KR101517205B1 - Epoxy resin molded case potential transformer and current transformer metering out fit molded case with a built-in - Google Patents

Abstract

The present invention relates to a transformer for mold case metering. After manufacturing a dry-type transformer of a VPI method and a mold case of epoxy resin, a transformer for mold case metering is manufactured by a method of embedding a VPI transformer in the epoxy resin case. Thereby, to manufacture a transformer for mold case metering which has superior insulating properties without using expensive vacuum epoxy mold equipment, the dry-type transformer (PT) of a VPI method and CT is embedded in an epoxy resin case. Dry air or mixture gas is filled in a sub-insulating medium. The case includes a VPI transformer which comprises a current transformer for metering formed by a VPI (Vacuum Pressure Impregnation) wire and a transformer for metering; and a case which is made of epoxy resin for embedding the VPI transformer. After the case and the VPI transformer are manufactured, the VPI transformer is embedded in the installation position of the case without using a separate insulating material, so that a transformer for mold metering capable of insulation can be manufactured.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded case case transformer in which a transformer (PT) and a current transformer (CT) are embedded in an epoxy resin molded case.

The present invention relates to a metering out fit (MOF) for an epoxy resin case instrument having a transformer (PT) and a current transformer (CT) embedded in a case molded of a resin such as an epoxy resin, (CT), transformer (PT), etc. are built in the epoxy resin molding case and dry air or mixed gas is filled into the inside with auxiliary insulating medium. The present invention relates to a transformer for environmentally friendly mold instruments, which can manufacture a transformer for a mold instrument excellent in insulation performance without using an expensive vacuum epoxy mold facility by producing a transformer.

Generally, the electric power distribution system is provided with electric facilities such as a transformer, a switch device, and other safety devices for operation and control of a power plant, a substation, distribution of electric power, and operation of the electric motor.

The power distribution system is provided with a power transformer (MOF) (three-phase transformer) for measuring the amount of electric power. The instrument transformer is an inflow type, epoxy mold type, and gas type which is filled with insulating oil (insulating oil), and a current transformer (CT) which transforms the current of a high voltage / high current circuit into a small current necessary for a meter or a relay, And a potential transformer (PT) that converts the voltage to a low voltage required for the meter or relay.

The MOF using the insulating oil has a maximum temperature rise limit of 90 ° C., has a good flame retardancy, good water retention, and can be recycled. However, since the waste insulating oil becomes an industrial waste, the environment- Is an ordinary, and uses an insulation mechanism that is impregnated with insulating oil and insulates it. Resistance to partial discharge is normal, and a metallic insulating oil tank is used for the external appearance. The structure is composed of a transformer (CT) and a transformer (PT) built in a metal tank and insulating between the equipment and the metal case with insulating oil. Separate ceramic or epoxy bushings are required for connection to external high voltage conductors.

In order to improve the insulation performance against the inflow-type MOF, the maximum temperature rise limit of the epoxy-resin-impregnated mold MOF is 130 ° C. to 150 ° C. and exhibits excellent characteristics in the flame retardancy. However, since the outer case and the transformer are integrally molded with the epoxy resin, there is a disadvantage in that it can not be repaired if defects occur. The insulation between the conductor and the core (core) and the primary / secondary winding is molded by epoxy resin, so the insulation performance is excellent and the insulation mechanism called epoxy resin mold insulation is used. Since the outer case and the transformer are integrally molded with the epoxy resin, there is a risk of cracking due to different expansion coefficients. Since the outer case and the transformer are integrally molded by the vacuum impregnation with the epoxy resin, the process is difficult and bubbles or cracks are generated between the releasing materials, which may cause partial discharge. The outer case, the transformer and the CT are integrally vacuum impregnated with the epoxy resin and molded.

The prior art for a mold-type instrument transformer is disclosed in the following Patent Document 1: Korean Patent Registration No. 10-0787964 (registered on December 14, 2007).

In the prior art disclosed in Patent Document 1, a capacitor for an auxiliary power supply and a sensor for detecting a partial discharge (PD) are incorporated in ECT and EVT, which are electronic transformers, and they are molded by an outdoor epoxy resin, The present invention provides a high-voltage outdoor epoxy resin mold type electronic MOF that minimizes the environmental impact, estimates the failure by incorporating a partial discharge detection sensor for prevention diagnosis monitoring, and ensures reliability and stability.

