Abstract: A method for controlling a district thermal energy distribution system is presented. The method comprises: determining whether a local pressure difference between a feed line (111) and a return line (112) of a distribution grid (110) is below a predetermined threshold; upon the local pressure difference is determined to be below the predetermined threshold, generating a control signal comprising information instructing a local distribution system (150) to reduce outtake of heat or cold from the distribution grid (110); sending the control signal to a local control unit (140) of the local distribution system (150); and reducing, in response to the control signal, the outtake of heat or cold of the local distribution system (150) from the distribution grid (110). The distribution grid (110) may be a district heating grid or a district cooling grid. Also, a control server and a district thermal energy distribution system is presented.

Abstract: A baffle for a furnace of a heating, ventilation, and air conditioning (HVAC) system includes a mounting flange configured to be secured to a housing of the furnace. The baffle also includes a first panel extending from the mounting flange into an air flow path extending through the furnace and a second panel extending from the first panel toward the housing.

Abstract: An air conditioner indoor unit includes a body including an air outlet, an outer air deflector arranged at the air outlet and configured to open and close the air outlet, and an inner air deflector arranged at an inner side of the outer air deflector. The outer air deflector includes a plurality of first vent holes penetrating the outer air deflector in a thickness direction of the outer air deflector. The inner air deflector includes a plurality of second vent holes penetrating the inner air deflector in a thickness direction of the inner air deflector.

Abstract: Systems and methods for cooling a datacenter are disclosed. In at least one embodiment, one or more flow controllers is associated with a cold plate and with a thermosyphon condenser that is elevated with respect to a cold plate so that two-phase fluid is enabled for gravity-assisted downflow in a liquid phase to a cold plate for absorption of heat and is enabled for buoyancy-driven upflow through a riser tube into a thermosyphon condenser for dissipation of heat of at least one computing device.

Abstract: A bed has a mattress. A first wireless charging array is positioned on a top side of the mattress nearer a head of the mattress. A pillow is configured to be positioned atop the first wireless charging array. The pillow includes a second wireless charging array located on an underside of a pillow. The second wireless charging array is configured to receive energy from the first wireless charging array. A companion device is configured to use the energy. An energy storage device is within the pillow. The energy storage device is configured to store charge received by the first wireless charging array. The energy storage device is configured to supply power to the companion device.

Abstract: The invention provides a two-phase flow active and passive multi-level data center cabinet cooling device and method, wherein the system includes a cabinet cooling device, a condensate system, a waste heat recovery device, a liquid reservoir, a liquid pump, a gas chamber, a fluid working medium, and a corresponding pipeline. The system comprise a closed loop, the loop is filled with nitrogen to maintain a low pressure state, and the pipeline fluid is driven by the liquid pump to flow; the gas chamber maintains a relatively stable air pressure in the two-phase flow loop; the liquid reservoir is connected with the gas chamber, providing an enough gas space to make a phase change occur more easily; the cabinet cooling device can be switched between an active mode and a passive mode to minimize PUE under good heat dissipation capability.

Abstract: An electric vehicle cooling system, including: a first radiator installed at a vehicle and configured to cool a power unit driven by electrical power; and a second radiator installed at the vehicle, disposed at least at one side in a vehicle width direction, or another side in the vehicle width direction, of the first radiator so as not to overlap with the first radiator as viewed along a vehicle front-rear direction, and configured to cool an autonomous driving control device configured to control autonomous driving of the vehicle.

Abstract: An electric vehicle cooling system, including: a first radiator installed at a vehicle and configured to cool a power unit driven by electrical power; and a second radiator installed at the vehicle, disposed at a vehicle front side of the first radiator, and configured to cool an autonomous driving control device configured to control autonomous driving of the vehicle.

Abstract: A liquid supply unit includes a tank having an inner space for storing the liquid, an inlet line for supplying the liquid from the liquid supply source to the inner space and having an inlet valve installed thereon, an outlet line for supplying the liquid from the tank to a nozzle or for recollecting the liquid to the tank and having an outlet valve installed thereon, a gas supply line for supplying a gas to the inner space and having a gas control valve installed thereon, an exhaust line for exhausting the inner space and having an exhaust valve installed thereon, a circulation line for circulating the liquid stored in the inner space, and a controller controlling the liquid supply unit so that the circulation line is pressurized while the liquid is supplied to the inner space.

