Defrost Heating Single Cable

1、 Core testing indicators and operating methods   1.Heating rate detection: Verify whether the heating efficiency meets the standard The heating rate directly reflects the power matching degree and heat transfer efficiency of the heating cable, and needs to be tested in a standard environment. Testing premise Turn off other indoor heat sources (such as air conditioning and heating), keep doors and windows closed, and stabilize the initial room temperature at 18 ℃~22 ℃ (simulating daily use environment); Ensure that the heating cable is powered on normally and the temperature controller is set to the target temperature (such as 28 ℃ for ground heating and 50 ℃ for pipeline insulation). operating steps Using high-precision thermometers (accuracy ± 0.1 ℃) or infrared thermometers, select three representative measuring points in the heating area (such as the center of the room, 1m away from the wall, and corners for ground heating); Pipeline insulation should be selected at areas with dense cable winding, in the middle, and at the end; Record the initial temperature (before power on), and record the temperature of each measuring point every 10 minutes after power on until the temperature stabilizes (continuous temperature fluctuation ≤ 0.5 ℃ for 30 minutes); Calculate the time from the initial temperature to the target temperature and compare it with the standard requirements. compliance standard Ground radiation heating scenario: heating time ≤ 1 hour (from 20 ℃ to 28 ℃); Pipeline insulation scenario: The heating time must meet the design requirements (such as from 10 ℃ to 50 ℃, with a time of ≤ 2 hours, subject to the specific design documents); If the heating rate is too slow (such as exceeding 2 hours), it is necessary to check whether the cable power is insufficient, whether the insulation layer is damaged (heat loss), or whether the cable spacing is too large.   2. Temperature uniformity detection: Verify whether the heat distribution is balanced Temperature uniformity should avoid local overheating or insufficient temperature, and cover the entire heating area. Infrared thermography is commonly used for visual detection. Testing premise The heating cable has been running stably for more than 2 hours, ensuring sufficient heat transfer; Ground heating scenarios require the completion of filling layer construction (such as cement mortar layer) to avoid direct detection of cable surfaces (which may cause errors due to local contact). operating steps Ground heating: Use an infrared thermal imaging device (resolution ≥ 320 × 240) to scan the entire heating area, select measurement points according to a 2m × 2m grid, and cover at least 9 measurement points (such as a 3x3 grid, including corners, edges, and centers); Pipeline insulation: Select a measuring point every 1m along the axial direction of the pipeline, measure the temperature at each point in four directions: up, down, left, and right of the pipeline, and record the temperature at each point; Calculate the difference between the highest and lowest temperatures of all measuring points to determine if they meet the standards. compliance standard Ground heating: The temperature difference between all measuring points is ≤ 3 ℃ (such as 28 ℃ in the center and no less than 25 ℃ at the edges); Pipeline insulation: The temperature difference between measuring points on the same section is ≤ 5 ℃, and the temperature difference between adjacent measuring points in the axial direction is ≤ 3 ℃; If the local temperature difference is too large (such as the temperature in the corner being 5 ℃ lower than the center), it is necessary to check whether the cable spacing is uneven (locally too sparse), whether there are gaps in the insulation layer (heat loss), or whether the thickness of the pipeline insulation layer is insufficient.   3. Temperature control accuracy testing: Verify the linkage effect between the temperature controller and the cable The temperature control accuracy ensures that the system can stably maintain the set temperature, avoiding frequent start stop or temperature drift. Testing premise The temperature controller has completed parameter settings (such as setting a temperature of 28 ℃ with a return difference of 1 ℃), and it is linked normally with the heating cable; Use third-party high-precision temperature measuring equipment (such as platinum resistance thermometers with an accuracy of ± 0.1 ℃) to avoid relying on the built-in display of the thermostat (which may have errors). operating steps Fix the high-precision thermometer probe in the center of the heating area (ground heating buried in the filling layer, pipeline insulation attached to the surface of the pipeline), with a distance of ≥ 50cm from the temperature controller sensor (to avoid mutual interference); Record the temperature displayed by the thermostat and the actual temperature measured by a third-party device, monitor continuously for 4 hours, and record data every 30 minutes; Calculate the difference between the displayed temperature and the measured temperature for each record, and calculate the maximum error. compliance standard Temperature control accuracy error ≤ ± 1 ℃ (if the thermostat displays 28 ℃, the measured temperature should be between 27 ℃ and 29 ℃); If the error exceeds ± 2 ℃, the temperature controller sensor needs to be calibrated (such as repositioning the probe), or the signal connection between the temperature controller and the cable needs to be checked (such as poor contact of the control line).     