Bellcall Digital Door Entry System
PD-083 Issue 3A
Installation and Operating Manual
Page 8 of 46
Design Considerations
Equipment List
A Bellcall digital audio systems can vary in content significantly, but comprise of the
following items: -
A number of phones, either the new BS-A phones or the older BC801
None or more BSC4-AD Audio controllers as required to break up the wiring into 4
smaller segments each.
Then for each door:- Either
BCP1(F) Integrated door panel and controller.
Or a door panel and controller.
BCP1/LCP Vandal resistant panel LCP option.
BCP1/VR(S) Vandal resistant panel standard VR option.
BSD-DIG Door controller.
61 speech unit.
And common items
Power supply, see below for alternatives.
203 Fail-secure lock release, alternate types available.
DDA
panels (Contact sales for further information).
Equipment Options
At the simplest all the door controllers and phones can be connected on a single bus, and
this works for smaller systems. However there is a data limitation of 128 items (phones or
controllers) on a single bus, and a total cable length limitation of about 1000metres.
BSC4-AD audio controller. This controller performs group isolation and allows both of the
above limits to be overcome. Each controller can split the phones into 4 groups which are
isolated from each other. Installation and maintenance are also improved in that if a fault
develops in a group of common wired phones, the fault is already isolated to just those few
phones.
Full Isolation. This is achieved by using the above BSC4-AD controllers with just one flat
per output. When doing this it becomes more efficient to use the BSC4-AD’s ability to use
unprogrammed or programmed phones with the BSC4-AD decoding the address.
BSSW Gate switcher block isolator. This controller is used wherever 2 or more blocks of
phones share a common door or gate and independent operation of the blocks is required.
