Aalborg DPM Series, Руководство по эксплуатации

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8 RECALIBRATION
The recommended period for recalibration of the DPM flow meter is once
annually.
Aalborg
£
Instruments’ Flow Calibration Laboratory offers professional
calibration support for Mass Flow Meters using NIST-traceable precision
calibrators under strictly controlled conditions. NIST-traceable calibrations
are available.
9 RS-235/RS-485 SOFTWARE INTERFACE COMMANDS
9..11 G Ge en ne erra al
The standard DPM meter comes with an RS-232 interface; an RS-485
interface is optional. For the RS-232 interface, the start character is
! and
two hexadecimal characters for the address must be omitted. The protocol
described below allows for communications with the unit using either a
custom software program or a “dumb terminal”. All values are sent as print
ASCII characters.
For the RS-485 interface, the start character is always ! . The command
string is terminated with the equivalent of a carriage return; line feeds are
automatically stripped out by the DPM. (See Section 3.3 for information
regarding communication parameters and cable connections.)
9.2 Commands Structure
The structure of the command string is as follows:
RS-485 !<Addr>,<Cmd>,Arg1,Arg2,Arg3,Arg4<CR> Example: !11,F<CR>
RS-232 <Cmd>,Arg1,Arg2,ARg3,Arg4<CR> Example: F<CR>
Where:
!
Start character ** ( must only be used for RS-485 option )
Addr RS-485 device address in the ASCII representation of hexadecimal
(00 through FF are valid). ** (
must only be used for R-485 option )
Cmd The one- or two-character command (see examples below)
Arg1 to
Arg4 The command arguments (see examples below). Multiple arguments
are comma-delimited.
CR Carriage Return character
CAUTION:
DPM flow meters can be only calibrated by Aalborg
Instruments' Flow Calibration Laboratory or an Aalborg authorized trained
and certified calibration facility.