Line measuring device fault prompt: 1. The blue, red and green indicators are all on, which means the signal is normal. 2. A single green indicator light lights up, indicating that the ground wire is disconnected or short-circuited. 3. A single blue indicator light lights up, indicating that the positive pole of the signal is disconnected or short-circuited. 4. A single red indicator light lights up, indicating that the negative pole of the signal is disconnected or short-circuited. 5. The red and green indicator lights are on, indicating that the negative pole of the signal and the ground wire are short-circuited. Colour:As Shown Material:Stainless steel Package Contents: 1 * DMX512 line tester Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Scenes to be used: At the performance site or during engineering debugging, if the signal of some lamps is unstable, or the lamps are out of control or unresponsive. You can use this signal line tester to test signals, or you can lines individually. One end of the signal cable is connected to the signal output port of the console, and the other end is connected to the signal tester. Warm reminder: During testing, it must be ensured that the console is connected to the signal. Testing on ports other than signal lines is never allowed. Each lighting console has a different refresh rate, so some testers will cause the LED indicator to flicker when testing signals. (This situation does not affect the normal use of measuring device)