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LO00-23 12 page brochure THE SENSOR
A Universal Power Cell works very well for process monitor-
ing. It has both a 4-20 milliamp and 0-10 Volt analog output
(powered by the unit) which can be sent to:
Local and remote load meters
Data collection systems
Programmable Controllers
Chart recorders
A built-in response adjustment lets you smooth out the
signal. Especially when working with lumpy materials or slow
agitators, the instantaneous or harmonic changes are usually
not of interest.
The capacity or Full Scale is easily changed to match the
load. A lot of processing equipment is oversized, so by reduc-
ing the sensor capacity to match the actual load, you
improve the sensitivity.
SIMPLE INSTALLATION
The self-contained Universal Power Cell is located in
the control cabinet. This means:
No holes in the tank.
No moisture or wash down problems.
No current and voltage transformers to complicate
the installation.
The convenience of one model to cover a wide variety
of applications.
OTHER APPLICATIONS
Processing facilities are now using power sensors to
monitor many other functions in their plant.
Pumps - Flow rate, loss of load, bearing failure.
Fans - Proper flow rates.
Grinders and Pulverizers - Maximize throughput.
Clarifiers - Avoid jam-ups.
Energy Input - Rubber mixing, for example, can be
monitored by the total accumulated power (KWH) into a
batch. The KWH-2 Meter takes the power signal from the
Power Cell and generates an energy signal.
One of the best applications for a
power sensor is for monitoring viscosity
changes in mixers and agitators. As a
batch is processed, the power changes
will reflect the viscosity changes and a
good batch will fit the normal profile
for that product.
The curves show a typical example
from a two speed high shear mixer. The
five steps of this process are clear to see:
Dry components are mixed at high
speed.
Liquid is added at slow speed.
Mixing continues at low speed and
the power/viscosity increases to the
desired level.
High-speed mixing begins and power
increases sharply.
As soon as the power/viscosity begins
to decrease, the batch is done.
Note that for the three batches run, the curves dont vary much. A deviation from this profile should raise a red flag. Also,
since power is linear with load changes it is easy to interpret and extrapolate the results at both the low and high end.
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0
DRY MIX
HIGH SPEED
ADD LIQUID
LOW SPEED
POWER DECREASE
SHOWS BATCH
IS DONE
BEGIN HIGH
SPEED MIX
BATCH 1
BATCH 2
BATCH 3
MIXER POWER READINGS
POWER KILLOW
A
TTS
PROFILING A PROCESS