installing galaxy keypad

[Jeramy]

Hi, I have a galaxy flex which I'm trying to install myself!!! It says in manual that needs a 680ohm end of line resistor on the end of the bus. Then later on it shows a sketch that i need two resistors. One at the panel this time and one at EOL.
Q.1 Do I need to put 2 resistors only if I have multiple devices on the bus otherwise is one sufficient?
Q.2 I have seen videos stating the resistor can go on either + or - as it will do the same job is this correct?

 

[Jeramy]

Ok, I have connected one keypad and put resistor across A B on keypad and A B on panel and everything seems to be working. But still don't know if i need them both.

 

[GalaxyGuy]

The panel has the 680R built-in. When the jumper (next to the keypad connector) is fitted, the resistor is connected. If the jumper is removed, the resistor is not. Normally, you only remove the jumper if you fit two bus lines and the panel is in the middle, with a resistor at each end device on the bus.

 

[Jeramy]

Thanks for your help