TWC 2-Wire Troubleshooting

The most important tool for troubleshooting any 2-Wire decoder system is a milliamp clampmeter, such as the Armada Pro95i. If you do not have a milliamp (mA) clampmeter, contact your local irrigation distributor or order online as Lowes, Home Depot, etc., do not stock milliamp clampmeters. Check out our YouTube channel for several videos from us and our preferred affiliates on 2-Wire troubleshooting.

Testing the 2-Wire Path

When in AUTO or MANUAL mode, the first indication that you might have a short or a fault somewhere on the 2-Wire path is that the line activity indicators (the green and red LEDs on the controller) will flicker, or be not lit at all.

If the TWC NV senses a current leak somewhere, the 2-Wire path will automatically switch to short finding mode, meaning that the LEDs will flicker extremely fast. After a while you'll see an indication that a short occurred. If the leak is severe (current more than 600-650mA), the LEDs will turn off due to the loss of voltage. This is a built-in security mechanism that prevents the controller from short circuiting however, current will still be present on the 2-Wire.

Short-Finding Mode

1. Place the controller in SETUP mode.
2. Use the DOWN arrow button to scroll down to Test and press the ENTER/Yes button.
3. Scroll DOWN to Short Finding and press ENTER.

Display 2-Wire voltage and current

1. Place the controller in SETUP mode.
2. Use the DOWN arrow button to scroll down to Test and press the ENTER/Yes button.
3. Scroll DOWN to Line Survey and press ENTER.