Three-Way Calling
This is one the new features that is available from BT
Network Services, for this feature to work correctly
the telephone line must have this service enabled
(contact BT for further details).
When the DC58/58M is triggered the unit checks
for incoming ringing or off hook (someone trying to
block the call). The unit then sends a "Recall"
signal, which is detected by the exchange as a
request for a new line. With a new line available the
DC58/58M then attempts to connect with the
ARC.
If the DC58/58M is connected to an older pulse
dial only exchange, the numbers being dialled
must be selected to "Pulse" dial,
see "Telephone
Numbers" on page 11.
This will disable the
three-way calling facility as it is not available on the
older type exchanges.
Line Fault Monitor
The line fault monitor continuously monitors the
PSTN line and will detect:
l
The loss of line voltage (cut line)
l
A line voltage less than 35V (parallel telephone
off hook)
l
An incoming ringing signal that will try and
prevent DC58/58M operation
If the DC58/58M is used on a shared line then the
line fault monitor can be selected to only monitor
a cut line by setting the "HI/LO SECURITY" option to
"LO". It is also recommended that "Three-Way
Calling" is used (see above) so that the security of
the system is not compromised.
Temporary Out of Service
In addition to the line fault monitor, the DC58/58M
can be programmed to perform a more detailed
line test at pre-set intervals. The DC58/58M will
seize the line and dial all digits but the last one of
telephone number 1. If the unobtainable tone is
NOT detected it is assumed that the line is healthy
and the unit releases the line. If the unobtainable
tone is detected, a line fault is signalled.
Point ID Extended Format
This is a new format which is used to send
additional fast format data to the alarm receiver.
The additional information can be used to
indicate the circuit that caused the alarm, the user
that set/unset the system etc. For the DC58/58M to
send this additional data, the unit must be
plugged on to a Menvier control panel that
supports "Point ID Extended Format"' and report to
a compatible alarm receiver.
Modem (DC58M Only)
When a call is made to the alarm site the DC58M
will pick up the call and attempt to connect to the
modem that is connected to the P.C. If successful
the communication link is established and data
can be transferred. When the Modem is on-line
the red LED on the DC58M flashes continuously
until the communication link is broken. If during the
Modem operation the control panel generates an
alarm which is required to be transmitted to the
ARC, the DC58M will suspend the Modem
operation and attempt to communicate with the
alarm receiver.
6
Operation
DC58/58M Installation Instructions
