Loop-powered or "self-powered." The 88-PRO LCD process meter may be connected directly to a 4-20 mA, 10-50 mA or 1-5 mA current loop, with no need for additional power to the meter. This "self-powered" LCD process meter is powered directly by the current loop, developing a maximum voltage drop of 2.5 V.
Readout in engineering units. By accepting 4-20 mA, 10-50 mA or 1-5 mA process signals, the 88-PRO is compatible with a large number of industrial transducers and transmitters to display process variables such as temperature, pressure, flow, weight, pH, humidity etc. Zero and span are screwdriver adjustable for direct readout in engineering units. There is an INVERT facility, so that an increasing input signal gives a reducing display, for example, 4-20 mA = 100.0 to 0.0. The 88-PRO also provides two jumper-selectable dummy right-hand zero to extend the maximum reading from the default of ±1999 to ±19990 or ±199900. This feature allows the display of large numbers, such as the weight of a truck in pounds. It also useful when the cost of a 4½ or 5½ digit meter would be too high
Easy to install and set up. The 88-PRO fits in a standard 1/8 DIN panel cutout and only requires 93 mm (3.66") behind the panel. This is less than for most process meters. There are only two signal connections: signal in and signal out. These are made via a detachable screw terminal connector. All range-selection jumpers as well as the meter's zero and span adjustments are from the rear of the meter, avoiding the need to open the case.
Attractive and easy to read. The facia of the 88-PRO is attractively styled. The simple bezel will complement your panel design. The lens protects all legends and markings, so repeated wipe-downs won't damage the lettering or display clarity. High contrast LCDs make these meters suitable for use in bright environments. The digits measure a full 12.7 mm (0.50").
An application example. The 88-PRO loop-powered process meter is in series with 12-30 Vdc power to a two-wire 4-20 mA pressure transmitter, which measures the pressure at the bottom of a straight-sided tank. The meter's wide scaling capabilities allow it to be adjusted to display the volume of the tank. If necessary, one or two dummy right hand zeros can be selected to display values up to 199900.
|Range||4-20 mA||10-50 mA||1-5 mA|
|Effective resistance||125 Ω||50 Ω||500 Ω|
|Maximum voltage drop||2.5 V||2.5 V||2.5 V|
|Display range||±1999, ±19990, ±199900 (jumper-selectable)|
|Display height||12.7 mm (0.50")|
|Display type||High-contrast LCD|
|Decimal point selection||Push-on jumpers|
|Display update rate||3 / sec|
|Open circuit response||Display blanks|
|Decimal point selection||Push-on jumpers behind front panel|
|Accuracy||±0.1% of reading ±1 count|
|Resolution, max.||1 part in 2000|
|Calibration method||Zero & span potentiometers|
|CMRR||65 dB, 0-450 Hz|
|Linear ranges||3-21 mA, 8-52 mA, 0.8-6 mA|
|A-D conversion||Dual slope integration|
|Integration period||100 ms|
|Power||Derived from current loop with 2.5 V max drop|
|Bezel dimensions||48 x 96 mm (1.89" x 3.78"), H x W|
|Panel cutout||45 x 92 mm (1.77" x 3.62"), H x W|
|Depth behind panel||93 mm (3.66") including connector|
|Width behind panel||98 mm (3.86") max.|
|Case material||Polycarbonate, UL rating 94V-0|
|Weight||100 g (3.5 oz)|
|Electrical connections||Detachable screw terminal connector|
|Operating temperature||-10°C to 50°C (14°F to 122°F)|
|Humidity||-20°RH at 50°C (122°F), non-condensing|