User`s guide

9(18)
Datum/Date Rev
Dokumentnr/DocumentnrUppgjord/Prepared
Dokansv/Godkänd - Doc respons/Approved Kontr/Checked Tillhör/Referens-File/Reference
99-07-15 D
141/155 34-ASB 150 02 Uen
FACILITY DESCRIPTION
Faktaansvarig - Subject responsible
In case of a high counter value indication, the cost unit
is redefined, so that the number of characters does not
exceed the available characters on the display and
printout. (The following table uses "ATS“ as
abbreviation for a local currency.)
1 Kilo ATS = 1 KATS = 1,000 ATS
1 Mega ATS = 1 MATS = 1,000,000 ATS
1 Giga ATS = 1 GATS = 1.000,000,000 ATS
Limit for cost counter
In practice, the counter will hardly ever overflow.
However, the accuracy of the counter decreases if the
counter value indication for trunks or callers is already
very high. If this is the case, it will not be changed by a
cheap call.
In order to guarantee accuracy, you may determine a
limit for the cost counter. If the limit is reached, the
user receives an alarm.
The alarm indicates that the demanded accuracy is
exhausted and that it is recommended to print (or read
out) and cancel the counter. (The costs are further
accumulated if the costs of individual calls may be
gathered by the cost counter.)
The formulas below offer two approaches for definition
of the cost limit.
• Formula for calculating the limit.
Define your minimum requirements for the
accuracy of the counters and use the formula for
calculating the maximum cost limit.
• Formula for calculating the accuracy.
Define the requested cost limit (e.g. based on av-
erage cost per month) and check, whether this
cost limit gives you appropriate accuracy. Use
the formula for calculating the accuracy for this
check.
For calculation of the limit we use a formula containing
the following variables:
L cost limit for cost counter
Cmin costs for the cheapest chargeable call
A accuracy of cost display (e.g. 0.01
corresponds to an accuracy of 1 %)
Formula for calculating the limit
Given: the costs for the cheapest chargeable call Cmin
and the requested accuracy of the cost counters A.
The cost limit is calculated by the following formula
L = 360 10
6
* Cmin * A
Example:
The cheapest chargeable call costs 0.80 ATS
(= Cmin). The requested accuracy may be 1 %
(A = 0.01). What is the maximum limit of the cost
counters?
L = 360 10
6
* 0.80 *0.01 = 2,880,000
Result: the cost limit shall be < 2.88 million ATS.
Formula for calculating the accuracy
Given are the costs for the cheapest chargeable call
Cmin and the requested cost limit L.
The accuracy of the cost counters is calculated by the
following formula
A = L / (360 10
6
* Cmin)
Example:
The cheapest chargeable call costs 0.80 ATS
(= Cmin). The requested cost limit is 100,000 ATS
(= L). What is the accuracy of the cost counters A?
A = 100,000 / (360–10
6
—0.80) = 0.00035
Result: the accuracy of the cost counters at reaching
the limit is at least 0.04 %.