Laurel Electronics Laureate Frequency, Rate & Period Meter - Manual

LAUREL ELECTRONICS INC., 3183-G Airway Ave., Costa Mesa, CA 92626, USA • Tel 714-434-6131 • www.laurels.com 1
LAUREL
ELECTRONICS, INC.
Laureate™ Frequency, Rate & Period Meter
With dual, independently field-scalable channels
Features
• Frequencies from 0.005 Hz to 1 MHz
• 6-digit resolution at update rates up to 25/s
• Selectable "count by" of 10 or 100 with rounding
• Universal AC power, 85-264 Vac
• Isolated 5, 10 or 24 Vdc excitation supply to power sensors
• NEMA 4X, 1/8 DIN case
• Optional serial I/O: Ethernet, USB, RS232, RS485, Ethernet-to-RS485 converter
• Optional relay outputs: dual or quad relays, contact or solid state
• Optional isolated analog output: 4-20 mA, 0-20 mA, 0-10V, -10 to +10V
• Optional low voltage power: 10-48 Vdc or 12-32 Vac
• Optional Extended Counter: all capabilities of Standard counter, plus
- Rate and total simultaneously
- Custom curve linearization
- Arithmetic functions A+B, A-B, AxB, A/B, A/B-1 (draw)
Description
Standard Counter Version:
• The Laureate dual-channel frequency, rate & period meter
is a basic operating mode of the Laureate counter with the FR
signal conditioner board. It can display frequency from 0.005
Hz to 1 MHz, rate in engineering units, and period (inverse of
frequency). The normal displayed value can range up to
999,999 counts. Above that level, the display will flash and go
into four-digit XXXXEX scientific notation. Each channel (A or
B) may be independently scaled for frequency, rate or period.
The displayed channel is selected via a front panel push-
button. Examples of applications are the accurate display of
AC line frequency, RPM, speed from proximity switch inputs,
and flow from turbine flow meter inputs.
• Fast, high resolution measurements. The Laureate counter
determines frequency by timing an integral number of periods
over a specified gate time, and then taking the inverse of
period. Rate is obtained by multiplying the input by a scale
factor. The inverse period approach allows greater accuracy
and faster update times than conventional meters which count
signal pulses over a time interval. AC line frequency may be
accurately measured to 50.0000 or 60.0000 Hz in a few line
cycles. 1000 Hz signals may be measured to 0.01 Hz resolu-
tion at up to 25 readings per second. Fast response is ideal
for alarm and control applications.
• For noise reduction, a count by 10 or 100 feature with
rounding is selectable. Variations in the displayed reading can
also be reduced by selecting a longer gate time. An adaptive
digital filter is selectable to reduce variations due to noise
while rapidly responding to actual changes in the signal.
Extended Counter Version:
• Rate and total simultaneously. One channel can display
total while the other displays rate. The selection for either
channel is via a front panel pushbutton. This mode is ideal for
flow applications when the same signal is applied to both
channels.
• Custom curve linearization. Exceptionally accurate custom
curve linearization allows linearization of the low end of
turbine flowmeters. For setup, up to 180 data points can be
input into a spreadsheet or text file by the user. The computer
then calculates nonlinear segments, which are downloaded
into the meter via RS-232. The Extended version allows
linearized rates to be totalized.
• Arithmetic functions. The Extended counter makes arith-
metic functions available, namely A+B, A-B, AxB, A/B and
A/B-1 (draw). For example, A+B allows two input flows to
be summed for total flow, while A-B allows outflow to be
subtracted from inflow for net flow. If transducers with a
frequency output are used, AxB allows horsepower to be
displayed based measured torque and RPM, or based on
force and velocity. A/B can be used for the proper mixing of
ingredients, while A/B-1 (draw) is used to compare rates for
stretching or tensioning.
Inputs to the FR dual-channel signal conditioner can be
proximity switches with PNP or NPN output, TTL or CMOS logic,
magnetic pickups, contact closures, low-level outputs from
turbine flow meters down to 12 mV, and high-level AC line inputs
up to 250 Vac. A built-in isolated 5, 10, or 24 Vdc excitation
supply can power proximity switches and other sensors, thus
eliminating the need for an external power supply.
Designed for system use. Optional plug-in boards include
Ethernet and other serial communication boards, dual or quad
relay boards, and an isolated analog output board. Laureates
may be powered from 85-264 Vac or optionally from 12-32 Vac
or 10-48 Vdc. The display is 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. A built-
in isolated 5, 10, or 24 Vdc excitation supply can power trans-
ducers and eliminate the need for an external power supply. All
power and signal connections are via UL / VDE / CSA rated
screw clamp plugs.