Why the current is outside and the voltage is inside in the loop resistance tester

The reason why the loop resistance tester adopts the measurement method of “current outside and voltage inside” is mainly based on the following considerations:

1. Improve measurement accuracy

① Avoid interference from the internal resistance of the voltage measuring device:

During the measurement process, if the internal resistance of the voltage measuring device (or voltmeter) is not negligible compared with the resistance of the loop to be measured, then the existence of the internal resistance will interfere with the measurement result and cause measurement error.

Setting the voltage measurement point inside the tester can minimize this interference, because the voltage measurement circuit inside the tester is specially designed, and the impact of its internal resistance on the measurement result is minimized.

② Reduce external interference:

External electromagnetic fields, temperature changes and other factors may affect voltage measurement.

Setting the voltage measurement point inside the tester can more effectively shield these external interferences, thereby improving measurement accuracy.

2. Improve safety performance

① Prevent wiring errors:

During the measurement process, if the branch wiring of the circuit to be tested is wrong, it may cause the current to be too large or too small, or even cause a safety accident.

The measurement method of “current outside, voltage inside” can effectively avoid failures and safety accidents caused by wiring errors.

② Protect the measurement circuit:

Setting the voltage measurement point inside the tester can also protect the measurement circuit from abnormal conditions such as external short circuit and overload.

3. Improve measurement speed

① Simplify the internal circuit:

The measurement method of “current outside, voltage inside” can simplify the internal circuit structure of the tester and reduce unnecessary components and connections.

This can not only reduce production costs, but also increase measurement speed, because a simpler circuit structure means faster signal processing and data transmission speed.

② Optimize the measurement process:

By setting the voltage measurement point inside the tester, the measurement process can be optimized and the measurement steps and time can be reduced.

This is especially important for application scenarios that require fast measurement and real-time feedback.

In summary, the measurement method of “current outside, voltage inside” is an effective method adopted by loop resistance testers to improve measurement accuracy, safety performance and measurement speed. This measurement method not only improves the performance and reliability of the tester, but also provides users with a more convenient and efficient measurement experience.

ZC-302E Series Intelligent Loop Resistance Tester is made and contained of advanced high-power switching power supply technology and advanced electronic circuit. It is the dedicated tester for the resistance of high and low switch, cable wire and welding joint. Its current uses national standard GB736 recommended standard DC, can measure the resistance value of being tested object under standard current status. The tester is small dimension, light weight, strong anti-interference, high precision, easy operation and perfect function protection and so on.

Kvtester Electronics Technology Co.,Ltd. is a high-tech enterprise specializing in power testing, testing, research and development, production, and sales of testing equipment. It has been engaged in the electrical testing industry for many years, and its products are of high quality. We welcome customers to come and purchase. Service hotline: 0086-27-81778799, to learn more, visit the official website: www.kvtester.com