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K-Factor Scaler |
 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. |
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| 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. |
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| 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: |
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Max Voltage |
30 Vdc |
Max Power |
0.25 W |
Pulse Type |
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using internal pull-up
resistor |
VH = Power input voltage
- 0.7 Vdc |
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VL = Less than 0.4 V
@ max input power |
using external pull-up
resistor |
VH =
Input voltage to external pull-up resistor |
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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: |
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Model B220-885 |
Killark aluminum-capped
elbow - Y3 CSA approved Class I, Div 1 & 2, |
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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 |
& B220-881 |
approved Class I, Groups
B, C & D: Class II, |
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Groups E. F and G; & Class
III |
Certifications: |
CSA ordinary locations |
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Pollution Degree 2, Overvoltage
Category III |
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| Features: |
| Models |
B220-880 |
B220-881 |
B220-885 |
| K-factor |
X |
X |
X |
| No. of Digits |
8 |
8 |
9 |
| Range |
1 to 99,999,999 |
1 to 99,999,999 |
1 to 99,999,999 |
| K-Factor Entry |
Rotary Switch |
Rotary Switch |
Electronic Input |
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| Model B220-880 |
Model B220-881 |
Model B220-885 |
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