Korea Registered Patent Registration No. 10-0787964 (Registered on December 14, 2007)

However, since the above-described conventional technology has a structure in which the outer case, the transformer and the current transformer CT are integrally molded by the vacuum impregnation method, the insulation performance is excellent, while the outer case and the transformer are molded integrally with the epoxy resin It is impossible to repair it when it is defective and it is impossible to disassemble it at the time of disposal. Therefore, it is disadvantageous to dispose of the whole as industrial waste, and there is a risk of cracking due to different expansion coefficient, process is difficult and bubbles or cracks There is a possibility that a partial discharge may occur.

It is an object of the present invention to propose a method of manufacturing a transformer and a transformer of a VPI method by separately forming a case formed of an epoxy resin or the like and a transformer and a transformer of a VPI method, And a transformer for a mold device by making a transformer for a mold instrument by making a built-in transformer. By doing so, it is possible to manufacture a transformer for a mold instrument with excellent insulation performance without using an expensive vacuum epoxy molding equipment, And a dry transformer (PT) such as a dry type transformer (PT) or the like, and the DRY air or the mixed gas is filled with an auxiliary insulating medium.

Another object of the present invention is to provide a transformer for a mold instrument incorporating a dry transformer and a current transformer of environmentally friendly VPI method by incinerating the aramid insulation paper used for manufacturing the VPI transformer at the time of disposal and recycling the copper wire and the core core etc. will be.

It is another object of the present invention to provide a space between an inner wall of an epoxy resin molded case and a built-in transformer, a current transformer and other internal components, thereby eliminating interference between dissimilar materials having different expansion coefficients, Which is molded with an epoxy resin.

It is still another object of the present invention to provide a transformer and a current transformer manufactured by the VPI method and a transformer and a current transformer inside the case molded of epoxy resin separately from the case of the epoxy resin, It is possible to remove bubbles or cracks between materials, and it is possible to install dry transformer (PT) of CT and VPI method inside epoxy resin molded case which is excellent in partial discharge, and to fill DRY air or mixed gas with auxiliary insulating medium The present invention also provides a transformer for a mold instrument.

It is another object of the present invention to provide a method and apparatus for monitoring the temperature rise due to overheating and overloading of the epoxy resin inside the case and the phase of the main conductor and to diagnose the abnormality by using a self- The present invention is to provide a transformer for a mold instrument in which a dry transformer (PT) of the VPI method is built in an epoxy resin molding case and the DRY air or a mixed gas is filled with an auxiliary insulating medium.

In order to achieve the above-mentioned object, there is provided a transformer for a mold instrument, which comprises a dry transformer (PT) and a current transformer of the VPI method according to the present invention and is manufactured by filling a dry air or a mixed gas with an auxiliary insulating medium ; And a case formed of an epoxy resin for embedding the transformer, the current transformer and the like;

The case and the transformer and the current transformer of the VPI method are manufactured respectively and then the transformer and the current transformer are embedded in the case at the installation position and the molded case made of an epoxy resin is insulated Thereby fabricating a transformer.

The case may include an upper case for incorporating the instrument current transformer therein; And a lower case for incorporating the instrument transformer, wherein the upper case and the lower case are combined and then packed by an O-ring.

In this case, the case includes a valve for introducing the auxiliary insulating material, and the auxiliary insulating material is characterized by using dry air or a mixed gas.

The case includes a temperature detection sensor for detecting a temperature, an image formation voltage detection sensor for detecting an image formation voltage, And a connector for externally outputting the temperature and the imaging voltage value detected by the temperature detection sensor and the imaging voltage detection sensor, respectively.

The case may further include a control device for generating an alarm for overheating and image formation at the detected temperature and imaging voltage.

The controller may include: a signal input unit receiving an output signal of the temperature detection sensor and the image forming voltage detection sensor; A power supply unit for controlling power supplied from the signal input unit; An amplifying unit amplifying each detection signal output from the signal input unit; A micro control unit which is driven by a power supply of the power supply unit and analyzes an output signal of the amplification unit to determine whether the image is in phase with the temperature, controls the temperature and image formation display, and generates an alarm for overheating and image formation; And a status display unit for displaying a temperature and an image forming state under the control of the micro control unit.

