atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's Adtran CSU ACE Complete waste of money. It does Nothing!

Does anyone think that Adtran CSU ACE is a total and complete waste of money and is completely useless piece of equipment?


1. Its extremely expensive for a cheaply made piece of equipment.
2. Its not necessary because the phone system does not even need this piece to run. Just plug the T1 directly into the PBX's T1 card slot and it run fine.
3. The T1 facility card will tell you if it a network loss or equipment loss. So what is the point on a CSU ace?

If you PBX are not 50 feet away from the T1 circuit, is a CSU ACE just a waste of money? Do most people not even bother with the Adtran CSU Ace in front of their PBX system’s T1 card?

Please let me know.

Thanks.

Hmmm, been using them for years and they are very inexpensive and work well for the job they are required to serve.

They are indeed useful for "balancing" the line AND offer a piece of equipment between the telco and the T1 card for testing and protection.

I think the first 2 answer the third question, and by code where I am you have to have one and rightly so IMHO.

You are required by law to have one?

Can you let me know the difference between running a system with a CSU ACE and without a CSU ace? (even if your PBX is next to the T1 circuit?

Many other phone installers have kind of shrugged them off saying " Ugh, just plug the T1 line in and it works fine without them"

So you are saying they are necessary and required by law to have? All your customers have them?

Please let me know.

Thanks.

Yep. Of course I could plug the T1 straight into the smartjack and have to test if I have a bad CSU. Yep, they are required here and every one of my customers has one if they have a digital cicuit. They don't cost alot and most my system are in the 10's of thousands of dollars. The CSU is well worth it's cost IMHO.

The CSU, in my opinion, serves two purposes. First, it takes the hit and hopefully saves the T1 card in the PBX, sort of a sacrificial lamb. Second, it does provide a test point beyond the smartjack. If the distance is short (<133', the first LBO change on most CSU's) you don't technically *need* the CSU for any real reason. Many of the vendors I work with don't use them.

A CSU is required for line protection, LBO and as a test point. It's most important job is to provide "ones density" also known as "zero-code suppression". T1 network regulations allow only 15 consecutive zeros and a minimum average one's density of 12.5%. An idle T1 is mostly streaming zeros. When the one's density drops below 12.5% T1 repeaters start to loose there timing causing frame slips and possible loss of frame sync. When you loose frame sync you drop calls. The CSU is the piece of equipment that provides the ones density requirement. On an AMI circuit it is normally referred to as "bit stuffing", "Jam bit 7" or simply "zero-code suppression". On a B8zs circuit it is called-- you guessed it "B8Zs" (Binary 8 zero-code substitution). Another clear channel code is ZBTSI. B8ZS and ZBTSI provide the ability to transmit zeros for data while continuing to meet the zero-code network requirement.

Yes, Your t1 will turn-up and run with out an external CSU. Many T1 cards in PBX's have internal CSU's, so don't require and external CSU. With no CSU on the line you are prone to frame slips and loss of sync. If the local telco finds trouble on their t1 spans because of a lack of a customer provided CSU could give them cause to disconnect the t1 until rectified.

Your Adtran CSU may look useless, but it provides a critical function in the t1 network.

So from what you’re saying the CSU ACE is not a sales gimmick but a real valuable piece of equipment.

Its just that the CSU ACE cost about 50% of the price of the T1 card in the PBX phone system. So if you buy 2 of them, it’s the same price as buying a spare T1 card in case one did blow out.

Let me ask you, how do you know if your T1 card has a built-in CSU ACE? Is there anyway to tell? Do you know which companies have this build in CSU ACE in the T1 card?

Thanks.

"Its just that the CSU ACE cost about 50% of the price of the T1 card in the PBX phone system."

That would be a very cheap T1/PRI card and probably in more need of a CSU. ACE CSU are dirt cheap compared to Kentrox CSU.

You can pick up used Ace's for about $75. Whether your T-1 card has a built in CSU depends on the manufactor. Nortel does. Some Avaya cards do. I can't speak for any of the others.

It's not a built in CSU ACE. Just a CSU. CSU stands for Customer Service Unit or Channel Service Unit, depending who you talk to. ACE is a product name. Look in the programming set-up for your T1 card and look for CSU emulation or something similar. The CSU provides protection to the network also.

Which ace can you buy for $75? I thought they were about $475?

Thanks.

You can get Adtran ACE CSU, non-display. Two on ebay going for $15 each right now. About a day left.