Abstract: The cooling systems and methods of the present disclosure involve modular fluid coolers and chillers configured for optimal power and water use based on environmental conditions and client requirements. The fluid coolers include wet media, a first fluid circuit for distributing fluid across wet media, an air to fluid heat exchanger, and an air to refrigerant heat exchanger. The chillers, which are fluidly coupled to the fluid coolers via pipe cages, include a second fluid circuit in fluid communication with the air to fluid heat exchanger and a refrigerant circuit in thermal communication with the second fluid circuit and in fluid communication with the air to refrigerant heat exchanger. Pipe cages are coupled together to allow for expansion of the cooling system when additional cooling capacity is needed. The fluid coolers and chillers are configured to selectively operate in wet or dry free cooling mode, partial free cooling mode, or mechanical cooling mode.

Abstract: An aircraft engine includes a core gas path through which a core gas flow flows, an exhaust duct receiving the core gas flow, an air-cooled heat exchanger disposed in a heat exchanger duct having an air inlet providing cooling air to the air-cooled heat exchanger and an air outlet in fluid communication with the exhaust duct, and a cover disposed in the heat exchanger duct downstream of the air-cooled heat exchanger. The cover is movable between an open position, in which the cover allows the cooling air to flow through the air outlet into the exhaust duct, and a closed position, in which the cover substantially blocks the air outlet. The cover is operable to move from the open position to the closed position at a predetermined temperature of the cover.

Abstract: The present invention discloses a two-phase immersion-cooling micro-grooved boiler, which is mainly used for heat dissipation of heat generating objects. The boiler comprises a heat transfer member and a capillary layer positioned in tight contact with a surface of the heat transfer member. The capillary layer has an array of micro-grooves which divides the capillary layer into a plurality of heat dissipating units. The bottom surface of the micro-grooves is coated with a thermal resistance layer. While the boiler operates, the working liquid can flow into the heat dissipating units from the sidewall of the micro-grooves without being blocked from contact with the heat transfer member by boiling-triggered bubbles. As a result, dry-out of the heat transfer member can be avoided, thereby improving the heat exchange efficiency of the boiler and the flow-back rate of the working fluid.

Abstract: This disclosure relates to a liquid-cooling device that includes a liquid block and a radiator. The liquid block is in thermal contact with an interface card. The radiator includes a first tank, a second tank, and a heat dissipation channel structure. The first tank and the second tank respectively have a first chamber and a second chamber. The heat dissipation channel structure includes a plurality of liquid transmission components. The first chamber and the second chamber are respectively connected to two opposite sides of the heat dissipation channel structure. Each of the liquid transmission components has an end in fluid communication with the first chamber of the first tank and another end in fluid communication with the second chamber of the second tank. The first chamber and the second chamber are in fluid communication with the liquid block to form a cooling cycle.

Abstract: Apparatus for tensioning pliable airducts while supporting internal HVAC components are disclosed. An airduct system includes an airduct having an elongate tubular wall of a pliable material. The airduct system further includes a frame disposable inside the tubular wall of the airduct, the frame including a hoop to support the tubular wall in a radial direction, the hoop to define an opening to provide passage of a flow of air along a length of the airduct. The airduct system also includes an HVAC component disposable within the tubular wall of the airduct, the HVAC component to be attached to and supported by the frame inside the airduct, the HVAC component to adjust a characteristic of the air.

Abstract: A cooling arrangement for a gas turbine engine according to an example of the present disclosure includes, among other things, an offtake duct that has an offtake inlet coupled to a cooling source, the offtake duct defining a throat, and a valve downstream of the throat. The valve couples the offtake duct and a first cooling flow path. The valve is operable to selectively modulate flow through the offtake duct. A bleed passage includes a bleed inlet coupling the offtake duct and a second cooling flow path. The bleed inlet is defined at a location between the offtake inlet and the throat, inclusive. A method of cooling a propulsion system is also disclosed.

Abstract: An air conditioning system (1) has a heater unit (3) providing a hot water flow (7) and receiving a hot water return (31) in hot water loop, a chiller unit (5) providing a cold water flow (13) and receiving a cold water return (33) in a cold water loop, one or more air to water heat exchangers (17), and one or more control valves (11), each control valve (11) associated with one of the air to water heat exchangers (17) and arranged to receive the hot water flow (7) and cold water flow (13), selectively provide the flow from a one of the hot water loop or cold water loop to the associated air to water heat exchanger (17), receive a return from the associated air to water heat exchanger (17), and selectively provide the return from the associated air to water heat exchanger (17) to the return of the one of the hot water loop or cold water loop.

