JPH09163585A - Leak detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the wiring work by inserting two fuses, provided for a pair of feeder lines while being grasped by a fuse holder at the opposite ends thereof, removably into a zero-phase current transformer and holding the zero-phase current transformer by means of the fuses. SOLUTION: A zero-phase current transformer 1 comprises a flat coil and fitted with a synthetic resin spacer 11 to the annular inside thereof. The spacer 11 is provided with two parallel through holes 12 each inserted with a glass tube fuse 2. The glass tube fuse 2 is grasped by a fuse holder 31 secured onto a board 3 and inserted into a feeder line. The board 3 is provided with a window 32 which does not interfere with the zero-phase current transformer 1. Since the fuse serves as the feeder line passing through the zero-phase current transformer, wiring through the zero-phase current transformer can be facilitated and the labor required for assembling zero-phase current transformer can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION Leakage detection for detecting occurrence of leakage from electromotive force induced in a zero-phase current transformer by inserting a pair of power supply lines into a zero-phase current transformer composed of an annular coil. Regarding vessels.

[0002]

2. Description of the Related Art Electric power from a power supply is supplied to a device through a pair of power supply lines. If no leakage occurs in the equipment, the currents flowing through both of the pair of power supply lines have opposite directions but the same current value. However, when a leakage occurs in the equipment, the current value flowing out of the equipment becomes smaller than the current value flowing into the equipment by the leakage current value. When both the pair of power supply lines are inserted into the zero-phase current transformer, the electromotive forces induced in the zero-phase current transformer by the currents flowing through the power supply lines cancel each other out in the state where no leakage occurs. Therefore, electromotive force is not induced in the zero-phase current transformer, but when leakage occurs, the electromotive force induced by the current in both power supply lines is different and the electromotive force is induced in the zero-phase current transformer, causing leakage. Can be detected. Such an earth leakage detector is shown in FIG.
As shown in, the zero-phase current transformer C is attached to the mounting portion CP on the substrate B.
Is attached so that the axis of the zero-phase current transformer C is perpendicular to the substrate B, and the lead wire CL of the zero-phase current transformer C is inserted into the hole CH and soldered. Next, the two electric wires J provided in the middle of the power supply line are inserted into the hole JH so as to straddle the inside and outside of the zero-phase current transformer C and soldered. Electric power is supplied to each component of the equipment not shown.

[0003]

SUMMARY OF THE INVENTION In the above prior art,
Since the two wires must extend inside and outside the zero-phase current transformer, they cannot be wired before mounting the zero-phase current transformer on the board. Therefore, when the two electric wires are wired on the substrate, there is a problem that the wiring work is troublesome because the wires must be wired in a narrow area inside the zero-phase current transformer.

[0004]

The present invention has been made to solve the above problems, and a pair of power supply lines are inserted into a zero-phase current transformer consisting of an annular coil to form a zero-phase current transformer. In a leakage detector that detects the occurrence of leakage from the electromotive force induced in, a fuse holder is held at both ends and two fuses are inserted in each of a pair of power supply lines to form a zero-phase current transformer. It is characterized in that the zero-phase current transformer is held by the fuse so as to be detachably inserted.

Since the fuse is provided in the power supply line, it is possible to detect the occurrence of electrical leakage simply by inserting the fuse into the zero-phase current transformer without additional wiring. Further, since the fuse is gripped by the fuse holder, it is sufficient to set the fuse in the fuse holder with the fuse inserted in the zero-phase current transformer, and the insertion of the fuse in the zero-phase current transformer can be easily performed.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Referring to FIG. 1, reference numeral 1 is a zero-phase current transformer, which is formed of a coil flattened so that its sectional shape is an ellipse or an ellipse. A spacer 11 consisting of is inserted. The spacer 11 is provided with two through holes 12 which are parallel to each other.
A glass tube fuse 2 is inserted into each of the two. The glass tube fuse 2 is a known one in which a linear fuse is enclosed in a glass tube, and internal fuses are connected to metal terminals 21 provided at both ends. The diameter of the hole 12 formed in the spacer 11 is slightly smaller than the outer diameter of the glass tube fuse 2. When the glass tube fuse 2 is inserted into the hole 12, the spacer 11 is elastically deformed. The hole 12 expands, and after insertion, the glass tube fuse 2 is clamped by the elastic force of the spacer 11 and is not displaced with respect to the spacer 11. Further, when the glass tube fuse 2 is replaced, it can be easily pulled out from the through hole 12. The glass tube fuse 2 is gripped by a fuse holder 31 fixed on the substrate 3, and by being gripped by the fuse holder 31, it is provided on a power supply line (not shown). A window hole 32 was provided on the substrate 3 so as not to interfere with the zero-phase current transformer 1.

When the zero-phase current transformer 1 is assembled to the substrate, the two glass tube fuses 2 are inserted into the through holes 12 in advance, and the terminals 21 are held by the fuse holder 31 in this state. Then, the lead wire 13 of the zero-phase current transformer 1 is inserted into the hole 33 formed in the substrate 3 and soldered. This completes the assembly of the zero-phase current transformer 1 to the substrate 3,
When the glass tube fuse 2 is disconnected and replaced, the terminal 21
Is removed from the fuse tube holder 31, the broken glass tube fuse 2 is pulled out, a new glass tube fuse 2 is inserted into the through hole 12, and the fuse holder 31 is allowed to hold it again. During the replacement, the zero-phase current transformer 1 is connected to the lead wire 1.
It remains connected to the substrate 3 by 3 and it is not necessary to remove the zero-phase current transformer 1 itself from the substrate 3.

[0008]

As described above, according to the present invention, the power supply line inserted into the zero-phase current transformer is also used as the fuse, so that the wiring inserted into the zero-phase current transformer can be easily performed. Therefore, the number of man-hours for assembling the zero-phase current transformer can be reduced.

[Brief description of the drawings]

FIG. 1 illustrates a position embodiment of the present invention.

FIG. 2 is a view for explaining an assembled state of a conventional zero-phase current transformer.

[Explanation of symbols]

 1 Zero-phase current transformer 2 Glass tube fuse 3 Substrate 31 Fuse holder

Claims (2)

[Claims] 1. A leakage detector for detecting a leakage from electromotive force induced in a zero-phase current transformer by inserting a pair of power supply lines into a zero-phase current transformer composed of an annular coil. , The two fuses, both ends of which are gripped by the fuse holder and are provided in each of the pair of power supply lines, are detachably inserted into the zero-phase current transformer, and the fuse holds the zero-phase current transformer. Leakage detector characterized by having done. 2. The leakage detector according to claim 1, wherein the fuse is a glass tube fuse in which a fuse wire is enclosed in a glass tube.