Laurel Laureate Scale Panel Meter

The Laurel Laureate™ Scale Meter is a compact, inexpensive, and extremely accurate digital panel meter with special firmware for weighing applications. It is available with the Laureate load cell or DC signal conditioner board.

The load cell signal conditioner board accepts full-scale ranges of 20, 50, 100, 250 and 500 mV with 4- or 6-wire load cell hookup to display up to 99,999 counts. With 4 wires, the meter operates in a ratiometric mode to eliminate errors due to supply variations. With 6 wires, it also compensates for variations in transducer lead resistance, thereby allowing long cable runs in changing temperature environments. The built-in, isolated excitation supply can power up to four 350-ohm load cells in parallel at 10 Vdc.

The DC signal conditioner board can be jumpered for ratiometric strain gauge voltage ranges ±200 mV, ±2V or ±20V. With this board, a 20 mV strain gauge output can be scaled to display up to 10,000 counts, while a 200 mV output can be scaled to display up to 99,999 counts. Meter accuracy is 0.01% of full scale ± 2 counts.

The Laurel Laureate™ Scale Meter includes a number of features specific to weighing applications. These include a setpoint offset, count-by function, fixed zero, auto-zero, and two tare functions (auto-tare and manual tare).

Easy scale calibration is achieved using a simple two-point calibration method. First, the desired LO IN reading is set to 0, and the desired HI IN reading is set to a desired value. With no weight on the scale, a button is pushed for LO IN. With a known weight on the scale, that button is pushed again for HI IN. The meter then automatically computes scale and offset for readout up to five digits in weight units.

Fast read rates to 60/sec are provided for weigh-in-motion systems, setpoint control, and computer interface. Concurrent Slope (Pat 5,262,780) is a method of analog-to-digital conversion which allows up to 60 conversions per second while integrating the input signal over a full AC line cycle.

An adaptive digital filter can be set for time constants from 17 ms to 9 s, yet responds rapidly to a change in input signal level exceeding a threshold value. The meter can also automatically select the best filter setting for maximum noise rejection and minimum response time. Peak and valley capture are standard.

The Laurel Laureate™ Scale Meter is designed for flexibility. Plug-in isolated analog output, dual setpoint controller, and serial communications boards can upgrade Laureates from a simple monitor to system interface and control. Laureates may be powered from 85-264 Vac or optionally from 12-32 Vac or 10-48 Vdc. They are available with red or green LEDs. The 1/8 DIN case meets NEMA 4X (IP65) specifications from the front when panel mounted. Any setup functions and front panel keys can be locked out for simplified usage and security.