2、 Auxiliary detection: eliminate hidden problems   1. No local overheating detection Purpose: To avoid local overheating caused by cable overlap or damage (leading to insulation failure); Operation: Use an infrared thermal imaging device to scan the cable laying area, focusing on cable joints, bends, and overlapping hidden dangers (such as the corners of ground heating); Standard: The local maximum temperature shall not exceed 80% of the rated temperature resistance of the cable (such as a cable with a temperature resistance of 120 ℃, the local maximum temperature ≤ 96 ℃), and shall not exceed the safe temperature of the heating object (such as the maximum temperature of the pipeline medium+10 ℃). 2. Power off cooling test (optional) Purpose: To verify whether the system's heat dissipation is normal and eliminate the "heat storage hazard" caused by excessive insulation layer wrapping; Operation: After the heating cable runs stably for 2 hours, cut off the power and record the time for each measuring point to drop from the target temperature to the initial temperature (such as from 28 ℃ to 20 ℃); Standard: The cooling time should meet the design expectations (if the cooling time for ground heating is ≥ 2 hours, it indicates that the insulation layer has good insulation effect; if it drops to 20 ℃ within 1 hour, it is necessary to check whether the insulation layer is damaged).     3、 Testing tools and precautions   1. Essential tools (need to be calibrated and qualified) High precision temperature measurement equipment: infrared thermal imaging instrument (resolution ≥ 320 × 240, temperature measurement range -20 ℃~300 ℃), platinum resistance thermometer (accuracy ± 0.1 ℃); Timing tool: stopwatch or electronic timer (accuracy ± 1 second); Recording tool: Inspection Record Form (indicating the location, time, and temperature values of the measuring points, and signing for confirmation). Precautions Avoid environmental interference: Close doors and windows during detection, prohibit frequent movement of personnel (to avoid air flow affecting temperature), and prohibit placing heavy objects in the heating area in ground heating scenarios (to compress the filling layer and affect heat transfer); Pipeline insulation needs to simulate actual working conditions: if there is a medium (such as hot water) inside the pipeline, the temperature of the medium should be kept stable (such as set at 30 ℃), and then the heating effect of the cable should be tested to avoid interference from temperature fluctuations of the medium; Data retention: After the testing is completed, a "Heating Effect Testing Report for Heating Cables" must be issued, accompanied by infrared thermal imaging images and temperature record sheets, as the basis for acceptance.     The core of accepting the heating effect of the heating cable is to verify it through three major indicators: heating speed, temperature uniformity, and temperature control accuracy, combined with professional tools and standard processes, while also investigating hidden problems such as local overheating and abnormal heat dissipation. If the test does not meet the standard, it is necessary to first investigate the cable power matching, laying spacing, insulation layer quality, and other issues, rectify them, and retest to ensure that the system meets safety and usage requirements.      

The heating rate of the heating cable does not meet the standard, and the core reasons are concentrated in four categories: insufficient power matching, heat transfer loss, installation process defects, and environmental interference. Specific investigations can be conducted according to the following dimensions:     1、 Power matching issue: core cause, insufficient heating capacity   The total power or power density of the insulated heating cable does not meet the design requirements and cannot provide sufficient heat quickly. The total power is lower than the design value Phenomenon: The actual total power of the cable is less than the design value, and the heating capacity is insufficient. Common causes: incorrect cable selection, actual laying length shorter than the design length, and some cables in multi circuit systems not being powered on. Troubleshooting method: Use a power meter to measure the power of a single cable or total circuit, and compare it with the design documents. Uneven distribution of power density Phenomenon: The distance between cables in local areas is too large, the heating power per unit area is insufficient, and the overall temperature rise slows down. Typical scenario: During ground heating, the cable laying in the corners and edges of the wall is too loose, resulting in a slow overall heating up; When insulating pipelines, the spiral winding spacing suddenly widens, and the local heating density is insufficient.       