Abstract: Provided is a gas-liquid separator, including a connection pipe connected to a refrigerant pipe in the evaporator, the refrigerant pipe in which a two-phase refrigerant flows, a header connected to the connection pipe, wherein a gas refrigerant separated from the two-phase refrigerant flows inside the header, a bypass pipe connected to the header to guide a flow of the gas refrigerant to a compressor, a flow rate control valve installed at the bypass pipe, and a controller configured to control opening and closing of the flow rate control valve based on whether a preset condition is satisfied.

Abstract: An exemplary system is for a facility including a first heating/cooling zone and a water delivery system configured to deliver domestic water to a point of water use. The system generally includes a facility loop having a facility loop refrigerant flowing therethrough, a first zone heat pump configured to transfer thermal energy between the facility loop refrigerant and the first heating/cooling zone, and a first water-source heat pump configured to transfer thermal energy between domestic water upstream of the point of water use and the facility loop refrigerant.

Abstract: Systems and techniques are described herein for an insulation system that utilizes a treated gas, such as water vapor, to fill an at least partially transparent cavity that is part of a structure, to provide insulating properties and/or changes in exposure to the sun for a space, proximate to the structure. In some aspects, an insulation system may include a treated gas generation system, which includes at least one of a heating element, a cooling element, or a diffusing element for treating the gas. The system may also include a gas movement system in communication with the gas generation system. The system may further include a gas conduit system in communication with the gas movement system, where the gas movement system causes the treated to be injected into the gas conduit system to change insulation and/or sun exposure characteristics of a space in proximity to the gas conduit system.

Abstract: A battery assembly according to a non-limiting aspect of the present disclosure includes, among other things, an array of battery cells, and a thermal exchange plate assembly adjacent the array. The thermal exchange plate assembly includes an inlet, an outlet, a main channel, and a bypass channel configured to direct fluid from the inlet to the outlet while substantially bypassing the main channel.

Abstract: A two-phase liquid immersion cooling system is described in which heat generating computer components cause a dielectric fluid in its liquid phase to vaporize. Advantageously an absorption/desorption unit is employed having a carbon element and a controller configured to regulate the absorption unit.

Abstract: An oil temperature control assembly mounts on a vehicle's operating group fluidically connected to an oil circulation system and a cooling system. A heat exchanger has plate-shaped exchanger elements defining reciprocally alternate ducts through which oil and refrigerant fluid flow, and a support and oil control device. The support and oil control device has a plate-shaped base element including the oil inlet and outlet ducts having a first surface in contact and engageable by the heat exchanger and a second opposite surface. The support and oil control device includes a control group having a housing body projecting from the first surface next to the heat exchanger having a housing cavity fluidically connected to the inlet and outlet ducts and an exchanger duct and a valve member in the housing cavity including an obturator element and a control element which moves the obturator element according to oil operating conditions.

Abstract: Provided is an air conditioner capable of improving heating performance in a cold region by reducing a refrigerant pressure loss in an outdoor heat exchanger in a heating operation. The air conditioner includes a compressor, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger. The outdoor heat exchanger may include a plurality of unit channels into which a refrigerant channel is partitioned, and a separating device installed in each of the plurality of unit channels and configured to separate a liquid refrigerant component and a vapor refrigerant component in each of the plurality of unit channels in a heating operation. The air conditioner may further include a compressor suction channel connecting a heating-operation outlet of the outdoor heat exchanger and an inlet of the compressor, and a bypass pipe connecting the separating device and the compressor suction channel.

Abstract: A smelting vessel includes a plurality of heat pipes (21) positioned in a refractory lining of at least a part of the hearth (9) for cooling at least a part of the refractory lining. At least one of the heat pipes includes (a) a liquid phase of a heat transfer fluid, typically water, in a lower section of the heat pipe and (b) a vapor phase of the heat transfer fluid, typically steam, in an upper section of the heat pipe. The heat pipe also includes a vent to allow vapour phase to escape from the heat pipe to reduce the pressure or the temperature within the heat pipe when the vapour pressure or the temperature in the heat pipe exceeds a predetermined threshold pressure or temperature.

