phone versuscat5

[Cajun Cheesehead]

Is there a maximum distance you can go with a phone line between controllers before you should consider using Cat5?

What are the advantages/disadvantages of each option?

[Max-Paul]

I dont know what would be the max distance using phone wire, but I will give you my 2 cents worth about Cat 5 wire versus phone wire. Although one question for you. Ok there is one RJ-11 connector. How are you going to leave the controller with the two other connectors being RJ-45?

Ok most phone wire is not twisted like Cat 5 wire. The twist helps to eliminate noise on the wire. Thus Cat 5 wire will reduce the chances that noise will give your controller problems. Something to consider when selecting between the two. Also I do not know the impedence of phone wire, but Cat 5 is close to 100 ohms which is I think if I remember correctly is the standard impedence of RS-485 spec.

[Denny]

I use a mix of cat5e and phone wire without problems. My longest phone line runs use 100 foot lengths and I have five at that length. Just make sure you connect the phone lines to the appropriate jacks as shown in the manuals. Also, use care when installing the phone line to the RJ-45 connector. The phone line plug only has four connectors and the RJ-45 has six, so make sure you get it plugged into the middle of the RJ-45.

I think Tim Fischer has said in the past that he uses phone line also.

[cmoore60]

As was stated there are people that use only phone wire. The only requirement I believe is has to be cat 5 to the first controller (might be wrong there). The phone wire from the previous controller goes to the RJ-11 connector( left connector) then when going to the next controller you will plug your phone wire plug into either of the other connectors. As was stated....make sure you have it in correctly.

The reason for the differencein connections. Cat5 cables are typically wired in a straight thru pattern, pin 1 to pin1. Telephone wire is typically wired in a crossover pattern, pin 1 to pin 4.

Chuck

[Max-Paul]

Denny and Chuck,

Thanks for catching and filling in on the RJ-45 jack. I hadnt paid close attention to the jack and did not remember that these jacks had that little notch that accepts the RJ-11 connectors too.

Some else to try to remember.

Thanks

[Steven]

cmoore60 wrote:

The only requirement I believe is has to be cat 5 to the first controller (might be wrong there).

You can use phone wire to the first controller.

The rule on the jacks is this: If you are using a properly wired phone cable (pin 1 connects to pin 4 on the other end, and pin 2 connects to pin 3), then one end plugs into the RJ-11 and the other end plugs into a RJ-45. If you are using phone wire for the first controller, then it plugs into the RJ-45 on the SC485 or USB-RS485 and the RJ-11 on the first controller.

[bwaldrep]

cmoore60 wrote:

Telephone wire is typically wired in a crossover pattern, pin 1 to pin 4.

I have never seen a telephone cable wired like that. In fact doing so, would switch the tip and ring. which can cause issues for some phones.

[-klb-]

It would only switch tip and ring if it were not conventional for the phone cables to be wired with the rollover pinout, and the products that work with them to take it into account.