atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Telecom Service & Providers Ground start Loop

One more question, I have a Harris TS22AL set, and I noticed they sell a p3218-441 ground start cord for this set. Now, I shouldn't need this right? Example: If the CO dropped a white blue/blue pair, my normal butt set would be the red lead (negative) connected to the blue(ring) and the black lead will touch ground to initiate dial tone. So I shouldn't need the cord, right? thanks again

How many ground start lines do you do?

By the way we in this trade use white/blue-blue/white unlike CAT5.

And it doesn't matter how you have your butt set connected as long as you momentarily ground the tip.

-Hal

Hal if you look at Rain's profile he's an electrician; how many GS lines would he work on?

I know and that was my point! I don't even have a ground start cord.

-Hal

"I noticed they sell a p3218-441 ground start cord for this set"

Just another $%^@#* cord to get snarled! But where in the world are Telcos still installing ground start? I haven't run across one in years!

I brought this up a couple of years ago. I don't think I got a good answer (or maybe I did and forgot it [would someone please call the old folks home and make a reservation for me?]).

But anyway - Are the systems going in these days not using groundstart? Is glare and the associated problems with 3-party conferencing no longer a problem? Is it by choice or do the systems no longer support it?

I'm also going to assume that no one uses metallic E&M trunks anymore - but please feel free to correct me.

Sam

I moved this here as it's a better fit, especially if were going to get into the whys of GS trunks.

One I don't work on the larger systems and only have one location with GS trunks which is a fair sized motel.

I don't think the reason for GS trunks has changed it was to reduce the number of needed trunks by using two way trunks with GS to prevent glare. Glare was and probably still is an issue. On GS trunks the loops are open when idle so unless you dial to hit it for outgoing or an incoming call is ringing in the loop is open. Both the PBX and CO get an immediate indication when the loop is closed due to ringing or hitting an outgoing line at the PBX, preventing glare. On a loop start line there is a lag between the incoming ring and when the PBX or KSU see's it. So if you hit an outside line during that lag time you will land on the incoming call ie glare.

Hope that all made a little sense.

Where ever it's being ordered... I don't see too many GS services ordered either but at least for now, Telco equipment can still support GS.


E&M? Eeeee-yeah... I don’t see anything NEW ordered with E&M signaling anymore… And to be honest, even though it’s still a valid signaling option by the tariffs, I have not seen any gear that can support it in a long time. :shrug:

When we put in the Saks 5th Avenue Headquarters (Neax 22L. I think the install date must have been 1982 or so) we had hundreds and hundreds of 4W E&M trunks - all on copper. When I was at the Bank of NY (1986) we still had 4W E&M - but they were all on T-1s.

Matter of fact most of the Voice (PBX) T-1s I put in for years used 4W E&M as the signalling method.


Getting back to Ground Start, besides glare we used to have a real problem with Loop Start circuits on 3 party conference - if one of the parties hung up the other two people fouind themselves conferenced in with "If you'd like to make a call, please hang up the phone".

Have the new systems managed to address these issues, or are customers just ignoring these problems?


Sam

T1E&M Wink is still quite common. Most installs I've worked are either that or ISDN.