Troubleshooting Ringing Generator Problems - Nortel DMS-100 Series Maintenance Manual

12-8 Advanced troubleshooting procedures
4. If LSGs 10 through 19 do not have dial tone, verify with a voltmeter that
5. If you do not have dial tone, contact the next level of support.
6. This procedure is complete.

Troubleshooting ringing generator problems

One or both ringing generators (RGs) can fail. The LEDs on the 6X30 RGs
can illuminate. To isolate and correct the problem perform the following
procedure:
1. Replace the RG first.
2. Remove the RA and RB fuses one shelf at a time and observe the LEDs.
3. Busy one unit at a time. Unseat the 6X51, 6X52, and 6X53 cards and
4. Reseat the cards in the troubled unit. Remove the fuses for each drawer
5. If you remove all the fuses and the cycling does not stop, more than one
297-8361-550 Standard 04.01 September 2000
This voltage is the talk-battery supply for these drawers and comes from
the power distribution center (PDC) for this frame. Check the fuse in the
PDC if the voltage is not available.
TB1 lug 8 reads -48V. This voltage is the talk-battery supply for these
drawers.
Note: When you power-down a RG, the system removes the associated
OPM unit from service. When you power-down RG-0, the system
removes unit 0 from service.
The RA fuse supplies ringing to the even-numbered subgroups for the
specified shelf. The RB fuse supplies ringing to the odd subgroups for the
specified shelf.
If the LED disappears when you remove a fuse, proceed to step Item 4,
"Reseat the cards in the troubled unit. Remove the fuses for each drawer
in the shelf. Make sure you pull all three fuses (5 V, 15 V, and 48 V) for
the drawer. If the cycling does not stop, replace the fuses for the drawer.
Proceed to the next drawer until the cycling stops." on page 12-8. If the
LED stays, proceed to step Item 3, "Busy one unit at a time. Unseat the
6X51, 6X52, and 6X53 cards and watch for the cycling to stop. This
action isolates the trouble to the unit. Replace the 6X51, 6X52, AND
6X53 cards." on page 12-8.
watch for the cycling to stop. This action isolates the trouble to the unit.
Replace the 6X51, 6X52, AND 6X53 cards.
in the shelf. Make sure you pull all three fuses (5 V, 15 V, and 48 V) for
the drawer. If the cycling does not stop, replace the fuses for the drawer.
Proceed to the next drawer until the cycling stops.
drawer is defective. In this event, remove all fuses for all drawers in the
shelf at the same time. Replace the three fuses for each drawer and note
when the cycling starts.