atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's Adtran 624 question

Anyone know if an Adtran 624 can provide DID trunks? I have a customer that wants to use one for a PBX to break out 16 channels of loop start pots lines and 8 DID trunk paths, no data. I've been through the manual and it doesn't specifically use the term DID so I'm not sure.

I'm going to move this to T1 CSU/DSU's. I don't know why it couldn't if you're breaking out the channels from a CO switch. The DID would be between the CO and your switch not the CSU. At least that's my take.

Not sure about the 624, I would assume it could, but we all know what happens when you assume. I know the total access 750 can handle both lines and trunks. as long as you are using the correct cards.

If the 624 has a DSX-1 option you can provide both loop start (FXS) and digital DID. Pretty sure the 624 will not do analog DID.

You are correct Kyle.

The TA624 will not do analog DID. You need to get the TA850 with FXO cards in it to do analog DID's. Then you need the FXS cards for the loop start lines.

Keep in mind though that if you use analog DID's. In most cases you cannot use these DID trunks for outgoing calls only incoming. Even if the telco switch is set for two way it probably will not allow for outbound calls due to the fact that most switches do not put battery on did trunks and allow out dialing to b be recognized. Also I am not even sure if the adtran will support outbound even if it does.

If you are wanting two way then you need to use them at a t1 level. You can setup a 616 or 850 with DSX1 port on it to send the DID trunks out the DSX1 port and the loop start lines out the fxs ports.

Brian.

Thanks for the responses. I'm looking for analog DID as this is an older switch and can't do a T-1. The customer just happened to have an Adtran 624 sitting around from another site that they closed so they were hoping to use it. Any ideas on an inexpensive channel bank to use in this situation?

Not that other input here is wrong but can you tell me what you specifically mean by analog DID? If you mean an analog T1 using E&M, I am pretty certain that we used 624s with DSX ports configured for robbed bit and they worked just fine.

This unit was one of my favorite as far as flexability. It just did so much. Give it a shot. You might be surprised. Just make sure the code is updated and you set it to robbed bit on the channels passing out the DSX.

Analog DID's are analog, wink start trunks, capable of inbound-only service (on every channelbank I've used) and terminate on a 66-block as a single pair just like a loop-start line.

Kyle, may I ask why they are inbound only? Just curious.

I actually got a call back from Adtran today and they told me if the 624 was an L3 version, which it is, then the FXO ports can be configured for analog DID service to a PBX. I guess I'm going to find out if this is true or not.

Majestic, old school analog DID's are just designed that way, they don't give you dial tone when you go off-hook with a buttset, as they are for inbound traffic only. Two-way DID didn't come about until supertrunk T-1's came out(at least that's what we called them on the west coast)and then the next step was PRI.

I have not seen a setting for FXO in a TA624 Gen3 before. If it works please let us know for reference.


Majestic. To follow up on MichaelV.

The reason that analog did dont allow outbound is partially that it does not give out dialtone. Also it does not give out battery. It recieves battery. And a lot of systems up until a few years ago were polarity sensitive.
Here is a basic example.

IF you have a phone line (FXS). it goes into an fxo port on a phone system. The battery comes from the FXS Telco switch into the FXO port on the phone system. Battery on the FXS side not FXO side.

This example is basically the way it works on an analog DID just backwords. Also you get digits from the FXO on the telco into the FXS on the phone system.

As for Super trunks. What they are is basically E&M two-way trunks. Super Trunks are just a telco naming convention to make it sound better.

Ok I am familiar with the E&M two-way trunks as we've done lots of them with 624s out the DSX port.

Again, I stand firmly behind the Adtran Total Access product. While their support has been hard to get to in recent years, the product is well developed and feature rich.

Did a turn up with the CO friday. Got 16 1MB loop start lines and 8 analog DID paths. Gen 3 624 works great for this app.

Glad to hear everything went smoothly.

Also good info on the Gen3 624.

There are multiple versions of the TA624.
You can get them with 24 FXS ports or you can get them with 16 FXS and 8 FXO ports. The 8 FXO ports, when set in DPT mode, will do analog DID's.
We have a few out in the field doing this.

Brian