KR101673476B1 - Ground impedance of the boiler within the various sensors automatically matching apparatus and method - Google Patents

Ground impedance of the boiler within the various sensors automatically matching apparatus and method Download PDF

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Publication number
KR101673476B1
KR101673476B1 KR1020150105850A KR20150105850A KR101673476B1 KR 101673476 B1 KR101673476 B1 KR 101673476B1 KR 1020150105850 A KR1020150105850 A KR 1020150105850A KR 20150105850 A KR20150105850 A KR 20150105850A KR 101673476 B1 KR101673476 B1 KR 101673476B1
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South Korea
Prior art keywords
impedance
sensor
ground
difference
boiler
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KR1020150105850A
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Korean (ko)
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박문영
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린나이코리아 주식회사
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • G01R27/20Measuring earth resistance; Measuring contact resistance, e.g. of earth connections, e.g. plates
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B21/00Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
    • G08B21/18Status alarms
    • G08B21/185Electrical failure alarms

Abstract

The present invention relates to an apparatus and method for automatically matching a ground impedance of various sensors in a boiler and, more particularly, to a system and method for automatically matching a ground impedance of various sensors in a boiler, Detecting an impedance to the sensor; Comparing the detected impedance of each sensor with the inherent impedance of the sensors and calculating the difference; Determining whether an impedance difference calculated by comparing the impedance of each of the detected sensors with the intrinsic impedance of the sensors is out of a predetermined range from the inherent impedance of the sensor; If the difference between the current detection impedance for each sensor and the inherent impedance difference of the corresponding sensor does not exceed the predetermined range, an impedance correction unit having a shape connected in series to each sensor is used to determine the distance between the earth ground and the ground GND And correcting the impedance so that the impedance is equal to the inherent impedance of the sensor.
Therefore, it is possible to overcome the difference in the leakage current of the ground, and it is possible to smoothly and precisely detect various signals through the respective sensors, so that the merchandise of the product itself and the reliability according to the control using each sensor can be greatly improved.

Description

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a ground impedance automatic matching device for various sensors in a boiler,

The present invention relates to an apparatus and method for automatically matching the ground impedance of various sensors in a boiler, and more particularly, to various sensors for sensing various signals through a ground in a boiler (for example, a frame rod (FR) An impedance detection unit and an impedance correction unit are provided in the ground level detection sensor and the ground fault detection sensor to detect the impedance between the earth ground and the ground GND for each sensor in normal operation so that each sensor operates normally A ground impedance automatic matching device for various sensors in a boiler and a method therefor to overcome the difference in the leakage current of the ground through the method of automatically correcting the required impedance to the required one so that the detection through each sensor can be smoothly performed .

Generally, a boiler is used to heat water by using combustion heat and heat generated by burning it using fuel, coal or gas as fuel, or supplying electricity to a heater, and supplying hot water to various heating facilities In the case of a domestic boiler, hot water is supplied to the piping installed on the floor of the room or the like, and is used for supplying hot water through a water pipe or the like.

When the heating mode is operated in the normal heating / hot water boiler, the circulation pump is operated to transfer the heating water, and the heating water is heated in the main heat exchanger and transferred to the heating load (that is, the heating pipe) Heating is done.

In addition, the supply of the hot water blocks the path from the three sides to the heating load side and opens the path to the hot water heat exchanger side to transfer the warm water heated in the main heat exchanger to the hot water heat exchanger side, The hot water can be supplied to the user.

The boiler having such a construction is installed with the capacity of the boiler being determined according to the appropriate level of the place where the heating is required. That is, if there are several rooms requiring heating, the capacity of the boiler is determined so that the heating can be supplied based on the entire room.

In addition, the boiler is provided with a frame rod (FR) for detecting the flame of the burner as an electrical signal, a water level detecting sensor for detecting the water level in the water tank by an electric signal, and a ground fault detecting sensor Various sensors are provided.

Each of these sensors must have an inherent impedance. For example, in the case of a frame load, it should have an impedance of 800 kΩ to 1.5 MΩ, a water level sensor should have an impedance of 390 kΩ to 700 kΩ, Should have an impedance of ~ 10 k ?.

On the other hand, in various boilers, there is a problem that sensing of various sensors using the ground is not smooth due to the leakage amount of the ground current or the problem of the ground resistance.

Conventionally, impedance is measured for various sensors (that is, the impedance between the ground and ground GND is detected for each sensor) according to the field conditions, and impedance matching There is an inconvenience of performing the work directly or performing the grounding work again.

