What is a digital indicator and what is it used for
A transmitter sends a current signal to the control system, but the value cannot be seen at the measuring point itself. A digital indicator solves this: it is connected into the 4-20 mA current loop and displays the measured value in engineering units. Operators in the field can see pressure, level or temperature without going to the control room, and service engineers can easily check that the measuring loop is working correctly.
How a loop powered indicator works
The WW-45 and WW-11ALW indicators are connected in series in the transmitter's current loop and draw their power from it, so they need no separate power supply or additional cables. They cause a small voltage drop in the loop (3 V for the WW-11ALW, up to 6 V for the WW-45), which should be taken into account when sizing the transmitter supply. The WW-11N indicator has an external power supply and a voltage drop of up to 6.5 V.
Products in the Fadip range
The WW-45 indicator plugs directly onto the transmitter's DIN EN 175301-803 connector and displays from -999 to 9999, with 0.2% error, at ambient temperatures from 0 to 70 °C and with IP65 protection.
The WW-11ALW indicator has a robust field housing, displays from -99999 to 99999, has a 3 V voltage drop, an operating temperature of -30 to +80 °C and IP66 protection, which makes it suitable for outdoor installation.
The WW-11N indicator with external power supply displays from -999 to 9999, with 0.2% error, an operating temperature of -30 to +50 °C and IP65 protection.
How to choose an indicator
If the transmitter has a DIN EN 175301-803 connector, the simplest solution is the WW-45, which mounts directly onto it. For separate mounting on a wall, pipe or stand and for outdoor conditions, choose the WW-11ALW, and where an external supply is available and an independent indicator is needed, the WW-11N. Also check the total voltage drop in the loop, the ambient temperature and the number of digits required.
Applications
Digital indicators are installed with pressure and level transmitters, temperature transmitters and flowmeters in pumping stations, boiler houses, tanks and process plants, wherever local reading of an electronic measurement is required.
For a quotation, send us the transmitter and connector type, measuring range and display unit, mounting method and ambient conditions. Our technical team will recommend a suitable solution within 24 hours. Contact us.
