Laureate™ Frequency, Rate & Period Meter
With dual, independently field-scalable channels

Standard Frequency / Rate Meter

• Two independently field-scalable channels selected by front panel pushbutton
• Frequencies from 0.005 Hz to 1 MHz
• Inputs from NPN or PNP proximity switches, contact closures, digital logic, magnetic pickups down to 12 mV, or AC inputs up to 250 Vac.
• 6-digit resolution at update rates up to 25/s
• Line frequency measurement to 60.0000 in a few line cycles
• 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
• Certified to UL 61010C-1 (UL mark), EN 61010-1 (CE mark) and RoHS

Extended Frequency / Rate Meter
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)

Options

• Low voltage power: 10-48 Vdc or 12-32 Vac
• 2 or 4 output relays, electromechanical or solid state
• 1 or 2 isolated analog outputs: 4-20 mA, 0-20 mA, 0-10V, -10 to +10V
• Serial communications: RS232, RS485, Modbus RS485, USB, USB-to-RS485 converter

The Laureate dual-channel frequency, rate and 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 pushbutton. 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 resolution 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.

• 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 arithmetic 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.

The FR dual-channel signal conditioner accepts inputs from 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 flexibility. Optional plug-in boards for communications and control include single or dual isolated analog output boards, dual or quad relay boards, and serial communications boards. 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.

Display

Readout
Display Range
Zero Adjust
Span Adjust
Indicators

6 LRD digits, 7-segment, 14.2 mm (.56"), red or green.
-999999 to +999999, XXXXEX notation beyond 999999
-999999 to +999999
0 to 999999
Four LED lamps

Inputs

Types
 
Signal Ground
Channel A Freq.
Channel B Freq.
Minimum Signal
Maximum Signal
Noise Filter
Contact Debounce

AC, pulses from NPN, PNP transistors, contact closures,
magnetic pickups.
Common ground for channels A & B
0.005 Hz to 1 MHz
0.005 Hz to 250 kHz
Nine ranges from (-12 to +12 mV) to (+1.25 to +2.1V)
250 Vac
1 MHz, 30 kHz, 250 Hz (selectable)
0, 3, 50 ms (selectable)

Update Rate

Freq. Technique
Conversion Time
Gate Time
Time Before Zero Out

Inverse period
Gate time + 30 ms+ 0-2 signal periods
Selectable 10 ms to 199.99 s
Selectable 10 ms to 199.99 s

Accuracy

Time Base
Span Tempco
Long-term Drift

Crystal calibrated to ±2 ppm
± 1 ppm/°C (typ)
± 5 ppm/year

Power

Voltage, standard
Voltage, optional
Frequency
Power Isolation

85-264 Vac or 90-300 Vdc (DC operation not UL approved)
12-32 Vac or 10-48 Vdc
DC or 47-63 Hz
250V rms working, 2.3 kV rms per 1 min test

Excitation Output (standard)

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

Analog Output (optional)

Output Levels
 
Current compliance
Voltage compliance
Scaling
Resolution
Isolation

4-20 mA, 0-20 mA, 0-10V, -10 to +10V (single-output option)
4-20 mA, 0-20 mA, 0-10V (dual-output option)
2 mA at 10V ( > 5 kOhm load)
12V at 20 mA ( < 600 Ohm load)
Zero and full scale adjustable from -99999 to +99999
16 bits (0.0015% of full scale)
250V rms working, 2.3 kV rms per 1 min test
(dual analog outputs share the same ground)

Relay Outputs (optional)

Relay Types
 
Current Ratings
 
Output common
Isolation

2 Form C contact relays or 4 Form A contact relays (NO)
2 or 4 Form A, AC/DC solid state relays (NO)
8A at 250 Vac or 24 Vdc for contact relays
130 mA at 140 Vac or 180 Vdc for solid state relays
Isolated commons for dual relays or each pair of quad relays
250V rms working, 2.3 kV rms per 1 min test

Serial Data I/O (optional)

Board Selections
Protocols
Data Rates
Digital Addresses
Isolation

RS232, RS485, Modbus RS485, USB, USB-to-RS485 converter
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

Environmental

Operating Temp.
Storage Temp.
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

Electrical Connections

AC Line Frequency

RPM and Speed

Flow Rate and Simultaneous Total

Combining Two Rates

Custom Curve Linearization

System-level Capabilities

The Laureate dual channel rate meter can independently scale, display and alarm two pulse input channels. All signal or alarm data can further be transmitted via RS-232 or RS-485, including peak readings and arithmetic combinations of the two rates. The displayed rates can also be transmitted as an isolated 4-20 mA or 0-10V analog output.