Danfoss AKA 245, Руководство пользователя

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Data collection in the master
gate way Data collection can take place in the gateway, defi ned to be the system’s master.
In connection with defi nition, start, stop and display of a data collection (logs), a switch will be
required for the PC. During the remaining time the gateway will take care of its own collection of data.
Data may thus be collected in a system which is not directly connected to a PC. The collected data may
subsequently be trans mitted to a PC from time to time, so that it can be displayed. The transmission
can, for example, be accomplished via a telephone connection.
Two diff erent log types can be established in the master gateway:
1) Food Safety logs (logs required by the authorities) and
2) AKA Service logs.
The diff erence between these log types is mainly the intervals at which data can be logged, and hence
the duration of the period of time the memory is able to accommodate.
Limitations:
- Max. 170 logs can be set up in a master gateway (120 Food Safety logs and 50 AKA Service logs).
- Each log will represent one controller
- Each log can max. contain 13 parameters.
- The time interval for Food Safety logs is between 15 minutes and 24 hours.
- The time interval for AKA Service logs is between 1 minute and 4 hours.
- The master gateway can totally contain about 60,000 data collections.
Examples of log capacities for diff erent sizes of systems are shown in Appendix C.
The log function will continuously collect and store data from the controllers connected to the
network for which the gateway in question is the master.
Defi nition, start, stop and display of a data collection (logs) must be carried out with system software
type AKM.
All logs in the master gateway are “rolling” (temporary) logs, in other words, the data will be
overwritten, if they have not been collected during the set period of time (deadline).
The log setup will be deleted and all collected data lost, if the system address of a master
gateway is changed or if the supply voltage is removed and the battery is defective or
dismantled.
If logs are deleted (one log or all of them), without the logged data having been stored, such data will
be lost. There will be no alarm when such deletion takes place.
When a log is started, data collection will not necessarily take place immediately, as all readings of
data will be carried out at set times after the log interval.
This means, for example, that for logs with 15-minute intervals the data will be read at times that are
multiples of the 15 minute-period, i.e. when the minute hand points to 0, 15, 30 and 45. Similarly, a log
with an interval of two hours will be read every other even hour, i.e. at 0am, 2am, 4am, 6am etc., up to
and including 10pm. And a log with an interval of six hours, at 0, 6, 12, 18. These fi xed logging intervals
cannot be changed.
If a log has been stopped for a while, and is then restarted, some data will be missing for the period
that was skipped.
The master gateway constantly controls all log setups via a simple check-sum calculation. If there is an
error, the log in question will be deleted. An alarm will now be given with information about the log
number.
18 Manual RS8DT102 © Danfoss 09/2004 AKA 245