Measured values
HMG 4000
Edition 2016-03-08 - V01 R04
[50]
Part No.: 669950
Formula
You can enter a formula here with
which the other measurement
channels can be offset.
Example: "(A + B) * C2 + K4"
The channels are addressed via their
port letters and channel number. If
a port has just one channel, the
channel number can be omitted.
The following operations are
possible:
+, -, *, /
abs, sqr, sqrt
(absolute value, square, square
root)
ln, log, e, x
y
Setting the evaluation order
with brackets
If there is "division by 0" in the calculation or if one of the outlet channels has left
the measurement range, the measured value will be identified as "
invalid
".
Unlike the mathematical rules, the root of a negative number does not result in an
error. Instead, the result corresponds to the negated root from the sum of the
radians. As such, the result of "
sqrt (-4)"
is "
-2"
. The same applies for the logarithm
(log, ln).
This usually corresponds to the technical ratio.
e.g. a flow rate can be measured via the fall in pressure at an orifice. Here, the
root is taken from the pressure differential. If the pressure differential is negative,
this means that the flow direction is reversed. In this case, the HMG provides the
correct results.