GORMAN-RUPP VG3B3-B, Инструкция по установке, эксплуатации и обслуживанию

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Thermo Scientific AquaSensors
™
AV38 Local Display and Controller User Guide 56
6. HOST COMMUNICATIONS
The AV38 can be set up to comm . The protocol selected is independent
of the Modbus protocol used by 38 te icks. When using Host
Communications, please refer to the selected communicati specific protocol setup and use.
Table 9: Host protocol vs. user's manual.
Host Protocol User’s Manual to Set up Address, Baud Rate and Parity
unicate with a Host Computer system
the AV to communica with the DataSt
r ons manual fo
Modbus RTU Modbus Com nication er Users M (MAN021CA) mu s Adapt anual
DeviceNet DeviceNet Co unication dapter Users ual (MAN022CA) mm s A Man
RS-232 DataStick Instruction Manual (MAN011DS): 0 bps, no parity, 8 data bits, 1 stop bit 960
Profibus Profibus-to-DataStick Communications Adapter Instruction Manual (MAN033CA).
Other Look for addendums on setting up other protocols that may be configured.
When Host Communications hardware is present, a host computer can communicate with the DataSticks
connected to the AV38.
There are two basic host communication modes; Gateway and Analyzer. When using either mode, it is better
ime.
host commands not handled by the AV38 must be forwarded to a DataStick. If the host makes a request too
often, the system will slow down. Hard-coded timers are rigid, and it is difficult for the programmer to know how
often is too often. If the host waits for a response from the AV38 before sending the next request, slow-downs
can be avoided and the system will be more flexible.
Gateway Mode
to program the host device to respond to events rather than perform desired operations based on elapsed t
This is because there is a limited bandwidth between the AV38 and the DataSticks connected to it, and any
Gateway mode is selected by setting the measure screen to Gateway using the LEFT and RIGHT arrow keys.
This disables all output and relay functions and allows the host computer to access all DataSticks connected to
the AV38 for remote measurement, calibration, configuration and diagnostics.
It is not possible to enter Gateway mode using the RIGHT or LEFT arrow keys when the Measurement is
ppmFCL2 (free chlorine concentration). This is because the AV38 needs to continuously acquire data from the
chlorine DataStick and, if necessary, the pH DataStick, in order to perform the free chlorine concentration
calculation. To enter Gateway mode in this case, first set the Chlorine Config | Measurement to ppmHOCL. If
a pH-compensated free chlorine concentration measurement is required, the host will have to perform the
calculation.
Analyzer Mode
It is also possible to communicate digitally with the DataSticks in the Analyzer mode where analog outputs and
relays remain active. In this mode it is possible for the host computer to communicate only with the two
DataSticks being displayed locally, i.e., mapped to the AV38’s two channels.