Korean Patent Publication No. 10-1995-0001315 (January 03, 1995) Korean Registered Patent No. 10-1164147 (Jul. 03, 2012)

SUMMARY OF THE INVENTION It is an object of the present invention to provide an impedance detecting unit and an impedance detecting unit for various sensors such as a frame rod (FR) for sensing various signals through a ground in a boiler, a water level detecting sensor, And an impedance between the earth ground and the ground GND for each sensor is detected through the impedance detecting unit when the power supply voltage is supplied or the operation switch is turned & And then corrects each of the sensors to an inherent impedance required for normal operation through the impedance corrector so as to overcome the fine leakage current difference of the ground so that detection of various signals through each sensor is smooth Because it can be done precisely, it depends on the product itself and the control using each sensor And an object of the present invention is to provide an automatic grounding impedance matching device for various sensors in a boiler which can greatly improve reliability and the like.

It is another object of the present invention to provide a method of detecting a difference between an impedance of a predetermined sensor and an impedance of a sensor, It is possible to smoothly repair the boiler in the future, and it is also possible to stop the boiler safely and automatically match the ground impedance of various sensors in the boiler to prevent various components from being damaged due to the impedance failure of the sensor Apparatus and method therefor.

In order to achieve the above object, the present invention provides a boiler having various sensors such as a frame load (FR) sensing various signals through a ground, and various sensors such as a water level detecting sensor and a ground fault detecting sensor, In constructing a ground impedance automatic matching device of various sensors in a boiler for automatic matching, it is necessary to connect between a ground (earth) for the sensor and a ground (GND) for the sensor between the terminals of various sensors connected between the microcomputer and the ground And an impedance detector for detecting the impedance of the microcomputer and transmitting the detected impedance to the microcomputer. The impedance of the sensor is automatically adjusted between the output terminal of the microcomputer and the input terminal of the various sensors to correspond to the output impedance of the microcomputer, And an impedance correction unit is additionally provided.

According to an aspect of the present invention, there is provided a method for controlling a ground impedance of various sensors in a micom of a boiler provided with a frame rod (FR) sensing various signals through a ground, various sensors such as a water level detecting sensor and a ground fault detecting sensor, In the boiler, when the power is supplied to the boiler or when the operation switch is turned "on ", the microcomputer detects the impedance of each sensor Detecting an impedance for each of the sensors through the provided impedance detecting unit; Comparing the detected impedance of each sensor with the inherent impedance of the sensors and calculating the difference; Determining whether the impedance difference calculated by comparing the impedance of each of the detected sensors with the intrinsic impedance of the sensors is out of a predetermined range from the intrinsic impedance of the sensor; If the difference between the current detection impedance for each sensor and the inherent impedance difference of the corresponding sensor does not exceed the predetermined range, an impedance correction unit having a shape connected in series to each sensor is used to determine the distance between the earth ground and the ground GND And correcting the impedance so that the impedance is equal to the inherent impedance of the sensor.

If the microcomputer determines that the difference between the current detection impedance for each sensor and the inherent impedance difference of the sensor is out of a predetermined range, the sensor name and the sensor indicate that an impedance error has occurred in the sensor Is further performed.

In addition, when the current detection impedance of the specific sensor and the inherent impedance difference are out of a predetermined range, the step of stopping all the functional components in the boiler and stopping the combustion operation so that the combustion operation is not performed is further performed.

On the other hand, the predetermined range to be compared with the calculated difference after calculating the current detection impedance for each sensor and the inherent impedance difference of the sensor is set to be ± 20 to 25% from the inherent impedance of the sensors.

As described above, according to the automatic ground impedance matching apparatus and method of the various sensors in the boiler according to the present invention, it is possible to provide a method of automatically matching the ground impedance of various sensors such as a frame rod FR sensing various signals through a ground in a boiler, An impedance detecting unit and an impedance correcting unit are additionally provided to various sensors. When the power supply voltage is supplied or the operation switch is turned "on ", the impedance between the ground ground and the ground (GND) And the difference between the intrinsic impedance of the corresponding sensor and the inherent impedance required for normal operation of each sensor through the impedance corrector is compensated to overcome the fine leakage current difference of the ground, Since the detection of various signals can be carried out smoothly and accurately, And it can greatly improve the reliability and so on according to the control using the respective sensors.

In addition, when the impedance of a predetermined sensor out of the respective sensors is out of the inherent impedance range of the sensor, the difference is found. If the difference is out of a range that can be solved by correction, an impedance error occurs in the sensor name and the corresponding sensor It is possible to smoothly repair the boiler in the future and to prevent the various components from being damaged due to the impedance failure of the sensor by stopping the boiler safely in advance and also to control the boiler using various sensors The reliability according to the invention and the merchantability of the product itself can be greatly improved.

