Understanding the "Line Open" Light
If the LINE OPEN LED is flashing the instrument does not have sufficient voltage to emit a constant current, the best solution is to reduce the transmitter electrode contact resistance by wetting the ground around them or planting them deeper. If that fails, the RANGE switch can be moved to the HIGH position. On the Super MiniRes this reduces the output current from 10 milliamps to 1 milliamp but increases the available voltage from about 400 to about 730. On the Standard MiniRes it reduces the current from 5 to 0.5 milliamps
If the LINE OPEN LED is on steady, it indicates a very high resistance in the transmitter cables or electrodes. Check for a loose connection or broken cable.