2、 Heat transfer loss: Heat is lost too quickly and cannot be effectively accumulated   The heat is not fully transferred to the controlled object (ground, pipeline), but instead is lost through insulation layers, gaps, etc., resulting in low heating efficiency. Failure of insulation/thermal insulation layer Ground heating scenario: Insufficient insulation layer thickness (such as 20mm in design, 10mm in reality), cracks or loose splicing (not sealed with tape), heat seeps down to the floor slab and cannot accumulate upwards. Pipeline insulation scenario: The insulation cotton is not tightly wrapped around the pipeline, the thickness is insufficient, or there is no outer protective layer, and the heat is carried away by the cold air. Construction defects in the filling layer (ground heating) The thickness of the filling layer (cement mortar) is too thick (such as 50mm in design, 80mm in reality), which prolongs the heat conduction path and significantly prolongs the heating time; The filling layer is not properly cured, there are pores inside, and the thermal conductivity efficiency decreases; Too many stones and impurities are mixed into the filling layer, resulting in poor thermal conductivity and inability to quickly transfer heat to the surface. The cable is not tightly attached to the controlled object When the pipeline is insulated, the cable is not fixed on the surface of the pipeline with aluminum foil tape, resulting in suspension (such as cable detachment caused by pipeline protrusion) and low heat transfer efficiency; When heating on the ground, the cable gets stuck in the gap of the insulation layer and has insufficient contact with the filling layer, which hinders heat transfer.     3、 Installation process and equipment failure: affecting heat output efficiency   Improper installation or equipment malfunction can cause the cable to be unable to output heat properly, indirectly slowing down the heating rate. Partial cable malfunction The internal heating wire of the cable is broken, and the joint is virtual (such as the cold end joint is not welded firmly), resulting in some sections not heating or a decrease in heating power; After the insulation layer of the cable is damaged, water enters, causing a local short circuit and triggering the leakage protection switch to frequently trip, making it impossible to continue heating. Temperature controller setting or linkage failure The set temperature of the thermostat is too low and the hysteresis is too large, resulting in frequent start stop of the cable and inability to continue heating up; Improper positioning of the temperature controller sensor (such as sticking to the surface of the cable, mistakenly measuring high temperature), cutting off the power supply in advance, and the actual room temperature not meeting the standard; The output power of the thermostat is insufficient to drive the cable to operate at full power. Power and wiring issues Insufficient power supply voltage leads to a decrease in the actual power of the cable; The wire diameter of the line is too thin and the wiring terminals are virtual, resulting in excessive line loss, insufficient voltage at the cable end, and reduced heating efficiency.       4、 Environmental interference: Excessive external cooling load offsets heat The low temperature and airflow in the external environment continue to consume the heat generated by the cable, resulting in slow heating. The initial ambient temperature is too low When the initial room temperature is lower than the standard during testing, the cable needs to first offset the cooling load and then raise the temperature to the target temperature, which naturally extends the time. Severe cold source infiltration The doors and windows in the heating area are not sealed, and cold air continues to infiltrate, taking away heat; Ground heating areas located near exterior walls, windows, or exposed pipes outdoors (without anti freezing insulation) can experience rapid heat loss due to cold radiation. Influence of airflow or coverings There are exhaust fans and air conditioning cold air in industrial workshops and large spaces, which accelerate air flow and dissipate heat too quickly; The ground heating area is covered with large carpets and large furniture, which prevents heat from dissipating and accumulates under the coverings, slowing down the surface heating.  

