Honeywell Minitrend QX, User Manual

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43-TV-25-30 Iss.6 GLO Aug 07 UK 281
In this application, the flow meters are connected to inputs 1, 2, 3 and 4 at the rear of the
recorder, and these are recorded on Pens 1 to 4
P1=A1
P2=A2
P3=A3
P4=A4
Pen 5 has the script above, which records and displays the highest flow rate of the four.
Pen 6 is set to record and display the input (between 1 and 4) that is the highest rate
P6=GLBV1
Example 2
In the same application as above, the user has noticed that whilst flow meter 2 normally has
the highest flow rate, on occasion a surge in flow meter 3 causes problems. The user needs
to monitor the two inputs and count the number of times flow meter 3 reading exceeds that
of flow meter 2.
The code consists of the two flow meter readings, and a change counter that totals the
number of times that flow 3 exceeds that of flow 2.
The pseudo code is written as:
If flow meter 3 has a larger reading than flow meter 2, check to ensure that it was already
greater than meter 2, if it was return the latest change count value.
If it was not greater than meter 3 last time, set a flag to indicate a change and increment the
change counter by 1, then return the latest change counter.
If flow meter 3 is less than 2, simply return the change count value with no increment.
Pen 7 is used to implement this script and is implemented as follows
GLBV1=3; If yes, then set display indicator to meter 3
return A3; And return the current flow reading
}
else If none of the above are true, then 4 is biggest
{
GLBV1=4; So set display indicator to meter 4
return A4; And return the current flow reading
}
NOTICE
Please note “Pn=” is not entered in the Maths Block and is assumed by the Recorder
e.g. To enter the equation P2=A2, the user would just type A2