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DID board locking up
- Thread starter IPhello
- Start date
Try reversing the polarity of a couple of pairs,and see if that takes care of it. Also, with a butt set, plug directly into one of the DID ports,a nd see if you can dial an extension number.There's not much to do with analog DID trunks, they generally work or they don't. You could verify with Telco, that your signalling is set up right as well.
Pepperzgm at gmail dotte comm
Pepperzgm at gmail dotte comm
- Thread starter
- #4
Pepperz,
We have done both of those things. Thanks
The odd thing is one of these sites had a legend before and it worked perfectly. One site is in Tampa, FL. and the other is in Birmingham, AL. it only happens about every 30 days. Reset the board goes away for 30 days happens again. Always on the first 2 ports, but if you move them around on the board the problem follows. I assume or would like to assume that it is software related since I do have 2 different service providers.
We have done both of those things. Thanks
The odd thing is one of these sites had a legend before and it worked perfectly. One site is in Tampa, FL. and the other is in Birmingham, AL. it only happens about every 30 days. Reset the board goes away for 30 days happens again. Always on the first 2 ports, but if you move them around on the board the problem follows. I assume or would like to assume that it is software related since I do have 2 different service providers.
When you say the trunk locks up, what do you mean? Is it held off-hook in a siezed condition or does it stop taking calls??
You also mentioned that the 'problem' follows the telco DID trunk you move around. That tells us right there that the trunk has a problem.
If that is the case you need to open a trouble ticket with your service provider.
Now analogue DID trunks are POLARITY SENSITIVE so you need to maintain tip/ring orientation. This could be part of your problem. I would not indiscriminately go around reversing T/R leads unless you suspect that is a problem with a specific trunk. Some DID trunks will work for a short period of time when they have a reversal, but then the switch will take them out-of-service. Hence no more calls. When you have a reversal toward the switch it busies out the trunk.
If you open a trouble ticket the tester or repair person can test the trunk to verify the polarity at their switch or test panel in the CO.
Hope this helps!
....JIM....
You also mentioned that the 'problem' follows the telco DID trunk you move around. That tells us right there that the trunk has a problem.
If that is the case you need to open a trouble ticket with your service provider.
Now analogue DID trunks are POLARITY SENSITIVE so you need to maintain tip/ring orientation. This could be part of your problem. I would not indiscriminately go around reversing T/R leads unless you suspect that is a problem with a specific trunk. Some DID trunks will work for a short period of time when they have a reversal, but then the switch will take them out-of-service. Hence no more calls. When you have a reversal toward the switch it busies out the trunk.
If you open a trouble ticket the tester or repair person can test the trunk to verify the polarity at their switch or test panel in the CO.
Hope this helps!
....JIM....
- Thread starter
- #6
Thanks Syquest,
When I say the trunk locks up, I mean that they just stop taking calls. RNA. I put in a ticket earlier with the service provider to monitor the lines. They had already been out to check everything and said they tested good to equipment. I realized the polarity sensitivity already. Also, We are going to check to make sure we have a good ground. These were suggestions by Avaya since it only happens every 30 days or so.
When I say the trunk locks up, I mean that they just stop taking calls. RNA. I put in a ticket earlier with the service provider to monitor the lines. They had already been out to check everything and said they tested good to equipment. I realized the polarity sensitivity already. Also, We are going to check to make sure we have a good ground. These were suggestions by Avaya since it only happens every 30 days or so.
I had an issue with the Analog DID. I made 3 trips out until the problem actually occured. Somehow there was an Incompatibility with the CLEC Channel bank and the Legend DID card. The issue was with the wink. Somehow the DID card wouldn't recognize the wink coming from the CLEC when the call would be coming in. Again, just like you when a system reset would happen, the card would stop recieving calls. We changed the signaling to immidate start and I never heard a call back from them again. Of course, we were not getting a RNA, when the card would stop recieving calls, the would recieve a fast bust from the CLEC. Hope this helps.
- Thread starter
- #8
A few more points to keep in mind, intermittent winks can be a cause of a DID trunk going out-of-service. This can be caused by faulty wink timing or a defective channel unit in the CO. (Channel units do go bad).
Winks can be mutilated by wierd loop loading and the lack of a Solid System Ground. Now the wink timing can be adjusted in the Legend I believe. Its value is in milliseconds(ms). Typically the time window is 300 to 600ms. If this is the issue, try increasing it to 400ms or 450ms.
When DID trunks are provisioned analogue, they still come from the switch as digital, then they become analogue at the channel bank. All trunking in CO switches comes out on DS1 facilities on all modern switches like the 5ESS or the DMS100. They are then terminated on a channel bank and use a DPT channel unit (Dial Pulse Terminate) to connect to the cable pair out to the customer's premises. DID trunks or 2-wire loop trunks are the simplest form of trunking.
....JIM....