The control unit may include an alarm output unit for generating an alarm upon occurrence of any one of overheating and image formation under the control of the micro control unit; An overheat alarm contact output unit for outputting an overheat alarm contact under the control of the micro control unit; And an image forming alarm contact output unit for outputting image forming alarm contacts under the control of the micro control unit.

The status display unit includes a temperature display unit for displaying temperature, and an image display unit for displaying whether or not the image is formed.

According to the present invention, a transformer and a current transformer of a VPI method are separately manufactured from a case molded of an epoxy resin or the like, and then a transformer and a current transformer are embedded in the epoxy resin case. Thus, an expensive vacuum epoxy mold It is possible to fabricate a transformer for a mold instrument having excellent insulation performance without using a facility.

In addition, according to the present invention, there is an advantage that an aramid insulating paper used for manufacturing a VPI transformer at the time of disposal is incinerated, and a copper wire and an iron core are recycled, thereby providing an environmentally friendly transformer for a mold instrument.

In addition, according to the present invention, by forming a space between the inner wall surface of the case molded of epoxy resin and the built-in transformer, the current transformer, and other internal components, interference between dissimilar materials having different expansion coefficients can be eliminated, It is possible to provide a transformer for a mold instrument excellent in partial discharge.

According to the present invention, the temperature rise due to overheating and overload of the inside of the case of the epoxy resin and the phase of the main conductor are monitored to perform self-diagnosis, and an alarm device There are advantages to be able to.

FIG. 1 is a schematic diagram of a mold transformer for a molding machine in which a dry transformer (PT) of the VPI method is embedded in an epoxy resin molded case according to a preferred embodiment of the present invention and DRY air or a mixed gas is filled in the inside with an auxiliary insulating medium Degree,
FIG. 2 is a cross-sectional view of a mold instrument transformer in which a dry transformer (PT) of a VPI method is embedded in an epoxy resin molded case according to a preferred embodiment of the present invention, and DRY air or a mixed gas is filled in the cavity with an auxiliary insulating medium,
Fig. 3 is a detailed configuration of a control device mounted in a mold-type transformer in which a dry transformer (PT) of the VPI method is embedded in the epoxy resin molding case of Fig. 2 and DRY air or a gas mixture is filled in the inside with an auxiliary insulating medium Degree.

Hereinafter, a dry transformer (PT) or the like of the VPI method is embedded in an epoxy resin molded case according to a preferred embodiment of the present invention, and a mold instrument transformer filled with DRY air or a mixed gas as an auxiliary insulating medium is shown Will be described in detail with reference to FIG.

FIG. 1 is a schematic configuration diagram of a mold instrument transformer according to a preferred embodiment of the present invention, and is a transformer for a three-phase (R, S, T) instrument. The three-phase instrument transformer includes an R-phase mold instrument transformer 100, an S-phase mold instrument transformer 200, and a T-phase mold instrument transformer 300.

Hereinafter, only the transformer 100 for an R-phase mold instrument will be described for convenience of explanation.

The R phase mold meter transformer 100 includes a VPI dry transformer 130 formed by a meter current transformer 110 and a meter transformer 120; And a case 140 formed of an epoxy resin for embedding the VPI transformer 130 therein.

The case 140 includes an upper case 141 for incorporating the instrument current transformer 110 therein; And a lower case 142 for incorporating the instrument transformer 120. The upper case 141 and the lower case 142 are combined and then packed by an O-ring 150. FIG. The upper case 141 and the lower case 142 are preferably made of epoxy resin, but the present invention is not limited thereto. The present invention is also applicable to a case in which an insulating material such as an epoxy resin, that is, All insulation materials can be used.

The instrument current transformer 110 includes a high voltage winding 111, a low voltage winding 112, and a core 113.

In addition, the instrument transformer 120 includes a high-voltage winding 121, a low-voltage winding 122, and a core 123. Wherein the high voltage winding 121 is preferably implemented as a VPI winding applied to the VPI transformer.

A valve 160 for introducing an auxiliary insulating material is mounted on the lower case 142. Here, the auxiliary insulating material is preferably dry air or a mixed gas.

In the case 130, a temperature detection sensor 171 for detecting a temperature, an image formation voltage detection sensor 172 for detecting an image formation voltage, a temperature detection sensor 171 and an image formation voltage detection sensor 172, A connector 180 for outputting the detected temperature and an image forming voltage value to the outside, and a controller 190 for generating an alarm about overheating and image formation at the detected temperature and image forming voltage.

