Retractable test leads are essential for testing circuits in cars, trucks, trailers, boats, equipments and more. Things like trailer taillight troubleshooting, electrical problems from one end of the vehicle to the other, they're of great helpful in performing electrical work on manufacturing equipments or anything larger than a multimeter lead can achieve. You can even use it for bench tests on random bulbs, grounding, switches, and more! Some products have high strength magnetic reels that can be attached to cars, lift arms or even glued to the body. Go ahead and use it to diagnose the electronic elf in your jeep.
We Provideretractable test leads . If you are interested in retractable test leads. Welcome to leave a message!
The Kelvin method for measuring resistance is also called the four-wire method for measuring resistance. It is possible to avoid the influence of the cable resistance on the test results during the measurement, but two additional Kelvin detection wires are required.
In the traditional test method, the current loop and the test loop are the same loop. The current in the loop flows through the cable resistance to produce a voltage drop, which affects the test results.
The Kelvin method measures resistance by separating the current loop from the test loop through four wires and two loops. The current flowing through the test loop is very small, so in the test loop, the voltage drop on the cable resistance can be ignored, which can be accurately measured.
We Provide test leads with alligator clips . If you are interested in Test leads with alligator clips Welcome to leave a message!
The structure of radio frequency cables is diversified and can be classified in different ways.
1. Cable structure classification
1) coaxial radio frequency cable
Coaxial RF cable is the most common structural mode. When the inner and outer conductors are in a concentric position, the electromagnetic energy is limited to the medium propagation between the inner and outer conductors, so it has significant advantages, that is, less weakening, high shielding performance, use frequency bandwidth and performance stability. Usually used to transfer RF energy from 500 kHz to 18KHz.
At present, there are two types of common RF coaxial cables: 50Ω and 75Ω RF coaxial cables. The characteristic impedance 75Ω RF coaxial cable is usually used in CATV network, so it is called COTV cable, and the transmission bandwidth is up to 1GHz. The current CATV cable is currently being transferred to 750MHz.
2) Symmetrical RF cable
The symmetrical RF cable track has an open electromagnetic field, and due to the high frequency of the radiated electromagnetic energy, the attenuation is increased, and the shielding is poor, and the influence of atmospheric conditions is usually rarely used. Symmetrical RF cables are mainly used for low radio frequency or symmetrical feeding.
3) spiral radio frequency cable
The conductor in a coaxial or symmetrical cable can sometimes be a spiral coil to increase the inductance of the cable, thereby increasing the wave impedance and transmission time of the cable. The former is a high-resistance cable, and the latter is used for a delay cable. If the spiral coils have different winding densities in the length direction, the cable can be varistorized.
2. Classification of Insulation Forms
1)physical insulated cables
All physical high-frequency dielectrics are filled between the inner and outer conductors of this kind of cable, and most flexible coaxial radio frequency cables use this form of insulation.
2)air insulated cable
In the cable insulation, except for a part of the solid medium that supports the inner and outer conductors, the rest is basically air. The structural feature of one conductor to another without passing through the mi
Electricians who want to conduct dielectric loss tests on power transformers, relays, capacitors, arresters, etc. need to use an anti-interference dielectric loss tester. As a relatively conventional high-voltage power test equipment, this equipment has high voltage levels and reliable accuracy. And other advantages, but there are still many problems that need to be paid attention to in the process of use, so what are the problems that should be paid attention to when using the anti-interference dielectric loss tester?
1. Ground the instrument reliably to ensure that the shell of the instrument is at ground potential.
2. For positive wiring: insert the high-voltage cable plug into the HV socket of the instrument, clamp the black alligator clip at one end to the high-end lead of the tested product, and hang the red alligator clip in the air. Insert the Cx low-voltage cable into the Cx socket, the red clip at the other end clamps the low end or the end screen of the test sample, and the black clip is suspended or connected to the shielding device.
3. When reverse wiring: insert the high-voltage cable plug into the HV socket of the instrument, clamp the red alligator clip at one end to the high-end lead of the tested product, and hang the black clip in the air or connect to the shielding device. The Cx socket is not used.
4. Comply with the requirements of "Safety Work Regulations for High Voltage Tests".
5. The high-pressure test must be attended by more than two staff members, with one operating and one supervising.
6. After the wiring is completed, one person is responsible for the inspection.
7. After the test, turn off the power switch. It is strictly forbidden to disassemble or assemble the high-voltage cable with power on!
8. If the instrument is abnormal, turn off the power switch and wait for about one minute to check again.
9. After the measurement is completed, the power switch must be turned off, and the wires will be removed after waiting for about one minute.