSI)
6. Institute of Electrical and Electronics Engineers (IEEE)
7. International Electrotechnical Commission (IEC)
8. All applicable local standards

1.2) The Electric Heating Cable manufacturer must have ISO 9001 certification.

2.0) ENVIRONMENTAL CONDITIONS

2.1 Minimum Ambient Temperature: -30°C

2.2 Maximum Ambient Temperature: 40°C

2.3 Average Temperature: 15 °C

2.4 Wind: 100 km/h

2.4 Corrosive Environment: No

3.0) ELECTRICAL SITE CLASSIFICATION

Equipment, materials and installation must comply with the electrical and hazard classification (ATEX certificate) required by the site. Site Temperature Ratings must be selected according to the Minimum Auto-Flashing Temperature as specified in NEC Standard Section 500 or EN50014 Standard.

4.0) AVAILABLE POWER SUPPLY

Mains voltage is available as 380VAC, 3 Phase, 4 Wire, 50Hz.

5.0) PROTECTION OF PROCESS TEMPERATURE OR FREEZING PROTECTION:

5.1) The purpose of the heat monitoring system is to provide sufficient heat to the outer surfaces of pipes and equipment containing liquid in case of a decrease in the ambient or temperature and to keep them at the desired temperature.

5.2) Each Heat Monitoring system control panel should be sufficient to operate in the following modes;

A. Automatic Control Mode:

1. When the Selector Switch (HOA) is set to the “AUTO” position, automatic protection should be provided for the relevant pipelines. The electric heater should be energized and de-energized by a Temperature Controller set according to the appropriate temperature.
2. The Temperature Controller should monitor the ambient or pipe temperature detected by an RTD sensor placed outside the control panel or on the relevant pipes. The controller should control the contactor that will activate and deactivate the required power. In frost protection, all heaters should be activated and deactivated simultaneously.

B. Manual Mode:

In manual operation, the Heat Tracing system is activated by placing the HOA selector switch in the “HAND” position.

5.3) Each heat tracing panel must contain the following equipment;

• Main Circuit Breaker
• Main Contactor (against freezing) or separate contactors for each temperature control circuit
• Power Distribution Circuits, protection with automatic fuse and residual current relay
• Microprocessor based Temperature Controller with RTD sensor(s)
• “HAND-OFF-AUTO” (H-O-A) selector switch
• “ENERGY ON” Signal Lamp (Green)
• “CONTACTOR ENERGY” Signal Lamp (Green)
• “COMMON ALARM” Signal Lamp (Red)
• “Main Supply Loss” protection relay
• “Voltage Loss” Signal Lamp and Relays
• Lamp Test Button
• Alarm Acceptance Button
• Terminal groups
• Thermostat panel type heater for external type panels

5.4) There should be at least 20% spare space in the control panel.

6.0) HEATER CABLE

Heating cables must be approved for use in this project. The contractor company is responsible for selecting the cable to be used for the given application.

6.1) Self-Regulating Heating Cables

The output power of the heating cable should vary according to the changing temperatures along the pipeline due to heat-losing parts such as pipe fittings and support elements. The cable should be suitable for use by cutting to the desired lengths according to the installation situation.

A. Low Temperature - Self-Regulating Heating Cables

1. Self-Regulating Heating Cables should be resistant to 65°C when energized and 80°C when de-energized.
2. The carrying conductors of the heating cable should be; 2 parallel, nickel-plated copper carrying wires with a cross-section of at least 1.23mm2. A semi-conductor PTC polymer with electrical conductivity should be placed between these two parallel conductors. Then, there should be a Polyolefin jacket on this heating element.
3. This jacket will be covered with a tinned copper or nickel-plated metal braid.
4. Optionally, there will be an outer sheath of polyethylene or fluoropolymer on the copper braid to protect against corrosion.

B. Medium Temperature - Self-Regulating Heating Cables

1. Self-Regulating Heating Cables must be resistant to 110°C when energized and 135°C when de-energized.
2. The carrying conductors of the heating cable should be 2 parallel, nickel-plated copper carrying wires with a cross-section of at least 1.3 mm2. A semi-conductor PTC polyomer with electrical conductivity should be placed between these two parallel conductors. Then, there should be a Fluoropolymer insulating jacket on this heating element.
3. This jacket will be covered with a tinned copper or nickel-plated metal braid.
4. Optionally, an outer sheath of polyethylene or fluoropolymer can be placed on the copper braid to protect against corrosion.

