7.9.2.2. Increasing the line length 
Stations with a loop resistor of up to 3000 ohms (including station)
can be connected to the SLMAR.
Up to two analog stations are permitted per port.
An extended station (extended loop) in talk state requires roughly
the same amount of power as two normal analog stations.
The ringing ac current for the station is generated on the board.
The ring current from the ring generator is not used.
The limit for the extended stations is the power supply of the system.
During configuration of the station the board checks if the increased
power supply is necessary. If it is not required, a message indicating
that a standard SLMA should be used is output.
When equipping the system, the configurator must ensure that there
are no hot spots.