The control unit 190 includes a signal input unit 191 receiving the output signals of the temperature detection sensor 171 and the imaging voltage detection sensor 172; A power control unit 192 for controlling power supplied from the signal input unit 191; An amplifying unit 193 for amplifying each detection signal output from the signal input unit 191; Is driven by the power supply of the power control unit 192 and analyzes the output signal of the amplifying unit 193 to determine whether the image is in phase with the temperature or not, controls the temperature and image display, A micro control unit 194; A status display unit 195 for displaying a temperature and an image forming state under the control of the micro control unit 194; An alarm output unit 196 for generating an alarm upon occurrence of any one of overheating and image formation under the control of the micro control unit 194; An overheat alarm contact output unit 197 for outputting an overheat alarm contact under the control of the micro control unit 194; And an image-formation alarm contact output unit 198 for outputting an image-formation alarm contact under the control of the micro-control unit 194.

The status display section 195 includes a temperature display section 195a for displaying the temperature and an image formation display section 195b for indicating the image formation.

In the epoxy resin molded case according to the preferred embodiment of the present invention, a dry transformer (PT) of the VPI method is built in, and a molding instrument transformer filled with DRY air or a mixed gas as an auxiliary insulating medium is attached Will be described in detail with reference to Figs. 1 to 3. Fig.

First, the mold instrument transformer according to the present invention includes the upper case 141, the lower case 142, and the VPI dry type transformer 130 (including the instrument current transformer 110 and the instrument transformer 120) And make them. At this time, it is preferable that the upper case 141 is integrally molded with an epoxy resin to mount a mounting groove or a mounting structure for mounting the current transformer 110 for a meter. It is preferable that the lower case 142 is integrally formed with an epoxy resin so that the mounting groove or mounting structure for mounting the instrument transformer 142 is integrally formed. Thereafter, the instrument current transformer 110 is seated and fixed at the mounting groove or the mounting structure of the upper case 141, and the instrument transformer 120 is fixed to the mounting groove or mounting structure position of the lower case 142 And then fix it. An upper case 1410 equipped with a current transformer 110 and a lower case 142 equipped with a transformer 120 for a meter are connected to each other using an O-ring, And the lower case 142 are fastened together. At this time, airtightness of the case 140 made up of the upper case 141 and the lower case 142 is achieved by the O-ring.

As described above, according to the present invention, an upper case and a lower case are separately manufactured using an epoxy resin, a separate current transformer manufactured in the upper case is incorporated, a separately manufactured transformer is built in the lower case, An O-ring is added between the lower case, and then the upper case and the lower case are fastened with a fastening screw to produce a mold-type instrument-type transformer. At this time, the transformer and the current transformer embedded in the case and the case are spaced apart from the inside of the case to form a space. Here, the instrumental current transformer and the instrumental transformer are realized by the VPI transformer. The instrumental current transformer 110 is implemented as a high voltage transformer 111 and a low voltage transformer 112 and a core 113 as a current transformer for realizing a transformer of a conventional VPI method and a transformer 120 for a meter Winding 121 and a low-voltage winding 122 and a core 123. In Fig. And the high-voltage winding 121 is implemented as a VPI winding.

Therefore, since the transformer built in the upper case and the lower case is a VPI transformer, optimal insulation is achieved without using a separate insulating member. Typically, VPI transformers use varnish under high vacuum and high pressure conditions using high temperature insulators, and thus are superior in reliability, flame retardancy, short-circuit mechanical strength, and electrical and mechanical properties.

In particular, since the VPI transformer is not molded by the solid resin, the VPI transformer is easy to repair and can be manufactured in the form and size of a free winding. Since there is no solid resin insulator, cracks do not occur, size and weight can be reduced compared to the same kVA capacity, and partial discharge can be prevented. In addition, by using insulated paper and high temperature resin as insulating material and using insulated coil in high vacuum and high pressure state, it has excellent insulation strength improvement and does not decrease moisture and ozone insulation performance for a long time, .

The epoxy case 140 having the built-in VPI transformer is simply coupled with the upper case 141 and the lower case 142 through an O-ring and screwed together to produce a mold instrument transformer. The transformer for mold instrument manufactured in this way has excellent insulation performance without using any other insulating material.