Abstract: A grey water heat recovery apparatus has first and second passes in counter-flow orientation. The hot side is grey water. The cold side is fresh water. It extracts heat from the grey water. The fresh water is carried in tubing bundles in series immersed in grey water sumps in cylindrical plastic, mild steel, or stainless steel pipe. Both ends of the fresh water bundle assembly extend from the same upper end pipe closure, without a pressurized line wall penetration in the walls of the pipe. There is a non-electrically conductive barrier between the fresh water and grey water flow paths. The apparatus has a leak detection circuit and co-operable bypass valves. The tube bundle is wider at the top than at the bottom. The lower manifold has grey water passages between the centering ears. The entire assembly is enclosed in a unitary external housing with easily accessible connection fittings.

Abstract: A vehicle heating/cooling system has first and second fluid circulation loops for circulating engine coolant and automotive fluid. A first heat exchanger transfers heat from the coolant to air for the passenger compartment. A second heat exchanger transfers heat between the coolant and automotive fluid. A first valve has first and second inlets for receiving coolant from hot and cold coolant sources, and an outlet for discharging coolant to the second heat exchanger. A second valve has an inlet for receiving coolant from the first coolant source, and an outlet for discharging coolant to the first inlet of the first valve. The valve positions change with temperature of the coolant and the automotive fluid, providing preferential heating of the passenger compartment during cold start-up of the vehicle. The second heat exchanger and valves may be provided in a temperature control module.

Abstract: An outlet manifold is provided and includes an outlet portion having first and second sides and an inlet portion to which the outlet portion is fluidly coupled. The inlet portion has first and second sides corresponding to the first and second sides of the outlet portion. Each of the first and second sides of the inlet portion includes one or more tubular members connectable with corresponding tube joints and a mixing chamber fluidly interposed between each of the one or more tubular members and the outlet portion.

Abstract: A heat dissipation device includes two connected components and a flexible metal conduit. Each connected component is selected from a manifold, a quick connector, an evaporator, a condenser or a pump. The two connected components are in communication with each other through the flexible metal conduit. The use of the flexible metal conduit is effective to absorb the designing tolerance. In addition, the flexible metal conduit is recyclable.

Abstract: A housing has a heat exchange flow passage which branches from the main exhaust gas flow passage and converges to the main exhaust gas flow passage through the heat exchanger. The valve has a valve pipe constituting the main exhaust gas flow passage in the exhaust pipe and a valve body which rotates to contact a seat part downstream of the valve pipe in an exhaust gas flow direction such that the exhaust gas flows to the heat exchange flow passage. An out port of the heat exchange flow passage which converges to the main exhaust gas flow passage is disposed upstream of a downstream side distal end of the valve pipe in the exhaust gas flow direction, and the downstream side distal end of the valve pipe in the exhaust gas flow direction is disposed upstream of a downstream side distal end of the heat exchanger in the exhaust gas flow direction.

Abstract: A shell-and-tube equipment comprises an inlet channel for a first fluid to be cooled, an outlet channel for the cooled first fluid, a plurality of tube-bundle tubes, at least a tube-sheet, a shell enclosing the tube-bundle tubes and a bypass system for controlling the outlet temperature of the cooled first fluid at a target value. The bypass system comprises a box installed inside the outlet channel. The box is provided with an opening or conduit, a regulating valve and a box tube-sheet. The box is further provided with bypass bayonet tubes. Each bayonet tube extends from the box tube-sheet to a point in between a first open end and a second open end of the tube-bundle tubes and is partially inserted into a corresponding tube-bundle tube, so as an annular gap in between each tube-bundle tube and the corresponding bayonet tube is formed.

Abstract: A method and apparatus for pool boiling includes introducing a fluid into a chamber of a housing which has one or more protruding features. One or more diverters extend at least partially across the one or more protruding features in the chamber. One or more bubbles are formed in the fluid in the chamber as a result of bubble nucleation. At least one of growth and motion of the one or more of the bubbles are diverted with the one or more diverters to generate additional localized motion of the fluid along at least one of the one or more protruding features and other surfaces in the chamber of the housing to at least of transfer additional heat to the liquid and increase the critical heal flux limit.

