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Laureate™ Load Cell & Microvolt
Panel Meter
20 mV - 500 mV full-scale ranges, 4- or 6-wire
connection

Features
- 20, 50, 100, 250 & 500 mV
ranges.
- 5-digit resolution with span from
0 to ± 99,999
- Zero from -99,999 to +99,999
- Selectable fixed
right-hand zero.
- Isolated 10 Vdc supply to power
up to four 350-ohm load cells in parallel.
- 4- or 6-wire hookup
to avoid lead resistance effects.
- Ratiometric operation
to cancel
variations in excitation supply.
- Up to 60 conversions per second.
- Peak value display
(standard).
- Auto-tare with tare value stored
in memory.
- AC or DC powered.
- Green or red display
-
NEMA 4X, 1/8 DIN case
-
Dual relay option
-
Analog output option
-
Serial communication options
- Low voltage AC & DC power
- Certified to UL 61010C-1 (UL mark), EN 61010-1 (CE mark),
and RoHS.
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Description

The
Laureate load cell and microvoltmeter is a high-sensitivity monitor and controller
for use with load cells, strain gauges and microvolt input signals where high accuracy and
stability are required.
Usage as a DC microvoltmeter provides
sensitivity down to 20 mV full scale with 1 µV resolution. With a digital multiplier
of five, 99,999 counts can be displayed with a sensitivity of 0.2 µV per count. A moving
average filter with a time constant of 1.2 sec or greater should then be selected.
Usage as a load cell meter allows six-wire
hookup and scaling for direct readout in engineering units, such as pounds, kilograms or
PSI. Scaling can be via front panel pushbuttons or a computer. Zero may be set from
-99,999 to +99,999. Range may be scaled from 0 to ±99,999. Digital scaling and
calibration eliminate drift caused by potentiometers in non-microcomputer based meters.
Built-in Excitation
An isolated 10 Vdc
excitation supply can provide up to 120 mA of current to power up to four 350-ohm load
cells in parallel. The meter operates in a ratiometric mode to eliminate errors due to
supply variations. When excitation sense inputs are used in 6-wire connection, the meter
compensates for variation in resistance of the transducer leads, thereby allowing long
cable runs.
Fast Read Rate plus Peak Capture
All Laureate meters use
Concurrent Slope (Pat 5,262,780) analog-to-digital conversion, which allows up to 60
conversions per second, while integrating the signal over a full power cycle. High read
rate is ideal for peak value capture and for real-time computer interface and control. Peak capture is standard.
Selectable Signal Filtering
The displayed readings
and the data outputs can be separately selected to be either unfiltered or filtered.
- An unfiltered
selection updates after each conversion for fastest response, up to 60/sec, while
integrating the input signal over a full power cycle. Fast read rate provides true peak
readings and aids in control applications.
- A batch average
filter selection averages each 16 conversions for an update every 1/4 sec.
- An adaptive moving
average filter selection provides a choice of 8 time constants from 80 ms to 9.6
s. When a significant change in signal level occurs, the filter adapts by briefly
switching to the shortest time to follow the change, then reverts back to its selected
time constant. Another choice is Auto, which provides an automatic time constant selection
based on the signal noise characteristics.
Easy Scaling
All Laureate DC, process
and load cell meters allow easy setting of scale and offset by either of two methods.
- With the coordinate
reading method, the meter reads the high and low signal values, and the user
enters the desired high an low reading values. The meter then calculates the span
multiplier and offset. This method is ideal if an external calibration reference is
available.
- With the manual
coordinate method, the user enters the high and low input values in Volts plus
the desired high and low reading values. This method is suitable if no external
calibration reference is available.
Auto-tare
For weighing
applications, auto-tare is standard. Auto-tare can set the displayed value to zero to
subtract the weight of an empty container. Auto-tare may be controlled by an external
pushbutton contact closure or logic signal through an input on the power supply connector.
