DATA-LINC GROUP
17
SRM6200E-SLC User’s Guide
PN 161-09990-002C
rev 3/29/04
Number of Disconnects
If, during the course of performing a link test, the link between the master and the slave is broken, and the radios lose carrier
detect, the occurrence is recorded in the Number of Disconnects value. The value indicates the total number of disconnects
that have occurred from the time the link test started until the radio was put into config mode. Under normal operating
conditions, the number of disconnects should be 0. One or more disconnects may indicate a very weak link, the presence of
severe interference problems or loss of DC power to the Master or Repeater if one is present.
Note: A remote and/or repeater will record a disconnect if the system master is placed into configuration mode
or has power interrupted while the remote and/or repeater is linked to the master.
Radio Temperature
The radio temperature value is the current operating temperature of the radio in degrees C (Celsius.) For proper operation,
SRM6200E-SLC radio modems must be in the range of –40
0
to 75
0
C.
Multi-Point Operation
In a multi-point system, a radio modem designated as a master is able to simultaneously be in communication with
numerous remotes. In its simplest form, a multi-point network functions with the Master broadcasting its messages to all
remotes and the Remotes responding to the Master as appropriate.
Traditionally, a multi-point network is used in applications where data is collected from many instruments and reported back
to one central site. As such, the architecture of such a system is completely different from point-to-point applications. The
theoretical maximum number of remotes that can be configured into a multi-point network is a function of the data throughput
needed from each of the remotes. For example, if the network will be polling remotes once a day to retrieve sparse data,
several hundred remotes could be configured to a single master. If, on the other hand, each remote will be transmitting data
at greater levels then fewer remotes may be connected to the Master (the overall system will be closer to capacity with fewer
remotes).
The theoretical limit of a multi-point system is influenced by the following parameters:
•
Size of the blocks of data— the longer the data blocks the greater the system capacity
•
Throughput
•
The amount of contention between remotes
•
Use of repeaters— a single repeater in a multi-point network will decrease overall system capacity by 50%; more than
one repeater does not further decrease network capacity