Winks can be mutilated by wierd loop loading and the lack of a Solid System Ground. Now the wink timing can be adjusted in the Legend I believe. Its value is in milliseconds(ms). Typically the time window is 300 to 600ms. If this is the issue, try increasing it to 400ms or 450ms.
When DID trunks are provisioned analogue, they still come from the switch as digital, then they become analogue at the channel bank. All trunking in CO switches comes out on DS1 facilities on all modern switches like the 5ESS or the DMS100. They are then terminated on a channel bank and use a DPT channel unit (Dial Pulse Terminate) to connect to the cable pair out to the customer's premises. DID trunks or 2-wire loop trunks are the simplest form of trunking.
....JIM....
IPhello,
I would vote for the wink being the problem, however if I read your post correctly, the people calling in get a RNA? If the DID is not working correctly, it shouldnt pass digits to the Merlin and the calling party should receive either a fast busy or a telco intercept message not RNA since the Merlin provides all progress tones that the calling party hears.
Vince
I would vote for the wink being the problem, however if I read your post correctly, the people calling in get a RNA? If the DID is not working correctly, it shouldnt pass digits to the Merlin and the calling party should receive either a fast busy or a telco intercept message not RNA since the Merlin provides all progress tones that the calling party hears.
Vince
Well, here's another thought.
What is your "INVALID DESTINATION" setting in the Legend?
If it is being sent to something that doesn't have a phone or a mailbox attached, then your RNA could be coming from a "NEVER NEVER LAND" location in the Legend, if something is dialed that "jumps the track" from your dial plan.
I would look at that.
What is your "INVALID DESTINATION" setting in the Legend?
If it is being sent to something that doesn't have a phone or a mailbox attached, then your RNA could be coming from a "NEVER NEVER LAND" location in the Legend, if something is dialed that "jumps the track" from your dial plan.
I would look at that.
Another item to consider with traditional wink DID analog trunks is the type of signaling involved. You have two types "dial pulse" and "DTMF" (tone)outpulsing. If you have a channel bank, make sure that all the channel cards are provisioned the same (DTMF is preferred). And make sure your switch is provisioned the same.
If memory serves, a switch provisioned for "DTMF" will also accept "DP". Also verify that the "wink" timing is the same on the channel bank and the PBX, (300ms is preferred)but you must match what the channel bank is using, if it is not adjustable.
If memory serves, a switch provisioned for "DTMF" will also accept "DP". Also verify that the "wink" timing is the same on the channel bank and the PBX, (300ms is preferred)but you must match what the channel bank is using, if it is not adjustable.
There are actually three types of outpulsing on DID trunks. The third is MF which was available before DTMF was back in the days before end office DID became popular in Paging and IMTS mobile.
In reference to WINK timing, it is the device sending the WINK that controls its timing. Channels Units (DPT or DPO or 4W-E/M) don't provide any 'wink' control as far as setting any kind of parameters to adjust. They repeat what they receive and in the conversion of analogue to digital, the WINK is just toggling the A and B signalling bits on and off. But conditions of the copper loop can influence the way it operates and responds and can affect timing.
You are absolutely correct about DID trunk circuits of PBXs or other types accepting both DP and DTMF. That is because of its design, 2-wire loop trunks were always DP. The loop trunk was the first kind of office trunk that ever existed in the early step-by-step days, and even # 1ESS had 2-wire loop trunk circuits. But on the 5ESS switches there are none. All trunking is provided at the DS1 level. So in order to provide analogue DID service they are terminated on channel banks in the CO using DPT channel units connected to the local loop plant.
....JIM....
In reference to WINK timing, it is the device sending the WINK that controls its timing. Channels Units (DPT or DPO or 4W-E/M) don't provide any 'wink' control as far as setting any kind of parameters to adjust. They repeat what they receive and in the conversion of analogue to digital, the WINK is just toggling the A and B signalling bits on and off. But conditions of the copper loop can influence the way it operates and responds and can affect timing.
You are absolutely correct about DID trunk circuits of PBXs or other types accepting both DP and DTMF. That is because of its design, 2-wire loop trunks were always DP. The loop trunk was the first kind of office trunk that ever existed in the early step-by-step days, and even # 1ESS had 2-wire loop trunk circuits. But on the 5ESS switches there are none. All trunking is provided at the DS1 level. So in order to provide analogue DID service they are terminated on channel banks in the CO using DPT channel units connected to the local loop plant.
....JIM....
Syquest you are absolutely correct, I am making a broad assumption that since this is a Magix 4.0, it is using newer equipment and that the carrier is providing service also using equipment of a newer vintage, ie: an Adtran channel bank which has some conversion capabilities, but may have been cobbeled together from parts and may not have been correctly reprovisioned when installed. I have seen this more than once, and have had to retranslate the bank myself. Timing, signaling, and polarity are the three most important issues on a DID circuit, as I am sure you will agree.
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