Ground start or Loop Start

[endurevp]

So I hear that you should always bring Ground start trunks into the PBX rather than Loop start as Loop start will have disconnect supervision problems. Anyone else heard this and have any insight. I have never had issues with Loop start trunks on any Nortel PBX I have worked on. Maybe I'm lucky.

 

[acewarlock]

You have been lucky, I've been doing Nortel PBX for 28 years and LOOP Start has always been a problem.

 

[thattekguy]

Stick with ground to avoid problems.

 

[endurevp]

Good to know. Will keep it in mind. Thanks all.

 

[janaya]

Loop start only has a problem when disconnecting the call. I have been working on Nortel for a while and I'm sure, like most everyone here, I have had nothing but problems with Loop Start.

You have been living right.

Try at all cost to stick with Ground Start.

John

 

[KBIT3]

I've had limited experience with the Option11C but I've had constant problems with Loop Start. We had to switch to PRI just to fix the problems.

 

[PBlaney]

Most of the problems with disconnects on loop start trunks happens when you connect the calls to other peripherals. Voice Mails, IVRs, Call Center systems, trunk transfers, and even modems. I have alway gone by a rule of thumb.. That loop start trunks are for key systems and ground start are for PBX's

 

[johnpoole]

the reason ground start was used originally for pbx was due to "glare".. user dials 9 and answers an inbound call. that was due to the delay cause by ring cycle.. the connector makes the connection to the line, the next time ring cycle is sent to that connector group all connectors that did not have the b relay operated sent ring to the far end.. that delay in the mech days could be 2 or 3 seconds.. any time past that and up until answer supervision.. any user that dialed 9 could hit that trunk.. it was a problem when customers only had a handfull of trunks..

now with pri's a 50 plus trunks being more common the 3 or 4 trunks per switch.. glare is less of a problem.. if you deny trunk flash for hold, and make disconect timer 500 mil, ie half a second.. you can get by with loop... but why would you want to?

john poole
bellsouth business
columbia,sc