Aalborg DPC, Руководство по эксплуатации

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NOTE: Address 00 is reserved for global addressing. Do not assign the global
address to any device. When commands with the global address are sent, all
devices on the RS-485 bus execute the command but do not reply with an
acknowledgement
message.

The global address can be used to change RS-485 address for a particular device without local
display and joystick interface with unknown address:
1. Make sure only one device (whose address must be changed) is connected to
the
RS-485 network.
2. Type the memory write command with the global address:
!00,MW,118,XX,<CR>where XX, the new hexadecimal address, can be from 01 to FF.
After the new address has been assigned, a device will accept commands with the
new address.
NOTE: Do not assign the same RS-485 address to two or more devices on the
same RS-485 bus. If two or more devices with the same address are connected
to one RS-485 network, a communication collision on the bus will result, leading
to
communication errors.

Several examples of commands are shown below. All assume that the DPC controller has been
confi gured for decimal address 18 (12 hex) on the RS-485 bus:
1. To get currently selected Gas: !12,G<CR>
The DPC will reply: !12,G:0,AIR<CR>
(assuming
the Current Gas is #0, calibrated for AIR)
2. To get current Flow Rate Alarm status:
!12,FA,R<CR>
The DPC will reply: !12,FAR:N<CR> (assuming no fl ow alarm conditions)
3. To get a mass and volumetric fl ow reading:
!12,F<CR>
The DPC will reply: !12,50.0,50.3<CR> (assuming the mass fl ow is at 50% FS)
4. Set the Set Point to 100.0 % full scale:
!12,SP,100.0<CR>
The DPC will reply: !12,SP:100.0<CR>
5. Set the High and Low Flow Alarm limit to 90% and 10% of Full Scale fl ow rate:
!12,FA,C,90.0,10.0<CR>
The DPC will reply: !12,90.00,10.00,<CR>