100mA + 10mA). An I/O module can only supply about 2,6A (3,0A minus the maximal battery charging
current and the I/O circuit board current drain). When LED’s are connected to these outputs, you should
place a 1K resistor in series with the LED. Through this, the current drain of each connected output is
reduced to 10mA. With 48 LED’s connected the maximal current drain will be 490mA, which can be
supplied by the I/O module without any problems.
RO module
The RO module gets its power from the RS-485 bus and has an own current drain of maximal 50mA. Using
the recommended RS-485 bus cable, this will mean a voltage drop of 0,5V for every 100 meters. The RO
module needs at least 8V to work properly. The maximal length of the cable between the RO module and the
nearest power supply will be 400 meters.
Wireless interface
The wireless interface obtains its power from the RS-485 bus and has an own current drain of 43mA. Using
the recommended bus cable, this will mean a voltage drop of 0,43V for every 100 meters. The wireless
interface needs at least 8V, in the worst possible situation (no mains power and minimal battery). The
maximal length of the cable between the wireless interface and the nearest power supply with a voltage drop
of 2V will be about 465 meters.
Printer module
The printer module gets its power from the RS-485 bus and has an own current drain of 140mA. When using
the recommended RS-485 bus cable this will mean a voltage drop of 1,4 V for every 100 meters. The printer
module needs at least 8V to function properly. The maximal length of the cable between the printer module
and the nearest power supply will, with a voltage drop of 2V, be about 140 meters.
AlphaCom ISDN dialler
The AlphaCom ISDN dialler is available in two different versions, the AlphaCom plug-on, which is plugged
on the AlphaVision NG circuit board, and the AlphaCom II, which is placed in a metal casing and is
supplied with its own power supply. Both versions are equipped with an RS-485 connection, but only the
plug-on version gets its power from the RS-485 bus. The AlphaCom plug-on has a current drain of 150mA.
The AlphaCom II dialler has its power supply and back up battery and uses the RS-485 bus only for
communicating with the AlphaVision NG control panel. The AlphaCom II dialler uses 150mA and can
supply 350mA @ 12VDC. Do not forget that the battery recharge current drain has to be subtracted from
this! The battery is charged with a stabilized current, which can be adjusted, and is charged through a
resistor. By default, the current value is set to 13,8V.
The AlphaCom II dialler can be placed at the maximal distance from the control panel, taken that the cable
recommendations are followed.
DLM-100 GSM dialler
The DLM-100 GSM dialler has its own power supply, which can only be used for the DLM-100. The dialler
checks the battery every 5 minutes. When the battery voltage is too low, the DLM-100 will report this
automatically. The DLM-100 also checks the mains power. When the mains power fails, a report will be
send 30 seconds later. When the mains power is restored a restore report will be send 20 seconds later.
The DLM-100 GSM dialler can be placed at the maximal distance from the control panel, taken that the
cable recommendations are followed.
Attention: Because the battery of the DLM-100 has a low capacity, we strongly advise you NOT to connect
any current draining modules to the outgoing RS-485 connection.
AlphaVision NG installation manual Rev. 2.0 27-08-2003 Blz. 32/101