Abstract: An air conditioner includes a heat exchanger configured to exchange heat with air introduced into a housing and a blowing fan configured to blow the air which is heat-exchanged with the heat exchanger to outside of the housing. The air conditioner may control a first and a second doors configured to open or close a first and second blowing ports provided in the housing and a guide blade configured to control paths in the housing, so that the air conditioner may blow the air of various flow.

Abstract: A vapor chamber and a manufacturing method thereof are provided. The vapor chamber includes a housing, a capillary structure, at least two liquid-filling and gas-discharging pipes and a working fluid; the housing has a bottom housing plate and a top housing plate correspondingly engaged and sealed with the bottom housing plate, and a single chamber is formed between the top housing plate and the bottom housing plate; the capillary structure is disposed in the single chamber; each of the liquid-filling and gas-discharging pipes is allowed to penetrate into the housing and communicate with the single chamber; and the working fluid is disposed in the single chamber. Accordingly, the working fluid can be evenly and widely distributed in the single chamber.

Abstract: A second flow path switching apparatus includes a first distribution apparatus configured to distribute refrigerant to a plurality of refrigerant paths in a first heat exchange portion, a second distribution apparatus configured to distribute refrigerant to the plurality of refrigerant paths in the first heat exchange portion and a second heat exchange portion, and a switch portion configured to switch connection of a refrigerant inlet of a first heat exchange apparatus to the first distribution apparatus or to the second distribution apparatus and switch whether refrigerant which flows out of a refrigerant outlet of the first heat exchange portion is allowed to pass through the second heat exchange portion or to merge with refrigerant which flows out of a refrigerant outlet of the second heat exchange portion in accordance with whether an order of circulation of the refrigerant is a first order (cooling) or a second order (heating).

Abstract: A side slit of a core plate of a heat exchanger reaches a sealing surface. The core plate has a rib which is formed on a bottom plate across a protruding portion. The rib communicates to a cavity above the sealing surface. An end slit formed on an end wall of the core plate reaches the sealing surface. A first joining tab is formed between two end slits. The first joining tab is joined to a second joining tab on a reinforce plate. The side slit and the rib enable deformation of the core plate. The end slit enables deformation of the first joining tab in a tilting manner.

Abstract: A heat exchanger is configured to perform heat exchange by boiling a liquid by heat transfer from a heat source to the liquid through a heat transfer member. In the heat exchanger, a first heat conduction region and a second heat conduction region are alternately provided in a form of stripes on a surface on a side that contacts the liquid such that the liquid boils via a heat transfer member.

Abstract: A once-through dry adiabatic cooler having an integrated factory installed air pre-cooler system that is mechanized to move from a shipping position to an operational position.

Abstract: A gas displacement assembly includes a storage container, a pump that pumps a pressurized gas material into the storage container, a cooling chamber that houses a coolant and cools the gas material to a cryogenic temperature, and a coolant line that transports coolant through the cooling chamber to cool the gas material.

Abstract: Provided is an electrical junction box in which it is possible to prevent a switching element from catching fire. An electrical junction box according to one aspect of the present disclosure is an electrical junction box including: a circuit substrate on which a switching element is mounted on one side of the circuit substrate; and a housing member that houses the circuit substrate. The housing member further houses a thermally expandable expansion material member. When the temperature of the switching element is low, the expansion material member is spaced apart from the circuit substrate and the switching element, and is disposed at a position opposing the one side. When the temperature of the switching element is high, the switching element is embedded in the thermally expanded expansion material member.

Abstract: A system and method of using a source of low-pressure refrigerant for a cryotherapy procedure. The system may generally include a fluid reservoir and a fluid flow path in thermal exchange with the fluid reservoir, the fluid flow path including a thermal exchange device in thermal exchange with the fluid reservoir, a compressor in fluid communication with the thermal exchange device, a condenser, a reversing valve located between the compressor and the condenser, and an expansion valve located between the condenser and the thermal exchange device. The method may include transferring a low-pressure refrigerant to a first fluid reservoir, reducing the temperature of the refrigerant within the first fluid reservoir, increasing the temperature of the refrigerant within the first fluid reservoir, and transferring the pressurized refrigerant from the first fluid reservoir to a second fluid reservoir.