1 is a schematic block diagram of a boiler to which the present invention apparatus is applied;
2 is a flow chart for explaining the method of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

FIG. 1 is a schematic block diagram of a boiler to which the present invention is applied, and FIG. 2 is a flow chart for explaining the method of the present invention.

According to the present invention,

The microcomputer 1 in the boiler provided with the frame load (FR) for sensing various signals through the ground, various sensors (2) such as a water level detecting sensor and a ground fault detecting sensor is automatically matched with the ground impedances of various sensors In constructing a ground impedance automatic matching device for various sensors in a boiler,

An impedance detector for detecting the impedance between the ground and the ground of the sensor for detecting the impedance between the microcomputer and the various sensors connected between the microcomputer and the ground and transmitting the detected impedance to the microcomputer; (3) is installed,

Between the output terminal of the microcomputer 1 and the input terminal of the various sensors 2, the detection impedance Rdet of the corresponding sensor is automatically corrected to correspond to the intrinsic impedance Rref in response to the output signal of the microcomputer 1 And an impedance correcting unit 4 is additionally provided.

In addition,

The microcomputer 1 in the boiler having various sensors 2 such as a frame load (FR) sensing various signals through the ground, a water level detecting sensor and a ground fault detecting sensor detects the ground impedance of various sensors, Rref) of the boiler, the automatic matching method of ground impedance of various sensors in the boiler,

Detecting the impedance Rdet for each sensor through the impedance detection unit 3 provided in each sensor 2 in the microcomputer 1 when power is supplied to the boiler or the operation switch is turned on (S1);

(S2) of comparing the impedance Rdet of each of the detected sensors 2 with the intrinsic impedance Rref of the sensors and calculating the difference therebetween;

It is determined whether the impedance difference calculated by comparing the detected impedance Rdet of each sensor 2 and the intrinsic impedance Rref of the sensors 2 is out of a predetermined range ± X% from the intrinsic impedance Rref of the sensor Step S3;

When the difference between the current detection impedance Rdet for each sensor 2 and the inherent impedance Rref of the sensor does not deviate from the predetermined range (± X%), (S4) of correcting the impedance between the earth ground (GND) of the sensor and the earth ground (GND) of the sensor to be equal to the intrinsic impedance (Rref) of the sensor through the sensor (4).

(± X%) as a result of the microcomputer 1 determining whether the difference between the current detection impedance Rdet for each sensor 2 and the inherent impedance Rref of the sensor is out of a predetermined range ± X% If it is off,

(S5) indicating that an impedance error has occurred in the corresponding sensor name and the corresponding sensor in the display unit (5).

When the difference between the present detection impedance Rdet and the specific impedance Rref of the specific sensor is out of the predetermined range (± X%),

(S6) of shutting off all functional components in the boiler and stopping the combustion operation so as not to perform the combustion operation.

On the other hand, a predetermined range (± X%), which is compared with the calculated difference after calculating the difference between the current detection impedance Rdet for each sensor 2 and the inherent impedance Rref of the sensor,

Is set to ± 20 to 25% from the intrinsic impedance (Rref) of the sensors.

Reference numeral 6 denotes a key input unit, 7 denotes a storage device, and 8 denotes a functional component driving unit.

The operation and effect of the apparatus and method for matching ground impedance of various sensors in the boiler according to the present invention constructed as above will be described as follows.

First, the apparatus of the present invention includes a microcomputer 1 and various sensors (not shown) of components of a known boiler having various sensors 2 such as a frame load (FR) sensing various signals through a ground and a water level detecting sensor and a ground fault detecting sensor, When the initial power supply voltage is supplied to the boiler or the operation switch is turned "on " by providing the impedance detecting unit 3 and the impedance correcting unit 4 between the ground 2 and the ground, The impedance between the earth ground and the ground GND of the sensor 2 is detected to determine a difference between the impedance and the intrinsic impedance of the sensor 2 and then the impedance is corrected through the impedance corrector 4, The main technical components are those that can automatically compensate for the inherent impedance required for operation.

When the microcomputer 1 is in a state of being installed between both terminals of various sensors 2 connected between the microcomputer 1 and the ground, the impedance detecting unit 3 detects the impedance of the ground Detects the impedance between the earth (Earth) and the boiler body ground (GND), and transmits the detected impedance to the microcomputer (1).

