PRACTICE 553-2201-183
p
LIMITATIONS
4
POWER
REQUIREMENTS
Page 4-4
4.10 The maximum number of Ringers that can be connected to
DN loop is shown below:
MAXIMUM NUMBER OF RINGERS
LOOP
QPC452lQPC494 QPC594/QPC789
RESISTANCE
QPC521/QPC558 -QPC729
1000
2
850
3
i
600
i
4
350
4
Note:
Loop resistance excludes impedance of telephone sets.
4.11
Supervision limitations are given in Table 4-B.
4.12 To maintain transmission quality, the following shows
each
the
. .
maximum number of Voice Calls (number of telephone sets off-nook
on the same
DN)
recommended:
QPC452lQPC494 QPC5941QPC789
QPC521/QPC558
QPC729
RESISTANCE
(OHMS)
17ma
20ma
17ma
20ma
up to
40 21
41
to
100
;
1
;
1
101
to
250 2
1
1
251
to
1000
11
:
1
Note 1:
Loop resistance exclttdes impedance of telephone sets.
Note 2:
17ma/20ma
is the current that a typical telephone set
requires in an off-hook condition.
4.13 The QPC452, QPC521, QPC681 and QPC682 packs have the
following typical power requirements:
VOLTAGE IDLE CURRENT ACTIVE CURRENT
ImA) (mA)
+2.5
V,
*00.5%
<O.l <O.l
+6
V,
kl%
50
140
-6V,
+l%
50 140
-48 V,
f3%
320
-f-52
V,
+4%
:
85