Abstract: In one embodiment of the present disclosure, a device is disclosed comprising a macroscopic thermal body and an extraction structure that is electromagnetically-coupled to the thermal emitting area of the thermal body. The macroscopic thermal body having a thermal emitting area, and the extraction structure configured and arranged to facilitate emission from, or receipt to the thermal emitting area that exceeds a theoretical, Stefan-Boltzmann, emission limit for a blackbody having the same thermal emitting area as the thermal body.

Abstract: Disclosed herein is a baffle for regulating air flow around an object. The baffle can be of unitary construction and can be made by a single shot injection molding process. The baffle can have an edge portion that is more flexible than the base portion. The baffle has also can have a base portion with a base portion thickness and an edge portion with an edge portion thickness that is less than the base portion thickness. A method of making a baffle by an injection molding process is also disclosed.

Abstract: A hybrid wet/dry cooling tower and novel splash fill material are provided. In one embodiment, the cooling tower includes a wet cooling section having a draft fan disposed above the wet section for drawing air through the wet section to cool liquid traversing the wet section. The cooling tower also includes a dry cooling section disposed laterally adjacent the wet section and configured to enable the draft fan to draw air through the dry section. In another embodiment, the dry cooling section has one or more added draft fan(s) for drawing air through the dry section with or without operation of the draft fan disposed above the wet section. In other embodiments, different structures and configurations of plastic splash fill material are described.

Abstract: A pin fin heat sink includes a plurality of pin fins extending from a base plate, at least one of the plurality of pin fins defining a hollow portion therein. The heat sink also includes a phase change material sealed within the at least one pin fin to absorb transient thermal loads that the pin fin is subjected to.

Abstract: A chip resistor includes a resistive element, a pair of electrodes, and heat radiator plates. The resistive element is made of a plate-shaped metal. The pair of electrodes is formed on both ends of a first surface of the resistive element. The heat radiator plates are fastened to a second surface of the resistive element and are disposed spaced apart from each other via a gap therebetween.

Abstract: A compressed vaporous discharge stream is de-superheated in a de-superheater system. The de-superheater system comprises a de-superheater heat exchanger configured to bring at least a portion of the compressed vaporous discharge stream in indirect heat exchanging contact with an ambient stream. A de-superheater bypass line comprising an temperature-controlled valve is configured to selectively bypass the de-superheater heat exchanger. A combiner is configured downstream of the de-superheater heat exchanger for rejoining the bypass portion with the portion of the compressed vaporous discharge stream that has passed through the de-superheater heat exchanger. A mixer is configured downstream of said combiner, to receive and mix the rejoined stream, and discharge the rejoined stream into a de-superheater discharge conduit as a de-superheated stream.

Abstract: An ammonia stripper has an aerator and heat exchanger tubing in a tank. The aerator and coil are preferably attached to a frame to form a removable cassette. The cassette may also include a lid for the tank. The tank is preferably rectangular and optionally can be made with the dimensions of a standard shipping container. In a process, water flows through the tank while air bubbles are produced through the aerator. A heating medium such as water flows through the heat exchanger tubing. A gas containing ammonia is withdrawn from a headspace of the tank.

Abstract: A heat storage apparatus according to the present disclosure includes a casing, a heat storage material, and movable components. An internal space in the casing is partitioned into a plurality of spaces. The heat storage material is located in each of the plurality of spaces. At least one movable component is disposed in contact with the heat storage material in each of the plurality of spaces, and is capable of changing a position thereof relative to a position of the casing as time proceeds.

Abstract: An indirect dry cooling system suitable for steam condensing applications in a power plant Rankine cycle includes an air blast chiller having a plurality of interconnected modular cooler cells. Each cell includes a blower and tube bundle including inlet headers, outlet headers, and plurality of tubes extending between the headers. In one embodiment, the tube bundles form an A-frame cell construction being structurally self-supporting from a base. Each of the tubes may be finned. Cooling water circulating in a closed flow loop on the tube side between the air blast chiller and turbine steam condenser is cooled by ambient air blown through the tube bundles. The cooled water flows through a second tube bundle in the condenser which condenses steam. The heated cooling water returns through the air blast chiller to complete the cooling water cycle.

Abstract: A device for measuring an electric field in a conducting medium, including: two electrodes separated by a volume of an insulating material; a current measurement device; a voltage measurement device; and a switch enabling to alternately connect the current measurement device and the voltage measurement device between the electrodes.