Off Hkvdc(Min); Procedure To Set Off Hkvdc(Min) Threshold - AMERITECH AM8a Instruction Manual

AM8a Instruction Manual
4.11.2 OFF HKvdc(min): This parameter sets the threshold the AM8a uses to determine OFF
HOOK status when it is configured to ANALOG(loop). The dc voltage present across
the Tip and Ring leads must fall below this threshold (towards zero, regardless of
polarity) before the AM8a will recognize an OFF HOOK condition. This threshold will
also affect the ability of the AM8a to detect dial PULSE digits. The next sub-section
provides the procedure to determine the best setting of this parameter.
4.11.3 Procedure to Set OFF HKvdc(min) Threshold: The on/off hook threshold TO voltage
must be carefully set to ensure the AM8a correctly recognizes ON and OFF hook
events. The setting may have an effect on the operation of the PULSE digit analyzer,
since PULSE dialing is accomplished by opening and closing of the loop. (ON/OFF-
HOOK).
A quick way to determine the setting of what voltage to set the threshold voltage is to
use the METER DISPLAY as follows (refer to sub-section 6.4):
1. When the LINE/TERM equipment is ON HOOK, measure the Vt–r dc. This voltage
should be equivalent to the battery supply of the switching equipment.
2. Go OFF HOOK with the LINE/TERM equipment and again measure the Vt–r dc.
This voltage will indicate the OFF HOOK voltage and should be the minimum
voltage encountered under normal operation.
3. Now set the OFF HK vdc(min) parameter for a voltage between the two measured
voltages.
0037-S04.L_32
(18-0037)
4-9
Analysis Parameters
February 10, 2000