C. High temperature - Self-Regulating Heating Cables

1. Self-Regulating Heating Cables should be resistant to 150-215°C when energized and 215°C when de-energized.
2. The carrying conductors of the heating cable should be manufactured from 2 parallel nickel-plated copper carrying wires with a cross-section of at least 1.3 mm2.
3. A semi-conductor PTC polyomer with electrical conductivity should be placed between these two parallel conductors. Then, a Fluoropolymer jacket should be placed over this heating element.
4. This jacket will be covered with a tinned copper or nickel-plated metal braid.
5. Optionally, a fluoropolymer outer sheath can be placed over this copper braid to protect against corrosion.

6.2) Constant Power Heating Cables

Such heating cables should produce a constant power (W/m) per unit length (1m). The nickel chrome heating element should be wound helically on the insulated voltage-carrying conductors and there should be contact points at certain intervals to complete the circuit with the carrier cables.

A. Low Temperature - Constant Power Heating Cables

Heating Cables should be resistant to 100°C when energized and 180°C when de-energized. They can be insulated with silicone rubber or fluoropolymer.

B. Medium Temperature - Constant Power Heating Cables

1. They should be resistant to 150°C at low powers when energized and 200°C when de-energized.
2. They should consist of FEP+ copper or nickel-plated copper braid+FEP insulation layers.

C. High Temperature - Constant Power Heating Cables

1. They should be resistant to 180 oC at low powers when energized and 260 oC when de-energized.
2. They should be insulated with PFA + copper or nickel-plated copper braid+PFA.

7.0) DESIGN AND DRAWINGS

7.1) A safety factor of 30% should be considered when calculating heat loss.

7.2) When calculating heat loss, it should be considered that the heat insulation may allow space for the heating cable.

7.3) When calculating the heating cable length, the following materials on the pipe should be taken into account:

• Flange
• Pumps
• Valves
• Pipe support / hanger elements
• Air vents and drains
• Instruments

7.4) During the transportation or replacement of the above equipment on the pipe, the heating cable should be suspended in the open air and suitable for continuous operation.

7.5) Power Distribution/Control Panel drawings should show the following values ​​for each circuit;

• Circuit Breaker Type
• Breaker Rated Value
• Heater Type and Length
• Voltage and Power
• Operating Current (Ampere)
• Starting Current (Ampere)
• Power per Unit Length (W/meter)
• Total Power for Each Circuit (Watt)

7.6) All Power and Control Panel Drawings shall show all electrical and instrument internal wiring connections. All wires, terminals, devices shall be numbered and labeled.

7.7) Isometric drawings of the electric heating system for each line shall be made using the pipe and tank isometric drawings to be provided. Isometric drawings shall be sufficient to show heaters, power terminal boxes, terminators, RTDs and other supplied materials.

7.8) The following information shall be provided for each heater circuit:

• Line Location
• Pipeline Numbers
• Valves, Pumps, Flanges and Instruments
• Heater Circuit Numbers
• Heat Loss and Heater Output Power
• Electrical Load
• Heater Catalog Numbers
• Heater Termination Points
• Design Parameters
• Insulation Type and Thickness
• Positions of All Components
• Material List of All Components Used

8.0) HEATER CABLE INSTALLATION

8.1) In general, heater cables are installed on pipes as a single line without making spirals. In places where heat loss exceeds the output power of the cable, a second or as many heaters as necessary may be used in parallel. Applications may be made at a ratio of 1.5/1 with approval.

8.2) Self-regulating, Constant Power and flexible series resistance cables are attached to the pipe surface with fiberglass or polyester adhesive tape at maximum 0.35 meter intervals. It is covered with a suitable aluminum tape.

8.3) Heating cables should be installed in a way that it is not necessary to cut the cables when removing and installing devices and equipment on the line.

8.4) RTD sensors are fixed to the pipe surface in a way that they do not directly feel the temperature of the heating cable.

8.5) Heating cables are installed at the lower parts of the pipe to avoid mechanical damage.

8.6) Heating cables are wrapped on the tooth angle of 45° or 90° elbows.

8.7) Heating cables are installed in accordance with the manufacturer's directives and with appropriate connection parts.

9.0) MANUFACTURING OF THE CONTROL PANEL

9.1) The electric heating panel shall be in dimensions appropriate to the need, preferably made of stainless steel or at least 1.2 mm phosphated and cleaned DKP sheet metal with electrostatic powder or oven paint. Panels to be used outdoors shall be at least IP 65 protection class. In small-sized panels, glass fiber reinforced polyester panels can be used with the approval of the administration.