For example, the mold changer according to the present invention manufactured as described above has a maximum temperature rise limit of 220 캜, which is superior to conventional epoxy resin-impregnated mold MOF or inflow mold MOF against heat and excellent in flame retardancy. The insulation paper (aramid insulating paper) used to fabricate the VPI transformer is incinerated and the copper wire is recycled. In this way, the VPI transformer can be recycled. It can be said that it is an affinity product even in terms of the aspect. In addition, the insulation between the conductor and the ground (core) is insulated by an epoxy case, and the high-voltage side winding is manufactured by the VPI method, which has an advantage of excellent insulation and overload performance. In addition, by forming a space between the case of the epoxy resin and the VPI transformer, it is possible to eliminate the interference between the dissimilar materials having different expansion coefficients, thereby preventing the occurrence of cracks. Since the epoxy resin case and the VPI transformer are manufactured separately and then mounted inside the case, there is no risk of bubbles or cracks between the mold release material formed in the process of integrally molding, and thus, it is stable to partial discharge.

However, in order to further improve the insulation performance, the upper case and the lower case are fastened to each other, and then the auxiliary case is connected to the auxiliary case through the valve 160. In this case, Fill the filler. It is preferable that the auxiliary filler material is dry air (dry air) or a mixed gas.

Since the primary terminal K to which the high voltage is inputted according to the present invention and the secondary terminal L to which the changed voltage is outputted are also molded inside the upper case 141, .

Further, the transformer for a mold instrument according to the present invention can perform temperature detection and image formation detection for self diagnosis, analyzes the detected temperature and image formation state, displays it when overheating or image formation, and generates an alarm, It is possible to recognize the overheated state of the instrumental transformer or the phase-laden state easily from the outside.

For example, a temperature detection sensor 171 for detecting the temperature and an image formation voltage detection sensor 172 for detecting the image formation are provided in the vicinity of the instrumental transformer 120 provided inside the case 140, And the output is connected to the control device 190 using the connector 190 which is a terminal terminal. Here, the temperature detection sensor 171 should have high thermal conductivity and insulation, and should be manufactured so that it can be easily installed on the conductor. The measurement temperature should be set at 0 ℃ ~ 150 ℃ and no deformation should be caused by overheating up to 150 ℃. Shock and bending from outside. It is preferable to be protected by a tube of insulation performance and flame-retardant property so as to be protected from moisture and the like.

The temperature and the imaging voltage detected from each sensor are input to the signal input 191 of the controller 190 through the connector 180. The signal input unit 191 transmits a detection signal input to each terminal to the amplifying unit 193 at the subsequent stage through an output channel. At this time, the power control unit 192 appropriately controls the power output from the image forming voltage input terminal, and supplies the driving power to the micro control unit 194 and other parts requiring power.

The amplification unit 193 amplifies the signal input to each channel to a predetermined level according to a predetermined degree of amplification and transmits the amplified signal to the micro control unit 194. Here, since the temperature detection signal or the imaging voltage detection voltage is actually a small signal, it is preferable that the temperature detection signal or the imaging voltage detection voltage is amplified to a signal processable level and provided to the micro control unit 194.

The microcontroller 194 controls the input temperature detection value to be displayed and simultaneously controls the imaging state to display the imaging state information.

The temperature display portion 195a of the status display portion 195 displays the temperature. At this time, it is preferable to display the temperature display method using an apparatus such as FND. Therefore, the manager can easily recognize the temperature of the instrumental transformer from the outside.

In addition, the microcontroller 194 compares the detected temperature with a predetermined reference temperature to determine whether the detected temperature is in an overheated state. Here, it is preferable that the reference temperature for judging whether or not an overheated state is properly set by experiment. As a result of the analysis of the temperature state, only the detected temperature is displayed if there is no overheating. Otherwise, when the overheating occurs, an alarm for overheating is generated through the alarm output unit 196. [ The overheat alarm contact output unit 197 indicates which contact has overheated. According to such an alarm, the administrator can easily recognize which contact point has overheated.

