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Tareing via RS-232 (P Series only):
Tareing (or zeroing) the pressure gauge provides it with a reference point for zero pressure.
This is a
very simple but important step in obtaining accurate measurements
. It is good practice to “zero” the
pressure gauge each time it is powered up. If the pressure reading varies significantly from zero after
an initial tare, give the unit a minute or so to warm up and re-zero it. Zeroing the unit while there is any
pressure will directly affect the accuracy by providing a false zero point. If in doubt about whether the
pressure is zero, remove it from the line and open both ports to atmosphere before entering the Tare
command. If the unit reads a significant negative value when removed from the line and open, it is a
good indication that it was given a false zero. To send a Tare command via RS-232, enter the following
strings:
In Streaming Mode:
$$P<Enter>
In Polling Mode:
Address$$P<Enter> (e.g. B$$P<Enter>)
Sending a Set-point via RS-232 (PC Series only):
To send a set-point via RS-232, “Serial” must be selected under the “Input” list in the control set up
mode. To give controllers a set-point, or change an existing point, simply type in a number between 0
and 65535 (2% over range), where 64000 denotes full-scale pressure, and hit “Enter”. The set-point
column and pressure rates should change accordingly. If they do not, try hitting “Enter” a couple of
times and repeating your command. The formula for performing a linear interpolation is as follows:
Value = (Desired Set-point X 64000) / Full Scale Pressure Range
For example, if your device is a 50 PSIG full-scale unit and you wish to apply a set-point of 12.5 PSIG
you would enter the following value:
16000 = (12.5 PSIG X 64000) / Full Scale Pressure Range
If the controller is in polling mode as described in
Changing from Streaming Mode to Polling Mode
, the
set-point must be preceded by the address of the controller. For example, if your controller has been
given an address of D, the set-point above would be sent by typing:
D16000 followed by “Enter”
Содержание 16 Series
Страница 32: ...32 P Series All standard ranges P Series Differential Pressure All standard ranges 2 3 0 ...
Страница 33: ...33 PC Series All standard ranges PC Series Differential Pressure All standard ranges 2 ...
Страница 34: ...34 0 PC3 Series All standard ranges PCR3 Series All standard ranges ...
Страница 35: ...35 5 7 6 8 7 8 PCR Series Differential Pressure 5inH2O PCR Series Most standard ranges ...
Страница 36: ...36 PCD Series All standard ranges PCD Series Differential Pressure All standard ranges ...