The core of daily maintenance and upkeep of heating seats is to protect the heating element, maintain electrical safety, and extend material life. Targeted measures should be taken according to their different usage scenarios and material characteristics, while avoiding operations that may damage the product. The following are detailed maintenance methods by dimension:       1、 Universal basic maintenance (applicable to all types of heating seats) This type of operation is a prerequisite for ensuring the safe operation of the floor heating seat and needs to be performed before and after each use or regularly. Check before use Electrical safety inspection: Before each power on, check whether the power cord is damaged, whether the plug is loose, and whether there is blackening or oxidation at the wiring. If the above problems exist, stop using immediately and contact after-sales. It is strictly prohibited to disassemble and repair on your own. Appearance inspection: Observe whether there are scratches, bulges, and accumulated stains on the surface of the heating seat. If the surface is damaged, waterproof sealing treatment should be carried out first (special insulation waterproof tape can be applied for household use, and the outer sheath needs to be replaced for industrial use) to prevent moisture and short circuit of the internal heating element. Protection during use Prohibit folding and heavy pressure: Avoid folding, rolling, or placing sharp objects on the heating mat to prevent the internal heating wire from breaking or the heating film from being damaged; Household mattresses should not be powered on when folded, while industrial equipment should ensure a tight fit with the surface of the equipment without any hanging or squeezing. Control usage duration and temperature: Control the duration of single use according to the instructions (recommended for household use not exceeding 8 hours, industrial use should not exceed 24 hours of continuous operation and should be stopped for heat dissipation), to avoid long-term high-temperature operation accelerating material aging; During sleep, it is necessary to set the temperature to low or activate the timer function to reduce the load on the heating element. Clean after use Power off cooling: Before cleaning, the power plug must be unplugged and the hot seat must be completely cooled before operation to prevent high temperature burns or electric shock. Gentle cleaning: Use a wrung out damp cloth to wipe the surface dust. For stubborn stains, dip a small amount of neutral cleaner and gently wipe. Do not use strong acid or alkali cleaners to avoid corroding the surface material; After cleaning, it needs to be dried before storage or use, and should not be exposed to direct sunlight.     2、 Special maintenance for different scenarios Home use scenario (mattress/sofa/bathroom heating mat) Mattress style: Regularly remove the surface cover (if removable) for cleaning, and do not directly wash the heating seat body with water (only wipe it off); When storing, lay flat or roll into a cylinder with a diameter of ≥ 30cm, avoid folding, store in a dry and ventilated place, away from damp wardrobes or floors. Avoid using other heating devices such as electric blankets and hot water bags on the heating seat to prevent damage to the heating element caused by excessive local temperature. Waterproof design for bathroom: After each use, dry the surface water and regularly check whether the IP waterproof sealing strip is aging and cracking. If it cracks, replace the sealing strip to ensure waterproof performance; The splash box of the power socket should be kept closed to prevent water vapor from entering the socket and causing a short circuit.   Industrial scenario (equipment insulation/pipeline heat tracing heating mat) Equipment outer wall design: Regularly check whether the outer insulation layer has fallen off, and if it has fallen off, it should be promptly replenished to reduce heat loss while protecting the heating mat from industrial dust and oil pollution; Every six months, use a multimeter to check the resistance value of the heating seat. If the deviation from the factory value exceeds ± 10%, the machine should be stopped for maintenance to prevent uneven heating. The heating mat that comes into contact with chemical media should be checked quarterly for corrosion spots on the surface fluoroplastic sheath. If it is damaged, it should be replaced immediately to prevent the medium from penetrating into the interior and damaging the heating element. Pipeline heating system: After the winter heating is stopped, it is necessary to clean the frost and impurities on the surface of the pipeline, check whether the fixing buckle of the underground heating seat is loose, reinforce it again, and do a good job of moisture-proof protection; Outdoor pipeline models need to be additionally wrapped with sunscreen and anti freezing protective sleeves to prevent low-temperature cracking in winter and UV aging in summer.   Agricultural scenario (greenhouse soil/seedling box heating mat) Soil burial fee: After each season of planting, dig out the heating mat (avoid violent pulling), clean the soil and roots attached to the surface, rinse with clean water and air dry, check whether the PE waterproof film is damaged, and repair the damaged area with special waterproof glue; Keep away from corrosive materials such as pesticides and fertilizers during storage to prevent material aging. Nursery box model: Regularly wipe the surface with alcohol swabs to disinfect and remove residual roots of seedlings; When storing, place it in a dry cardboard box to prevent rodents and insects from biting the power cord and surface material.     3、 Prevention and emergency response of common faults Core measures for preventing malfunctions Avoid frequent plugging and unplugging of plugs to reduce poor contact and oxidation of plugs; Household models should not use inferior power strips, while industrial models should be equipped with leakage protectors. When not in use for a long time, the power should be unplugged, cleaned and dried before storage. Every 3 months, power on and run for 10 minutes (at low temperature) to activate the heating element and prevent internal components from becoming damp and ineffective. Emergency response If there is any odor, smoke, or local overheating during use, immediately cut off the power, stop using, and contact professional after-sales service. It is strictly prohibited to disassemble on your own; If there is a slight leakage, it is necessary to check whether the socket grounding is normal. If there is no grounding, a grounding device should be installed.     4、 Maintenance taboos It is strictly prohibited to wash or soak the heating mat body with water, even for IPX7 waterproof models, it should not be soaked in water for a long time. It is strictly prohibited to pry or puncture the surface of the heating seat with sharp tools to avoid damaging the internal heating element and circuit. It is strictly prohibited to self wire or replace components when the heating seat malfunctions. Non professional operations may cause safety accidents such as electric shock and fire.