The impedance corrector 4 is connected in series between the output terminal of the microcomputer 1 and the input terminals of various sensors 2 and is connected to each sensor 2 through the impedance detector 3. [ The impedance Rdet of the sensor is determined as a characteristic impedance corresponding to the output signal of the microcomputer 1 that outputs a predetermined control signal when the impedance is within a predetermined range, (Rref) in accordance with the automatic correction.

On the other hand, in the method of the present invention, when the power supply voltage is supplied to the boiler or when the user turns on the operation switch, the impedance of each of the various sensors 2 installed in the boiler body in the micom 1 provided in the boiler The current impedance Rdet for each sensor is detected through the detection unit 3 or the like (S1).

Next, the microcomputer 1 compares the impedance Rdet of each sensor 2 detected through the impedance detector 3 with the intrinsic impedance Rref of each sensor, The difference between the impedance Rdet of each of the sensors 2 and the inherent impedance Rref of the corresponding sensors) (S2).

The microcomputer 1 then compares the impedance Rdet of each sensor 2 and the intrinsic impedance Rref of the sensors 2 to calculate a difference in impedance from the intrinsic impedance Rref of the sensors %) (S3).

At this time, the frame load, which is one of the sensors 2 used in the boiler, must have an impedance of 800 k? To 1.5 M? As described in the related art, and the water level sensor must have an impedance of 390 k? In the microcomputer 1, as described above, the impedance Rdet detected by each of the sensors 2 is determined based on the inherent impedance to be possessed when the sensors are normal (X%) from the predetermined range (Rref) (S3).

Here, the predetermined range (± X%) compared with the calculated difference after calculating the difference between the current detection impedance Rdet for each sensor 2 and the inherent impedance Rref of the sensor 2 is determined by considering the sensor characteristics , And it is set in the range of ± 20 to 25% from the intrinsic impedance (Rref) of the sensors according to the present invention.

As a result, it is determined that the difference between the current detection impedance Rdet and the inherent impedance Rref of each sensor 2 in the microcomputer 1 deviates from a predetermined range (± X%). As a result, The microcomputer 1 determines that the difference (Rdet) and the difference of the intrinsic impedance Rref of the corresponding sensor (the impedance in the state where the impedance is higher or lower than the intrinsic impedance) does not deviate from the predetermined range (± X% The impedance between the earth ground and the ground GND of the corresponding sensor is adjusted to be equal to the inherent impedance Rref of the sensor through the impedance corrector 4 having the shape connected to the sensor 2 of the sensor 2 in series. (S4).

That is, if the difference between the impedance Rdet detected by the sensor and the inherent impedance Rref of the sensor is calculated and the difference is within a predetermined range (± X%) than the reference impedance value Rref, the microcomputer 1 A correction operation is performed to increase or decrease the impedance so that the impedance of the sensor becomes equal to the inherent impedance Rref of the corresponding sensor through impedance correction units 4 connected in series to each sensor 2 S4).

Therefore, it is possible to overcome the difference between the leakage currents of the various sensors 2 used in the boiler by the impedance correction (that is, the impedance of each sensor can be automatically matched) ) Can be smoothly and accurately detected, thereby greatly improving the merchandise of the product itself and the reliability of the control using each sensor.

When the microcomputer 1 determines that the difference between the current detection impedance Rdet of each sensor 2 and the inherent impedance Rref of the sensor 2 is out of the predetermined range ± X% , The difference between the current detection impedance Rdet for each sensor 2 and the inherent impedance Rref of the corresponding sensor is excessively large so that it is corrected through the impedance correction unit 4 The microcomputer 1 recognizes that the impedance of the corresponding sensor can not be automatically matched to the inherent impedance and the microcomputer 1 displays the sensor name and the occurrence of an impedance error in the corresponding sensor on the display unit 5 ).

Therefore, the service man who not only receives the user of the boiler but also the failure can accurately check which sensor among the plurality of sensors has failed and smoothly and accurately repair the boiler in a short period of time It is.

In addition, in the present invention, after calculating the difference between the current detection impedance Rdet and the inherent impedance Rref of the specific sensor as described above, if the difference is out of a predetermined range (± X%) with respect to the intrinsic impedance Rref of the sensor When the error message is displayed on the display unit 5 as described above, it is possible to stop the functioning of all the functional parts in the boiler and to prevent the combustion operation from being carried out. (S6).

Accordingly, it is possible not only to prevent damage or breakage of various components in the boiler which may occur when the operation of the boiler is continuously performed while the impedance of the specific sensor is greatly changed due to a large leakage current during operation of the boiler , Reliability according to the control of the boiler using various sensors, and merchantability of the product itself can be greatly improved.

