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Mbus Driver Guide
Network
The Mbus Network models the list of Mbus devices that the station can communicate with and
provides some of the controls and indications required to achieve this communication.
A two phase discovery technique has been adopted because of the long time delays
required between messages by various Mbus devices.
Specific information on the TCP/IP variant can be located at here.
Properties
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Inhibit Database Update
: When set this will prevent the internal database from updating. Discovery of new devices will still update the database.
For normal operation this can safely be set to true as the database will be updated as required, during discoveries.
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Network Database
: the Network Database provides storage for the Detected Devices on the Mbus network.
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Devices
: the MbusDevices show what devices are currently being monitored on the station.
The following properties can be customised on a per-device basis by enabling the MBusConfig under the relevant device. Devices without the MBusConfig enabled will revert back to using these network wide timings. By default the MBusConfig settings will be setup from the parameters that worked when discovering the device.
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Retry Count
: This should generally be 2 or higher. Many MBus devices will not respond if they are busy. The MBus specification states that 2 re-attempts should be made, if necessary.
It is generally recommended to increase this only on a per device basis using the devices MBusConfig equivalent setting.
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Initialisation Delay
: this delay is the period before the next command can go out following an Initialisation
request to the network (SND_NKE). This period should be adjusted to suit the
hardware installed on the network. Please consult the device documentation for suitable
values to be used.
E.g. The manual for the Kamstrup Multical 401 / 601 meter(s) define that after a Normalisation command (SND_NKE) the device will not respond for 3.5 seconds, therefore a suitable delay is 4 seconds.
If you have Kamstrup Multicals only on the bus then this would be best as a network wide setting, otherwise it should be configured under the devie's enabled MBusConfig.
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Inter Message Delay
: This is the delay after a message sequence has been completed / response has timed out before the next message can be sent. It it recommended to leave this at 300ms.
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Response Timeout
: This is the time it takes the device to answer. Expected transmission and response times are calculated from the devices baud rate currently being messaged. This property is the additional time on top of that allowed for the device to process the request and respond. Where a Jace has a high CPU load this may need to be increased, to accommodate the CPU load or for slow responding devices.
Actions
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Assign Address
: this action allows the operator to change the primary address on a singular connected device
(slave connected point to point with the master).
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Clear Network Database
: This clears all knowledge of currently detected devices. After all devices and points have been imported, this can be used in order to reduce the drivers overhead.
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