The tare value is stored in memory. Additional capabilities for weighing
applications are provided by the Laureate weight / scale meter, as described in a separate
web page.
Other Features
& Options
Plug-in isolated
analog output, dual setpoint controller,
and
RS232/485 serial data I/O boards can upgrade the Laureate from a
stand-alone monitor to system interface and control. The
1/8 DIN case of Laureate meters and
counters meets NEMA 4X (IP-65) standards from the front for high
pressure wash-down when panel mounted.
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Specifications
DC Microvoltmeter Inputs
Input
Range
mV |
Resolution |
Input
Resistance |
Error
at 25°C |
±20.000
±50.000
±100.00
±250.00
±500.00 |
1
µV
1 µV
10 µV
10 µV
10 µV |
1 GOhm |
0.01% FS
±2 counts |
Load Cell Inputs
Full-Scale
Input, mV |
Zero
Adjust |
Span
Adjust |
Input Resistance |
Error
at 25°C |
±20.000
±50.000
±100.00
±250.00
±500.00 |
-99,999
to
+99,999 |
0 to
±99,999 |
1 GOhm |
0.01% FS
±2 counts |
DC Microvolts
& Load Cell
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Accuracy |
Span Tempco
Zero Tempco |
0.0015% of reading/°C
0.1 µV/°C |
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Noise Rejection |
CMR, DC to 60 Hz
NMR at 50/60 Hz |
130 dB
90 dB with min filtering |
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A-to-D Conversion |
Technique
A-to-D Rate
Output Update
Display Update |
Concurrent Slope™ (Pat 5,262,780)
60/s at 60 Hz, 50/s at 50 Hz
56/s at 60 Hz, 47/s at 50 Hz
3.5/s at 60 Hz, 3/s at 50 Hz |
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Display |
Readout
Range
Indicators |
5 LED digits, 7-segment, 14.2 mm (.56"), red or green.
-99999 to 99999 or -99990 to 99990
(count by 10 with rounding)
Minus sign, 2 red LED lamps |
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Power |
Voltage, standard
Voltage, optional
Frequency
Power Isolation |
95-240 Vac ±10% or 90-300 Vdc
12-30 Vac or 10-48 Vdc
DC or 47-63 Hz
250V rms working, 2.3 kV rms per 1 min test. |
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Excitation Output |
5 Vdc
10 Vdc
24 Vdc
Output Isolation |
5 Vdc ±5%, 100 mA
10 Vdc ±5%, 120 mA
24 Vdc ±5%, 50 mA
50 Vdc to meter ground |
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Analog Output (optional) |
Output
levels
Compliance
Scaling
Resolution
Isolation |
0-10V,
0-20 mA, 4-20 mA (jumper selectable)
2 mA at 10V (5 kOhm load), 12V at 20 mA (0-60 ohm load)
Zero and full scale adjustable from -99999 to +99999
12 bits (0.025% of full scale)
250V rms working, 2.3 kV rms per 1 min test |
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Dual Contact Relay Outputs (optional) |
Relay
Type
Load Rating
Isolation |
Form C
8A at 250 Vac or 24 Vdc
250V rms working, 2.3 kV rms per 1 min test |
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Dual Solid State Relay Outputs (optional) |
Relay Type
Load Rating
Isolation |
SPST, normally open,
Form A
120 mA at 130 Vac or 170 Vdc, 28 ohms series resistance.