OK this may sound like a dumb question. Is there a standard log in for Smart Jacks like the Adtran H2TUR. I know you can use Procom but what settings do you have to change in order to login.
One of our local land line companies is telling me it is nnot possible to change the LBO on these cards and my equipment is not going to come into service until it is increased.
Thanks

The H2TU-R (HDSL 2-wire remote card) is Network terminating equipment. This card ends the regulated piece of the local circuit. It’s NOT a DSU/CSU and belongs to the Telco and should not be accessed by a non-regulated company’s technician…. That unit would be THE DEMARC in most cases.

The LEC person you spoke with must have been mis-informed (that’s a nice way for me to put it.) I suggest pushing back on them to change you LBO settings on the unit. The default setting is 0-133 ft. It can be set up to as far as 533-655 ft.

Again I’ll state, “THIS IS NOT A PIECE OF EQUIPMENT YOU SHOULD BE INTERFACING WITH!” … That being said, if I were in your position I’d change it myself too! :shhh:

Here’s a link to Adtran’s I&M pratice on the HDSL2 remote unit:
https://www.adtran.com/adtranpx/Doc/0/F5OGTS8PGEJ494J150A9PH2T2A/61223226L2-5A.pdf

Adtran NIU's are typically 9600, 8N1. You could place a CSU between the smartjack and your equipment, and set the LBO on the CSU to cover the distance.

Sorry to hi-jack this thread, but, I have tried to connect this CSU to Time Warners PRI interface & it does'nt work. If I plug it directly into the SBC smart jack, it works.
It must be a pin-out issue, but I have'nt had time to play with it.

How is Time Warner delivering their PRI? You might need to use a T1 crossover cable. T1 uses pins 1,2,4 & 5.

I am in agreement with Kyle. Ours here required a crossover cable. While it's true that you can get by without a CSU, we have had instances with video over PRI that failed miserably without the CSU being there. Maybe voice traffic is more tolerant than video?

I tried a cross-over cable...no dice...

We actually have this at our office. I still need to find the time to play with this, but, when I came across this at a customer site, I got a replacement and tried it at our office. Pins 1,2,4,5 straight from Time Warners channel bank to my NEC IPKI. When I put this CSU in between, no connection indication, when I plug it into the SBC smart-jack, I get connection indication...weird...

Every Time Warner Versa pack bank we have worked with required a flip of the pairs between the bank and customer premise equipment. No CSU in line.

I just recently completed a project for the feds. They did not purchase CSUs for their PRIs. I questioned this, but at that point they were unable to secure additional funds to add them to the job (if you've done fed gov't work, you know how that goes...)

When I tried to turnup the circuits, we were unable to get the D-channels to even come up. The ATT tech insisted it was because I didn't have a CSU between the smartjack and the switch.

I was skeptical because I've had other installations run T1/PRI without a CSU. Having a couple of the Adtran ACE in stock, I temporarily threw one up on the wall and bam! that PRI came right up. Take the CSU out and plug direct to the smartjack - no dice.

An ATT tech later explained it had something to do with the card in the smartjack and an issue with a lack of sufficent repeaters on the cicuit. The CSU regenerates the signal to the PBX maybe?

Hmmm. The feds telling you to not install a component that the FCC (the other feds) mandates.

CSU's are more than just a testing facility. They really do condition the field side of the circuit and tame it before it's presented to the CPE.

Sounds like everyone knows what a CSU is in the forum.

As a former 'Fed', let me assure that most agencies don't 'talk' to one-another. More on-topic however, most PBX systems I've encountered as of late have integrated the CSU function on their interface (program in s/w as DSX or CSU). That being said, most of them support signal regen capability only, and do NOT support loop-backs. Finally, I've seen references to the "legal" aspects - can someone be more specific? I believe this is a Part 68 issue?
Thanks,

jazwiner welcome to the board.
Please take note on the date of this thread and post by starting a new thread.
Thanks for your understanding and future cooperation.

I don't get why you say that??????? Why have many threads when you have one place to look for a related question? I am a gatekeeper in a boating forum, and I delete duplicate threads for that reason. I would rather read all the info in one thread then jumping to many threads.

It is also better for the people that want to help and offer good info, they don't have to repeat the answers they already gave.

I ask this question out of respect, or maybe to educate me on what I am missing.

Walter

Walter, we do discourage digging up old post unless you have something helpful and pertinent to the original topic. One reason so we don't get a bunch of stuff all thrown in one topic, which is why we try keeping things on topic as well. Also when the search feature is used it helps people find what they are looking for without sifting through a bunch of things that has one post on the topic and 15 not really relevant to the topic. We are also continually getting new brains and blood so a new better solution may have been found to an old problem and warrants a new start. Hope that explains it some.