Inter-Tel AXXESS Manual page 306

Installation
® ®
INTER-TEL AXXESS
LGC and LGC-D Modification
10.31 Under certain conditions, previous versions of the LGC (part no. 550.2309) and the
LGC-D (part no. 550.2310) were not able to always properly detect the "ground start" signal
provided by the central office (CO). A modification to the LGC and LGC-D has been imple-
mented to correct this problem.
10.32 More specifically, the previous versions of the LGC and LGC-D did not function prop-
erly in ground-start mode when terminated on a CO trunk that had a constant current battery
feed of less than approximately 25mA. The new cards have a built-in 50VDC power supply
and therefore no longer rely on the current from the CO to detect the "ground start" signal.
Problem Identification
10.33 A customer site may have this problem if a phone user's display shows "LINE IS
UNPLUGGED" when attempting to access a ground start trunk on an LGC or LGC-D. To
determine if the card really does have a problem detecting the ground start signal from the CO,
follow these steps:
1.
2.
3.
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MANUAL VERSION 11.0 – May 2008
Ensure that the appropriate trunk circuit on the card is programmed for ground start
mode. (Loop start mode is not subject to this problem.)
Verify that the card is properly installed and connected.
Verify that tip and ring for the trunk circuit are properly connected. Below is a simple
method that works for most cases:
At the associated CO block, remove the bridging clips for the trunk.
a.
On the telco side of the block, attach a test set (butt set) in monitor mode (on-
b.
hook) to tip and ring.
Apply ground to the ring terminal.
c.
If you hear dial tone (only while ground is applied), tip and ring are properly con-
d.
nected. Replace the bridging clips and check to make sure the card can still
receive dial tone.
If you do not hear dial tone, apply ground to the tip terminal. If you now hear dial
tone, tip and ring are reversed.
NOTE:
Be sure the test set is in monitor mode. If it is in off-hook mode, sometimes
the line can be seized regardless of the polarity, and the test is invalid.
LGC and LGC-D Modification