250V rms working, 2.3 kV rms per 1 min test |
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Serial Data I/O (optional) |
Board Selections
Protocols
Data Rates
Digital Addresses
Isolation |
RS232, RS485, Modbus RS485
Modbus RTU, Modbus ASCII, simpler Laurel ASCII
300 to 19200 bps
247 (Modbus), 31 (Laurel ASCII),
250V rms working, 2.3 kV rms per 1 min test |
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Signal Connections |
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Environmental |
Operating
Temperature
Storage Temperature
Relative Humidity
Protection |
0°C to
60°C
-40°C to 85°C
95% at 40°C, non-condensing
NEMA-4X (IP-65) when panel mounted |
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Load Cell
Meter Connections
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In 4-wire connection, the excitation and
sense lines are tied together. The meter can make ratiometric corrections for supply
voltage variations, but not compensate for variations in lead resistance. This connection
is often used with short cable runs. |
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In 6-wire connection, the sense lines are
separate from the excitation lines, thereby eliminating effects due to variations in lead
resistance. This allows long cable runs in outdoor environments with temperature extremes. |
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For large scales, up to four 350 ohm load
cells can be powered by a single Laureate, whose excitation output is rated 120 mA at 10
V. The excitation and sense points of the four bridges are connected in parallel through a
summing box. |

Sample
Load Cell Meter Applications
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Auto-Tare To read the net weight of an object, the empty container is first weighed, and an
external button is pushed to zero out the display. The meter will then read net weight
when an object is added to the empty container. The tare value is stored in memory for
subsequent readings. |
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Determining Volume Using Load Cells An easy way to determine volume of an irregularly shaped tank with
no need for linearizing is to weigh the tank using load cells. The meter will automatic-
ally tare out the weight of the empty tank and then scale the load cell signals to units
of volume, such as gallons. |
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Peak Capture for Tensile Strength of
Wire Peak readings are automatically
captured at rates up to 60 per second, while the display updates at a legible 3.5 per
second. The peak reading can be recalled at the push of a button or be always displayed.
It can also be transmitted to a computer via RS-232 or RS-485. |

Ordering
Guide
Laureate™ Load Cell & Microvolt Panel Meters
Create a model
number in this format: L10010WM. This example calls out a Laureate
panel meter with a Standard Main Board with green LEDs, 95-240 Vac ±10% &
90-300 Vdc power, no setpoint output, 0-20 mA & 0-10 V analog outputs, no
digital interface, and a load cell signal conditioner with default scaling
set for 0-20 mV = 0-100.00. Includes plug-in screw terminals.
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DPM
Type |
L Digital Panel Meter. |
$220 |
Main
Board |
1 Standard Main Board, Green LEDs.
2 Standard Main Board, Red LEDs.
3 Extended Main Board, Green LEDs.
4 Extended Main Board, Red LEDs. |
NC
NC
$40
$40 |
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Note: Extended capability is
only required for custom curve linearization or for display of time rate
of change, such as flow rate from changing tank weight. |
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Power |
0 Isolated 95-240 Vac ±10% & 90-300 Vdc
1 Isolated 12-30 Vac & 10-48 Vdc. |
NC
$30 |
Setpoint
Output |
0 None.
1 Dual 8A Contact Relays.
2 Isolated Dual Solid State Relays. |
NC
$80
$55 |
Analog
Output |
0 None.
1 Isolated 0-20 mA & 0-10 V. |
NC
$90 |
Digital Interface |
0 None.
1 Isolated RS-232.
2 Isolated RS-485.
4 Isolated Modbus RS-485. |
NC $60 $80 $90 |
Signal
Input |
Load Cells (6-wire ratio)
WM Default Scaling. 0-20 mV = 0-100.00.
WM1 Custom Scaling.
In the write-in field of your order, specify min input, min reading; max
input, max reading. Full-scale input is 20-500 mV. Excitation is 10 V for
up to four 350-ohm load cells. |
$55 |
Add-on
Options |
EB
BL
CBL01
CBL02
IPC
BOX1
BOX2 |
Extra bight red LED display
Blank lens without button pads
RJ11-to-DB9 cable
USB-to-DB9 adapter
Clear front panel cover sealed to NEMA 4X / IP65
NEMA-4X wall-mount enclosure with 1/8 DIN cutout
NEMA-4X wall-mount enclosure with 1/8 DIN cutout plus
IPC |
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$30
NC
$19
$39
$40
$140
$180 |
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Order from
distributors for shipment to USA or Canada. |
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Order online for
international shipment. |
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