The DMS-40LCD-4/20S’s ultra-low 2.9V typical loop-drop (190-Ohm burden) makes it ideal for use in 4-20mA process monitoring applications which have two or more series connected loop-monitoring devices. The low loop-burden means it can be used in current loops that are powered from supply voltages as low as +8Vdc! The DMS-40LCD-4/20S is self-powered; all required operating power is derived directly from the current loop itself. It requires no separate dc power supply or special grounding considerations and can be connected ANYWHERE in the loop!

The DMS-40LCD-4/20Ss input, span, and offset circuits all employ super-stable, ±0.5 thin-film chip resistors. Long-term stability and accuracy are assured by driving these tight-tolerance resistors with an ultra-stable, ±0.2 band-gap voltage reference. Unlike many competitor’s designs, the two precision 20-turn span and zero adjust potentiometers do not interact with one another. Its full-size, 0.40 (10.0mm) high-contrast 4½ digit LCD display offers 19,999 counts of resolution and can be read in virtually any lighting condition—including full sunlight!

All range-change and decimal point selections are made by configuring two gold-plated, vibration-resistant, six-position DIP switches. The two connections to the current loop are made via a reliable, screw-type terminal block. To further enhance reliability, the design features 100 soldered connections—no troublesome zebra/elastomercic connectors are used. All these outstanding features make the DMS-40LCD-4/20S the highest quality, most rugged, 4½ digit, LCD-display process monitor available.

FEATURES

■ Loop-powered, no power supply required!

■ 2.9V typical loop-drop; 190-Ohm (max.) loop impedance

■ Dip-switch-selectable range, offset, and decimal points

■ Hundreds of different input/readout combinations

■ Non-interacting gain (span) and offset (zero) 20-turn potentiometers

■ Large, 0.40 (10.0mm) high, sunlight-viewable LCD digits

■ Miniature size: 2.17 x 0.92 x 0.90 (55mm x 23mm x 23mm)

■ Vibration-resistant package; reliable screw terminal connections

■ 100 soldered connections