Frquently Asked Questions

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Ultrasonic

Can I use the transmitter in a standpipe application?

Yes. They can be mounted in a standpipe to filter out turbulence and surface foam. The pipe could have diameters of between 25 mm (1") and 152 mm (6").

What is Relay output?

A Relay output is a small mechanical dry contact switch. The sensors internal circuit tells the relay to energise or de-energise when a change to the input has occurred. The relay can be wired either normally open or normally closed by reversing the polarity of the circuit.

What is the difference between the Relay and the FET?

The Relay is a mechanical switch. A tiny arm moves inside the relay providing either an open or closed contact. A FET switch (Field Effect Transistor) is a solid state switch, no moving parts. The FET switch is designed for interfacing to a PLC. The maximum rating for the FET is 36 VDC @ 100mA. The Relay is designed for interfacing directly to a device such as a light buzzer or another relay. The maximum rating for the Relay is 60 VDC/VAC @ 1A.

What is the difference between the three wire and two wire UCL-200 series units?

The UCL-200 series three-wire ultrasonic transmitters have a greater measurement span (7460 mm & 12190 mm) than the two-wire ultrasonic units (452 mm).

What size cable should I use to wire a two wire level transmitter back to a relay controller?

Generally, 18-gauge cable should be sufficient for distances of up to 304.8 meters (1000 feet). Shielded cable is recommended, especially in areas with high amounts of electrical noise. The entire loop resistance should not exceed 900 ohms.