Heise PTE-1, Operating Manual

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Revision 4.6 3/2004
2 – The percent life remaining is based on the character-
istics of standard 9 Vdc alkaline batteries. Use of other
batteries types, such as; zinc, lithium or rechargeable
NiCad batteries, will result in inaccurate estimation of
remaining battery life in both percent indication and bar
graph indication.
Step 1 Install new batteries as outlined in the base unit
start up section of this manual (Section 3.1).
Step 2 Turn the HHC on.
Step 3 With the HHC operating and displaying pres-
sure press the battery check key, designated BAT CK:
BAT
CK
The HHC will respond by displaying:
+x.xxV +xx%
Note:
Installation of two new 9 Vdc alkaline batteries
will produce an initial voltage measurement of 9.0-9.5
Volts on the calibrator. If the value measured is signifi -
cantly below this level it is likely that the batteries have
degraded in storage and that they will provide less than
the 30 hours of operation expected from a set of fresh,
fully charged batteries.
Step 4
Use the right arrow key to restore the bar graph
to the full scale. The percentage value displayed will
refl ect the adjustments made to the bar graph.
The number of highlighted segments in the bar graph
will automatically reduce as the remaining battery life is
reduced through the use of the HHC.
Important Note:
It is recommended that batteries be re-
placed when the low voltage icon appears on the instru-
the low battery icon appears is approximately 1 hour.
****WARNING****
Batteries must be changed in a non-hazardous environ-
ment for all HHC units.
Section 21.0 Dual Sensor Functions
The calibrator is equipped with fi rmware that can auto-
matically add the measured pressure values from two
installed Quick Select pressure modules or to subtract
the value measured by the Quick Select module installed
in the right module bay from the measured value of the
Quick Select value in the left module bay. This optional
fi rmware allows for the following:
The ability to subtract the measured value from the left
module of the measured value derived from the right
module allows for simplifi ed measurement of what are
commonly referred to as high-line” or elevated static
differential pressures. A complete description of this
capability is provided in Section 21.2 entitled Dual
Sensor Differential Pressure Measurement.
2 – The ability to add the measured values of the two
installed Quick Select pressure module allows for the
addition of a measured barometric pressure from an
absolute pressure module to the measured pressure
from a gauge or differential pressure. This capability can
come in handy and save money by allowing the use of
gauge measurement Quick Select pressure modules for
absolute pressure measurement activities.
Section 21.1 Accuracy of Dual Module
Measurements
The accuracy of measurements made using the differ-
ence or sum of 2 modules is a function of the full scale
range of the Quick Select pressure modules used and,
in the case of differential pressure measurements, the
magnitude of the dp range.
For dual sensor summation measurements:
The worst case inaccuracy would be the sum of the
inaccuracies of the two Quick Select modules used for
the measurement. For example, if the measurement is
made with two +0.1% full scale modules the maximum
inaccuracy would be +0.2%. In actual use, it is gen-
erally acceptable to use the Root Sum of the Square
(RSS) method of determining the accuracy of a multiple
component measurement system. Using the RSS method
the accuracy of the dual module summation is approxi-
0.14% of span.
For dual module differential pressure measurement:
The accuracy of the dual module differential pressure
measurement is a function of the full scale range of the
Quick Select pressure modules used in the measurement
process and the magnitude of the dp range. In general,
the accuracy for the dp measurement for dp ranges less
than 10% of the rated range of the Quick select modules
used is ±0.37% of dp range ±1 count. For dp ranges
greater than 10% of the range of the Quick Select pressure
module installed, the accuracy of the dp measurement is
±0.37 % of the dp range x 0.1(R1) where R1 equals the
ratio of the module full scale to the dp full scale (Sensor
full scale/dp full scale).
Section 21.2 Setting Up Dual Module Differential
Pressure Measurement
Step 1 With the calibrator off, install the two Quick
Select pressure modules in the calibrator. Be certain
to install the module so that the modules are in the
desired module bays. The subtraction process is always
defi ned as the subtraction of the measured value of the
right module from that of the measured value of the left
module (d/p = Left measurement value – right measure-
ment value)