User Guide

Example 5
This example illustrates how a BEKA two input Rate
Totaliser can be used to display the rate of ow and
the total ow of two reciprocating mud pumps and their
composite rates and totals i.e. pump 1 + pump 2. Each
pump has a displacement of 1 litre per stroke and a sensor
outputs one pulse per stroke.
The rate display is required in pump strokes per minute
and the total mud ow is to be displayed in m³ with a
resolution of 0.1 m³. Operating the Rate Totalisers front
panel * or & push button while the instrument is
functioning scrolls the display through pump 1, pump 2 or
the composite output of both pumps, but it does not affect
the instruments performance or output.
A pulse is to be transmitted by the Rate Totaliser for each
0.1 m³ of composite mud pumped i.e. pump 1 + pump 2.
Summary
Pump K-factor 1 pulse / stroke which is
equivalent to 1 litre.
Required total display 0.0 m³
Required rate display 0 strokes / minute
Pulse output 1 pulse / 0.1m³ of composite
     totalow.
Rate Totaliser Conguration
K-factor
FACtor-A pump 1 1 . 0
FACtor-b pump 2 1 . 0
Each output pulse from pump 1 and pump 2 represents
1strokewhichisequivalentto1litreofowthereforeno
further conversion is required.
Total display
5CALE . t-A 1000
5CALE . t-b 1000
The display is required in m³, therefore 5CALE . t has to
convert litres to m³. Each pump stroke displaces 1 litre
and there are 1000 litres in each m³.
Rate Display
5CALE . r-A 1
5CALE . r-b 1
dP rAtE 0
t-bA5E tb-60
The rate display is required in strokes per minute. Each
pulse from pumps 1 and 2 represents 1 pump stroke so
no further scaling is required for either input. Therefore
both 5CALE . r-A and 5CALE . r-b are set to 1. Rate display
resolution of 1 stroke is required, hence decimal point is
positionedaftertheleastsignicantdisplaydigitwhere
it is not visible. Selecting a timebase of tb-60 multiplies
the rate display by 60 to show pump stroke rate per
minute.
Pulse output
5ourCE 5CALEd
diVidE 1
An output pulse is required for each composite 0.1 m³ of
mud pumped. The Rate Totaliser outputs a pulse each
timetheleastsignicantdigitofthecompositetotal(pulse
inputA+pulseinputb)isincremented,irrespectiveof
whether the composite total is being displayed. In this
exampletheleastsignicantdigitofthecompositetotal
represents 0.1m³ so scaling is not required.
However, if an output pulse was required for every 1.0m³
of composite total that was pumped, diVidE would have
to be set to 10 i.e. 10incrementsoftheleastsignicant
digit(0.1m³perincrement)wouldoccurbeforeanoutput
pulse was produced.
11. Additional information
If additional information or help is required with Rate
Totaliser conguration, please call one of our sales
engineers who will be pleased to help.
Although Rate Totalisers are easy to congure on-site,
they can be supplied congured to customer specied
requirements with a printed slide-in scale card for no
additional charge.
BEKA associates Ltd.
Old Charlton Road., Hitchin, Herts. SG5 2DA UK Tel: [phone] Fax: [phone] e-mail [e-mail] www.beka.co.uk
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