Electrical work practice commonly used commonly used formula formula atltech P electrical work practice use opportunely suit low test pen test pen is commonly used one kind of auxiliary and safe appliance electrician.
Used to check V the following conductors or various shell of electrical equipment is charged.
A common low voltage test pen, portable, as long as to master the principle of test pen, some principles known as electrician, flexible skill a lot.
Alternating current (ac) and direct current formula electroprobe evaluation ac/dc, ac dc dark bright, bright neon color photos, communication dc neon light at one end.
Description: told readers a little first, use the low voltage test pen before, must be confirmed on the charged body check-up measure;
Before the test pen is normal may be used.
Discriminant ac, dc, it is best comparison between the 'two', so it is very obvious.
Ends when measuring ac neon glow at the same time, the direct current measurement in the neon only end very shine.
Judge a direct current is negative formula: pencil judgment is negative, observe the neon to talk, front bright is negative, the back-end bright is positive.
Description: the front-end refers to test pen the tip end of the neon, neon back-end refers to one end of the hand, front bright for the cathode, vice is positive.
Test should pay attention to: the supply voltage V and above;
If people with the earth insulation, a hand touch any power supply, the other a hand-held measuring people pen, pencil measured power metal head hit another pole, neon front very shiny, measured the power of the touch is negative;
If neon backend is extremely light, the power of the measured contact is positive, that's according to a dc unidirectional flow and the principle of current flows from negative to positive.
Dc power supply for grounding, is the difference between the cathode grounding formula substation dc coefficient, electroprobe hit not shine;
If light near the pen tip, the anode ground fault;
If the light near the finger end, ground fault in the cathode.
Description: the dc coefficient of power plant and substation, is of insulation, people standing on the ground, with the test pen to touch the positive or negative, neon is should not shine, if light, then dc system grounding phenomenon;
If light near one end of the pen, is the anode grounding;
If light near one end of the fingers, it is negative ground.
Judge with heterogeneous with formula to judge two same line, each hand holding a pen, two feet and ground insulation, two each one to a line, with eyes watching a pen, not bright light for in-phase variations.
Note: this test, and earth must remember feet insulated.
Because our country is mostly a/V, and neutral directly grounding transformer widely adopted, so do the test, between the body and the earth must be insulated, avoid a loop, so as to avoid false judgment;
Test, two bright and light show, not only look at a can.
Judge/V three-phase three-wire system power supply circuit phase line to ground fault formula y connection three-phase line, electroprobe hit two bright, remaining a brightness is weak, the phase conductors have grounding;
If it is almost invisible light, metal earthing fault.
Description: power transformer secondary side is generally take into Y, in three-phase three-wire system of neutral point grounding system, the test pen touch the three phase line, two root, slightly brighter than usual, but on the other less brightness, said this brightness weak phase line grounding phenomenon, but also not too serious;
If the root is very bright, while remaining a nearly invisible light, is this line has a metal ground fault.
The Caledonian gloria Tony cable co. , LTD. , Shanghai office contact person: ms zou email penny @ caledoniancables.
Com company website HTTP / / WWW.
http / / www。
Sohu blog: HTTP / / caledonianpenny.
Com [atltech edited]