Although the preferred embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Which will be apparent to those skilled in the art.

1: Microcomputer
2: Sensor
3: Impedance detector
4: Impedance correcting unit
5:
6:
7: Storage device
8: Functional part driving part
Rdet: Detection Impedance
Rref: inherent impedance

Claims (5)

A frame load (FR) for sensing various signals through the ground, and grounding of various sensors in the boiler for automatically matching ground impedances to various sensors in a boiler equipped with various sensors such as a water level detecting sensor and a ground fault detecting sensor In constructing the impedance automatic matching apparatus,
An impedance detecting unit is provided between both terminals of various sensors connected between the microcomputer and the ground to detect the impedance between the earth ground and the ground GND for the sensor and transmit the detected impedance to the microcomputer,
And an impedance correction unit is provided between the output terminal of the microcomputer and the input terminals of various sensors for automatically correcting the impedance of the corresponding sensor to correspond to the specific impedance in response to the output signal of the microcomputer. Ground impedance automatic matching device.
The ground impedance of various sensors is detected by a micom of a boiler equipped with a frame load (FR) which senses various signals through the ground and various sensors such as a water level detecting sensor and a ground fault detecting sensor, and is automatically matched to correspond to a unique impedance In constructing a method for automatic matching of ground impedance of various sensors in a boiler,
Detecting an impedance for each sensor through an impedance detecting unit provided in each of the sensors when power is supplied to the boiler or the operation switch is turned "on ";
Comparing the detected impedance of each sensor with the inherent impedance of the sensors and calculating the difference;
Determining whether an impedance difference calculated by comparing the impedance of each of the detected sensors with the intrinsic impedance of the sensors is out of a predetermined range from the inherent impedance of the sensor;
If the difference between the current detection impedance for each sensor and the inherent impedance difference of the corresponding sensor does not exceed the predetermined range, an impedance correction unit having a shape connected in series to each sensor is used to determine the distance between the earth ground and the ground GND And adjusting the impedance so that the impedance is equal to the inherent impedance of the corresponding sensor.
The method of claim 2,
If the microcomputer determines that the difference between the current detection impedance of each sensor and the inherent impedance difference of the sensor is out of the predetermined range,
And displaying a sensor name and an indication of an impedance error in the sensor on the display unit.
The method of claim 3,
When the difference between the present detection impedance and the inherent impedance of the specific sensor is outside the predetermined range,
And stopping the operation of all the functional parts in the boiler and stopping the combustion operation so as not to be performed.
The method according to any one of claims 2 to 4,
The predetermined range, which is compared with the calculated difference,
And the specific impedance of the sensors is set to ± 20 to 25%.
KR1020150105850A 2015-07-27 2015-07-27 Ground impedance of the boiler within the various sensors automatically matching apparatus and method KR101673476B1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20210112465A (en) * 2020-03-05 2021-09-15 아머스 주식회사 Capacitive type level sensor capable of self diagnosis

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR950001315A (en) 1993-06-17 1995-01-03 윤갑구 Transient Impedance Measurement Device
KR20050007434A (en) * 2002-02-19 2005-01-18 타이코 플로우 컨트롤 인코포레이티드 Method and apparatus for circuit fault detection with boiler water level detection system
KR101164147B1 (en) 2011-07-15 2012-07-11 한국 전기안전공사 Ground impedance calibration device
JP4996992B2 (en) * 2007-06-20 2012-08-08 日置電機株式会社 Impedance measuring device
JP5357091B2 (en) * 2010-03-23 2013-12-04 株式会社ダイヘン High frequency measuring device and calibration method of high frequency measuring device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR950001315A (en) 1993-06-17 1995-01-03 윤갑구 Transient Impedance Measurement Device
KR20050007434A (en) * 2002-02-19 2005-01-18 타이코 플로우 컨트롤 인코포레이티드 Method and apparatus for circuit fault detection with boiler water level detection system
JP4996992B2 (en) * 2007-06-20 2012-08-08 日置電機株式会社 Impedance measuring device
JP5357091B2 (en) * 2010-03-23 2013-12-04 株式会社ダイヘン High frequency measuring device and calibration method of high frequency measuring device
KR101164147B1 (en) 2011-07-15 2012-07-11 한국 전기안전공사 Ground impedance calibration device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20210112465A (en) * 2020-03-05 2021-09-15 아머스 주식회사 Capacitive type level sensor capable of self diagnosis
KR102311279B1 (en) * 2020-03-05 2021-10-13 아머스 주식회사 Capacitive type level sensor capable of self diagnosis

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