We produce an electronic product, the output switch signal and current signal (1-5mA), requires a communication distance of 2000m, do not want to buy that long line to test, there is no way to simulate the 2000m cable to test it? I heard that a series resistance (resistance is 2000m cable resistance) to test, the resistance is how much ah? The cable should be a 4-wire 1-square cable. More
According to the provisions is not, but sometimes the space is not enough to set aside the consultation with the supervision of the next!
According to the provisions of the water pipe should be in the design of the bridge below the design of the principle is the same ah you did not install according to the design of the walk? Or the design of the time is so designed, ask the owner if you are responsible for the installation is not so much how they say how you press chant
Can not, if the water pipe installed in the cable above the bridge if the leakage may affect the normal operation of the cable, or even short-circuit accidents, there are security risks! Fire is required.