9.2) Panel color will be RAL 7032, Panel materials will be Siemens, Schneider or Klockner Moller brand.

9.3) Power distribution panel 380 Volt, 3-Phase, 4-wire, minimum 100 ampere capacity copper busbar system and 20% spare capacity.

9.4) The main circuit breaker should be a thermal-magnetic type compact switch with extension arm.

9.5) In each heating cable circuit; There should be a thermal magnetic fuse with a rated short circuit current capacity of 10 kA and an earth leakage current relay with a rated value of 30 mA. Auxiliary contact blocks should be installed on the circuit breakers.

9.6) Alarm In each heating cable circuit; The alarm system will be taken from the auxiliary contact blocks to which the fuse and leakage current relays will be installed. It will definitely not be taken from the relay.

9.7) The signal lamps to be used for each circuit will be LED signal lamps, IP65 and XB5 AVM3 series. Internal “Protection LED” 220 V AC power

9.8) The panel interior lighting lamp will be connected to the door micro switch.

9.9) There shall be a grounded socket inside the panel.

9.10) There shall be no signal interference between the RTD signal cable and the 380V/220V power cables.

9.11) All temperature sensors shall be RTD and shall have IP65 protected terminal boxes. RTDs shall be 3-wire, platinum, 100 ohm at 0°C and with stainless steel sheath.

9.12) All junction boxes shall be IP65 protected and suitable for outdoor use.

9.13) Each frost protection panel shall include a main contactor to control all heating cables fed from the panel. There shall be a contactor for each sensor in temperature protection.

9.14) All control panel instruments, electrical equipment and control devices shall be labeled in accordance with the seller's drawings. Explanations shall be determined by the buyer's requests.

9.15) Each control panel must have a name label on the front surface showing the panel number and description and must be written in letters at least 12 mm high.

10.0) HEAT INSULATION

10.1) Recommended rigid insulation types for electric heating are Expanded Perlite or Polyisocyanurate.

10.2) Recommended non-rigid insulation type is Rock Wool.

10.3) Rigid insulation must be of a size that will leave space for heating cables.

10.4) Non-rigid insulation for pipes 2” and below must also be of a size that will leave space for heating cables.

10.5) Non-rigid insulation for pipes 2” and above must not be of a size that will leave space unless it is necessary due to multiple monitoring.

10.6) All heat insulation must be metal jacketed such as aluminum, stainless steel, etc. and must be installed without any gaps. Water must never leak into the insulation.

11.0) GROUNDING

11.1) Each power circuit connection cable must contain a green insulation grounding wire for grounding of heater power connection boxes and heater additional boxes. This grounding wire must be in accordance with the standards and must be connected to the control panel.

11.2) The metal mesh on the self-regulating heater cables must be grounded by connecting it to the grounding terminal inside the connection box.

11.3) All conduit inputs inside the control panel must be connected to the control panel grounding system.

12.0) CABLE AND CONDUIT

12.1) Control cable cross-sections must be min 1.5 mm2 and power cable min 4 mm2.

12.2) Waterproof type flexible spiral pipe must be used where necessary.

12.3) RTD cable must be 90° FR-PVC outer jacketed, 300Volt, multi-wire copper, twisted three-wire and screened instrument cable. The screen shall be in the form of a wrapped aluminum-polyethylene strip in contact with a tinned copper earth wire.

12.4) The electric heating system wiring shall be kept separate from other wiring systems in the field. Cable trays shall be used for power, control and instrument cables.

13.0) INSPECTION & TESTS

13.1) The specified inspections and tests shall be carried out on each control panel and each heating cable.

13.2) The customer's authorized representative has the right to inspect the control panel and electric heating cables in accordance with industrial standards, the manufacturer's standards and the manufacturer's drawings.

13.3) Each control panel shall be energized at the factory and all operating and alarm functions shall be tested.

13.4) Heating Cable Field Tests

A. In the field, all heating cables shall be subjected to a min. 500-2500 VAC Meger test. The following Meger readings shall be taken on each heating cable.

• A Meger test shall be carried out on the heating cable before installation.
• After the cables are laid but before the heat insulation is applied, the heating cables should be tested with a Meger test.
• After the heat insulation is applied, the heating cable should be tested again with a Meger test.

B. All Meger readings should be 80 MOhm or higher. Otherwise, the heating cable should be repaired or replaced. Field Meger tests should be recorded and reported for each cable.