2N Helios IP Video Kit Installation Manual page 15

Connection of Keypad/Buttons
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2N Helios IP Video Kit is equipped with an interface for connection of an external
matrix keypad or up to 16 separate buttons; see the figure below:
The buttons are connected in a 4x4 matrix to the ROW1-4 (output) and COL1-4
(inputs) terminals. If you do not make use of all of the 16 buttons, you can leave some
of the ROW and COL signals unconnected. If you need one button only, connect it to
the ROW1 and COL4 terminals.
The button function is programmable. You can set the numerical keypad buttons to any
matrix position (0 to 9, *, #) or configure one of the 16 buttons for dialling a telephone
directory position. Refer to the
Caution
Connection of External Loudspeaker
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2N Helios IP Video Kit is equipped with an integrated 10W power amplifier of class
D. The amplifier output is available on the SPEAKER+ and SPEAKER- terminals.
The maximum power is achievable with a 4Ω loudspeaker only. The higher the
loudspeaker impedance, the lower the maximum power output; refer to the table
below:
Loudspeaker impedance
®
2N TELEKOMUNIKACE a.s., www.2n.cz
2N
Errors such as false keystroke detection may occur in installations with
strong EMI. Therefore, make sure that the keypad or button cables are
carried in a trunk separated from the power cables and are as short as
possible (up to 1m).
4Ω (min)
8Ω
16Ω
32Ω
64Ω
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Helios IP Configuration Manual
Maximum power (at +20dB)
for details.
10W
5W
2.5W
1.2W
0.6W
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