Extended Counter

• Available in three digit heights: 0.56" for panel mounting, 1.0" (Mighty-1) or 5.0" (Mighty-5) for long-distance viewing.
• A/B and A/B-1 (draw) arithmetic functions.
• Applicable to rate or total.
• Frequencies from 0.005 Hz to 1 MHz.
• Independent scaling for each channel.
• Inputs from NPN or PNP proximity switches, contact closures, digital logic, magnetic pickups down to 12 mV, or AC inputs up to 250 Vac.
• Update rates to 25/s.
• Selectable "count by" of 10 or 100 with rounding.
• Isolated 5, 10 or 24 Vdc excitation supply to power sensors.
• Green or red 6-digit LED display.
• Choice of isolated plug-in options for control and computer interface:
  dual relays, 4-20 mA & 0-10 V analog output, RS-232/485 serial I/O, low voltage AC & DC power.
• 1/8 DIN version environmentally sealed to NEMA-4X from front panel.
• 1/8 DIN version certified to UL 3101-1, CAN/CSA-C22.2, EN 61010-1 (CE Mark).

Description

The A/B ratio and A/B-1 draw meters are selectable operating modes of the Micro counter with Extended counter main board and FR dual-channel signal conditioner board.

• Ratio can be used to compare flow rates in two channels, the RPM of rollers or gears, or the speed of moving machinery, such as conveyor belts. Ratio can also be applied to scaled totals to compare two batches to be mixed. In this application, one meter is used to monitor the ratio of flow rates, and a second meter to monitor the resulting batch totals.

• Draw is obtained by subtracting 1 from ratio. Draw is often used to measure the elongation or shrinkage of material as it passes between rollers, or to monitor variation in the speed of rollers for tensioning.

Ratio and draw are similar, except that 1 is subtracted from ratio to obtain draw. The frequency of channels A and B is first measured and is then converted to rate in engineering units by multiplying it by the appropriate scale factor for that channel. Either rate can be displayed. The A/B ratio is then taken mathematically by the meter, and 1 is subtracted for draw. The result can be multiplied by a multiple or 10 from 0.0001 to 100000, and the decimal point can be set to display the result with the desired precision up to six digits.

Fast, High Resolution Measurement

The Micro counter determines frequency by timing an integral number of periods over a programmable gate time. The inverse period approach allows greater accuracy and faster update times than conventional meters which count signal pulses over a specified time interval.

Channel A accepts pulses from 0.005 Hz to 1 MHz, while Channel B accepts pulses from 0.005 Hz to 250 kHz. At the minimum gate time of 10 ms, update rates can be up to 25/second. Such fast response is ideal for peak capture and for alarm and control applications. Variations in the displayed reading can be reduced by selecting a longer gate time. An adaptive filter can further reduce variations due to noise while rapidly responding to actual changes in the signal.

Universal Signal Conditioner

The Micro 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. Jumper selections provide optimum operation for different sensor types and noise conditions. A built-in isolated 5, 10, or 24 Vdc excitation supply can power proximity switches and other sensors, and eliminate the need for an external power supply.

Other Features & Options

Plug-in isolated analog output, dual setpoint controller, and RS-232/485 serial communications boards can upgrade Micro and Mighty Series meters from stand-alone monitoring to system interface and control. Micro Series meters can be powered from 95-240 Vac ±10% and 95-370 Vdc, or optionally from 12-34 Vac and 10-48 Vdc. Any setup functions and front panel keys may be locked out for simplified usage and security. The popular 1/8 DIN version with 0.56" high digits is environmentally sealed to NEMA-4X (IP65) from the front when panel mounted, and is available with red or green LEDs.

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
-12 mV to +12 mV, +30 mV to +60 mV, -30 mV to -20 mV,
-150 mV to +150 mV, +350 mV to +600 mV, -600 mV to -350 mV,
-1.15V to +1.15V, +1.25V to +2.1V, -2.1 V to -1.25V
Selectable: 1 MHz, 30 kHz,  250 Hz
Selectable: 0, 3, 50 ms

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

Controlling the Mixing Ratio of Two Fluids

Comparing Fluid Inflow & Outflow

Controlling Coating Thickness on a Film

Synchronizing Two Conveyor Lines

Measuring Draw for Elongation