sundance-communications.com/forum Forums TDM Business Telephone Systems Samsung Telephones & Systems SVM-400 Not detecting a caller hang up

I have a Sumsung DCS-816 system set up and have purchased a SVM-400 unit which i have connected to extension ports 209 and 210.

Put the SVM-400 to group 503

Set Trunk Ring (MMC xxx) to Day:503 Night:503

It works fine when a caller calls, they are greeted and the transferred to the operator group 500.

The only problem is if the caller hangs up before the call is answered by our operator group, even though the caller has hung up the phones still keep ringing, when answered obviously there is nothing there!

Im sure there is some setting to detect a hang up by the caller?

Anyone able to help?

Regards,
Ashley

Please do not post MMC's in this forum,thank you.

Check your disconnect supervision on the lines.

Hi

Where would i find the disconnect supervision?

ive currently got the SVM-400 plugged into the 9th and 10th DLI port (extensions 209 and 210)

i read it should be connected to a SLI port, does this mean i need to install an SLI card into my system?

Disconnect Supervision is provided by the carrier, so you will need to contact them.

I'm not sure if it's called CO Disconnect on your side of the pond. CO Disconnect is sent by the carrier when the caller hangs up and it tells the phone system to drop the call.

If you are using standard BT analog lines these do provide a end-of-call signal but it is fairly short - between 90 and 130 mSec as detailed in SIN351 section 7 <https://www.sinet.bt.com/351v4p5.pdf>

I believe you can ask BT to increase this, but trying to navigate their customer support to someone who knows about this can be difficult, so in the past I've reduced the CO SUPV TIME in TRUNK-WIDE TIMERS MMC as the default is 400 mSec so the 816 fails to see the signal.

ive changed the CO SUPV TIME to 0100 MSEC but it still keeps ringing when the phone has been put down!

All the adjusting in the world will not make a difference if the "end of call" signal is not there. You will need to get your telco or your system tech to check this for you.

i rang BT up and asked them to set the Loop Disconnect Timer to 800 mSec as i read it in another thread on here, just waiting for them to carry the work out now, they said it should be done by tomorrow.

hopefully it will work!

BTW when the SVM-400 is turned off the phone rings and disconnects fine, it just when the caller goes through the SVM-400 it doesnt disconnect! is it because the calls is being TRANSFERED from the SVM-400 to the operator group, in theory its not connected to anything, its trapped in the system?!?

otherwise do you think i should go down the ISDN route?

FYI against one of your previous notes.. the SVM gets connected to DLI ports, not SLI ports...( i can't say for sure but hooking them up to SLI ports may damage your SVM)