how long can the cat 5 cable be

[james morris]

What is the longest the cat 5 cable from the bost box to the light o rama controler be thanks

[Brian Mitchell]

Using a serial port, it's 100ft to first controller

Using USB I believe it's 1000ft

[ErnieHorning]

From the LOR manual.

 

The Light-O-Rama (LOR) network of controllers uses the RS485 electrical protocol for data communication. This is a differential transmission standard which is highly immune to interference and allows for up to 4000 ft of cable. PC serial ports and USB ports limit cable length to less than 100 ft.

 

[james morris]

looks like from the rs485 the cable can be up to 4000ft to the controler ?

[-klb-]

Your total network can be 4,000 feet. If you use 4,000 feet, then you can only have one controller. Or at least you need the powered splitter to add more length. Or, with 3,000 feet to the first controller, you can have your controllers spread out über the following 1,000 feet.

[james morris]

thanks for the info now i understand 1 controler 1700 ft second controller 400 ft should be now problem if i understand it

[jsholla]

If you are going to have long lengths of RS-485 you should terminate the signals using a 100 Ohm resistor.  You can reduce the noise caused by such a long length and improve your signal integrity.  This terminator should only go on the last controller in the string.  This technique is describe in the RS-485 standard.  The resistor should be tied to the center two pins of either a 4-pin RJ-11 or 8-pin RJ-45.  I've attached a photo of the terminator that I made using a 1/4 Watt, 100 Ohm resistor.

[james morris]

thanks all for the info