The Blancett K-Factor Scaler converts a low level
frequency output (such as that from a Blancett turbine flow meter)
into a scaled square wave output signal. This adjustable frequency
divider converts or scales the turbine meter output into units
of measurement needed for a particular application and recognized
by almost any data collection device. The k-factor scaler provides
an amplified signal, even when a frequency conversion is not required.
The signal is more immune to electrical noise and capable of transmission
over longer distances than a raw turbine meter output.
Operating Principle
What is a k-factor? Every turbine flow meter
has a unique k-factor, or ratio of input pulses
per unit of flow. As the turbine rotates within
the flow meter an electronic pulse is created each
time a turbine blade passes the face of the magnet.
The total number of pulses equivalent to one unit
of flow is the k-factor. For a Blancett turbine
meter, the k-factor is the number of pulses equivalent
to
1 gallon, and every flow meter is labeled with
its unique k-factor. Because this k-factor applies
only to gallons, the k-factor scaler is a low-cost
and convenient way to convert the turbine output
into a different frequency, representing a different
unit of measure. See Figure 1.
Example: (Highlighted in yellow)
Blancett turbine flow meter has a k-factor
of 870. but PLC is configured for one pulse per
cubic meter
Enter 229855 into k-factor scaler
Now, the frequency output of the meter has
been converted to correspond with cubic meters
instead of gallons, and the square wave output
is compatible with the PLC.
Note: Divisors for other units
of measure are based on volumetric conversions
and are provided in the operating manual. For signal
amplification only, set the k-factor sealer to
1.
Models
Blancett offers two versions of the k-factor sealer:
switch-selectable (Model B220-880 or B220-881) and programmable
(Model B220-885). The switch-selectable version has a set of eight
rotary switches within the enclosure. The rightmost switch represents
the least significant digit of the k-factor number - for example,
if the desired k-factor is 4572, the switches will be set to 00004572.
The programmable version comes precalibrated from the factory
when ordered with a Blancett Series 1100 turbine flow meter. In
addition, it may be easily configured by the end-user through the
use of a Windows'''-based software utility kit (Model B220-900)
that includes a PC serial port interface cable. See Figure 2.
Specifications
Operating Temperature:
-22 °F (-30 °C)
to 158 °F (70 °C)
Inputs:
Magnetic Pickup
Frequency Range
0 to 4000 Hz
Trigger Sensitivity
30 mV p-p to 30 V p-p
Output Signal:
Max Voltage
30 Vdc
Max Power
0.25 W
Pulse Type
using internal pull-up
resistor
VH = Power input voltage
- 0.7 Vdc
VL = Less than 0.4 V
@ max input power
using external pull-up
resistor
VH =
Input voltage to external pull-up resistor
VC= (VH / Selected resistor
value + 47Ω ) • 47Ω
Pulse Length:
150us. 1 ms, 25ms, 100ms,
500ms, 1s, or auto mode selectable
Internal Pull-up
Jumper disable option
Resistor:
3.6K Ω
Enclosure Ratings:
Model B220-885
Killark aluminum-capped
elbow - Y3 CSA approved Class I, Div 1 & 2,
Groups C, D; Class II,
Div 1 & 2, Groups E, F and G: and Class III
Models 8220-880
Appleton GR conduit outlet
box GRL100-A & GRLB1 ODA, CSA
The Blancett K-Factor Scaler converts a low level
frequency output (such as that from a Blancett turbine flow meter)
into a scaled square wave output signal. This adjustable frequency
divider converts or scales the turbine meter output into units
of measurement needed for a particular application and recognized
by almost any data collection device. The k-factor scaler provides
an amplified signal, even when a frequency conversion is not required.
The signal is more immune to electrical noise and capable of transmission
over longer distances than a raw turbine meter output. 
