The 2Wire System must be designed with 2 parameters in mind
- Maximum current absorption in both Standby and Active Operation
- Minimum Signal Level at farthest station
The Chart above details the current absorption and signal attenuation for all the devices that may be installed in your proposed system
Current Absorption
The 6922.1 Power Supply is rated for:
- 1000 ma Standby
- 1600 ma Active
Calculate the required standby and active current requirements for your proposed system and make sure the fall below the outputs listed for the 6922.1 power supply.
Example:
System with (20) 7539 Apartment Station + (5) 692D Distributors + (1) 41005 Entry Panel
- Standby Current = (20*10ma) + (5*0ma) + (1*170) = 375ma (Less than 1000ma Standby)
- Active Current = (1*160ma) + (19*10ma) + (1*360ma)= 710ma (Less than 1600ma)
Note: In larger systems, multiple 6922.1 are used to provide the larger system current needs. 692S.1 or 69RS.1 used to introduce the additional power supplies. The current calculations must be done for each 6922.1 in the system using the components connected to it.
Signal Level
All 2Wire apartment stations require a minimum -20dB signal level to operate properly
All entry panels provide a +16dB signal output. By adding all the signal losses caused by equipment and cable between the entry panel and the farthest station, you can determine if you will have a properly operating system.
In large systems, the signal amplifier 692M can be used to boost the signal level at crital locations in the system
Example:
System with (20) 7539 Apartment Station + (5) 692D Distributors + (1) 41005 Entry Panel
- (41005) – (4 692D IN/OUT LOOP) – (692D STATION OUTPUT)
- (+16dB )- (4*.2dB) – (20dB) = 14.8dB (More than -20dB)