Method of operation
2
gas-net
C1 and C2
Page 2-7
negative quantities will be subtracted as soon as the total increment is positive
again.
The negative quantities can be deleted with a menu command. In addition,
accumulated negative quantities of a totalizing counter are always deleted when
the counter changes from the
disturbed
to
the
undisturbed
status.
A total flow rate is always positive; if a negative value is determined in terms of
figures, the total flow rate is set to 0.
Total flow rate and total count value are available as values across the system;
therefore, they can in particular be logged and output.
Totalizing counters can be set via the data interface using the GW-GNET+ soft-
ware during an online connection. Possibly retained negative quantities are
deleted when a totalizing counter is set. The setting of a counter is subject to the
user lock (numeric code).
The
Counters
module can file up to 20 totalizing counters.
2.6 Integrated RDT Module (for C2 devices only)
The
Integrated RDT
(
R
emote
D
ata
T
ransmission)
module implements the data
connection between the
gas-net
device and a remote center. The center
accesses the data traffic as a logical equal-access station via the integrated
RDT during an established data connection. The data transmission is imple-
mented according to DSfG specifications by means of a Class B DSfG interface.
If the device is equipped with a DSfG interface, further devices may be con-
nected via this interface. If such a local DSfG bus exists, the connection to the
center not only refers to the communication with the entities inside the device
but with the entire local DSfG bus traffic. With respect to data communications,
the RDT integrated in the device thus completely replaces an independent DSfG
RDT as other devices connected via DSfG may also use it.
The parameterization of the
gas-net
device assigns an own bus address
(EADR) to the internal
Center via RDT
entity
.
The data connection may use one of the following transmission media:
4
According to DSfG terminology an
Entity
is an enclosed functionality within a device. One
single entity is not necessarily identical with an enclosed device, as a device may contain
different entities with their own DSfG bus addresses.
