Mitel SX-200 Documentation page 488

All lines originating trunk calls are DTMF and require tone-
to-pulse conversion.
All originating trunk calls involve one digit to get an outgoing
trunk, a 1 second wait, then seven digits. The receiver is seized
on origination and is held until 10 seconds after the last digit is
punched.
All stations have 4-digit numbers.
l
A receiver can interpret either DP or DTMF.
Receivers are provisioned in groups of two.
l
There is no delay in connecting an idle receiver to an originat-
ing line.
12.07 With the foregoing assumptions and under the following con-
ditions, the required quantities of receivers are as shown in
Table 12-2:
Cases of 40, 80, 120 and 160 line PBXs
l
Degrees o f Intercom Traffic expressed as 0, 10, 20, 30, 40 a n d
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50 percent of Originating Traffic.
12.08 Tables 12-3 to 12-6 inclusive, show quantities of receivers
required under particular traffic conditions, for differing quan-
tities of installed lines and trunks and proportions of Intercom Traffic.
The information in these Tables have been derived from the traffic
calculation formulas shown in Appendix A.
DTMF Generator
Provisioning (SX-200)
12.09 Two DTMF generators are provided on the Tone Control card.
The probability of a generator being available for use within 1
second after initiation of a call is calculated to be 0.996. This probabil-
ity is calculated for the following assumptions, with the calculations
detailed in Appendix A.
Traffic: 5.55 ccs/line
l
38 % outgoing
180 s average holding time
Installed stations: 140
DTMF pulse times: 75 ms on/75 ms off
Average number outpulsed digits: 11.
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