On the other hand, the micro control unit 194 compares the detected imaging voltage with the reference imaging voltage to determine whether or not the imaging has been performed. Here, it is preferable to set the reference imaging voltage for judging whether or not the imaging is performed properly in advance by experiment. A difference occurs in the imaging detection voltage when the actual imaging does not occur and when the imaging occurs, so that the imaging detection voltage can be compared with the reference imaging voltage to determine whether or not the imaging has been made. As a result of the analysis of the imaging state, if an imaging occurs, an imaging warning is given through the alarm output unit 196. As a result, the external administrator can easily recognize the situation where the image is easily visualized. In addition, it is displayed through the imaging warning contact output unit 198 which of the contact points the imaging has occurred.

As described above, according to the present invention, a detection sensor is built in a mold instrument transformer to monitor the temperature rise inside the case, monitor the phase of the main conductor, and display the self-diagnosis status using an alarm device I will. Therefore, the manager can easily recognize the temperature and / or phase state of the transformer for the mold instrument from the outside.

Although the present invention has been described in detail with reference to the above embodiments, it is needless to say that the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention.

INDUSTRIAL APPLICABILITY The present invention is effectively applied to a technique for producing a mold-type instrument transformer.

100: Mold transformer
130: VPI transformer
140: Case
150: O ring
160: Valve
171: Temperature detection sensor
172: image forming voltage detection sensor
180: Connector
190: Control device
191: Signal input section
192:
193:
194: Micro control unit
195: Status display
196: Alarm output section

Claims (8)

A VPI transformer including a meter transformer and a meter transformer formed of a Vacuum Pressure Impregnation (VPI) winding; And
A case formed of an epoxy resin for embedding the VPI transformer;
The case and the VPI transformer are respectively manufactured so as to have a VPI transformer including a current transformer and a VPI-type dry transformer (PT) inside the case formed of an epoxy resin so that insulation can be performed without using a separate insulating material The transformer for the mold instrument is manufactured by filling the inside with the auxiliary insulation medium,
Wherein said case includes a control device for generating an alarm about overheating and image formation at a detected temperature and an image forming voltage, and a mold case instrumentation transformer having a transformer (PT) and a current transformer (CT) embedded in an epoxy resin molded case .
[3] The apparatus of claim 1, wherein the case comprises: an upper case for incorporating the instrument current transformer; (CT) and a current transformer (CT) are embedded in an epoxy resin molded case, characterized in that the upper case and the lower case are combined and then packed by an O-ring. One Mold Case Instrument Transformer
The epoxy resin molded case according to claim 1, wherein the case includes a valve for introducing an auxiliary insulating material, and the auxiliary insulating material uses dry air or a mixed gas. (CT) embedded mold case transformer.
The power unit according to claim 1, wherein the case comprises: a temperature detecting sensor for detecting a temperature; An imaging voltage detecting sensor for detecting an imaging voltage; And a connector for outputting the detected temperature and an image forming voltage value detected by the temperature detecting sensor and the image forming voltage detecting sensor to the outside, wherein the mold comprises a transformer (PT) and a current transformer (CT) Case Instrument Transformer.
delete The apparatus of claim 1, wherein the controller comprises: a signal input unit receiving an output signal of the temperature detection sensor and the image forming voltage detection sensor; A power supply unit for controlling power supplied from the signal input unit; An amplifying unit amplifying each detection signal output from the signal input unit; A micro control unit which is driven by a power supply of the power supply unit and analyzes an output signal of the amplification unit to determine whether the image is in phase with the temperature, controls the temperature and image formation display, and generates an alarm for overheating and image formation; And a state display unit for displaying a temperature and an image-forming state under the control of the micro-control unit, wherein the transformer PT and the current transformer CT are embedded in the epoxy resin molded case.
[7] The apparatus of claim 6, wherein the control unit comprises: an alarm output unit for generating an alarm upon occurrence of any one of overheating and image formation under the control of the micro control unit; An overheat alarm contact output unit for outputting an overheat alarm contact under the control of the micro control unit; Further comprising an image-forming alarm contact output unit for outputting an image-forming alarm contact according to the control of the micro-control unit. The transformer (PT) and the current transformer (CT) are embedded in an epoxy resin molded case.
7. The epoxy resin molded case according to claim 6, wherein the state display portion includes a temperature display portion for displaying a temperature and an image formation display portion for indicating whether or not the image is formed, the mold including a transformer (PT) and a current transformer Case Instrument Transformer.

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