Multi-Tech Systems 7500 - Manual (Page 293)

ION 7500 / ION 7600 User’s Guide Availability on the Meter Front Panel
Power Availability Technical Note Page 293
Availability on the Meter Front Panel
The following power availability values display on the meter’s front panel, and are
viewable in the Vista™ component of ION Enterprise™ or ION Setup™ software:
Number of Nines: the number of consecutive nines that appear in the most-
significant digits of the availability value (e.g. “10” on the front panel indicates
10 nines: 99.99999999).
Availability-ppm: the fraction of time that the power is available, in parts per
million (ppm).
Evaluation Time (days): the number of days that have elapsed since the
calculation was last reset. This gives an indication of the time interval over
which the availability calculation is made.
The availability framework is found at this location within Designer: Advanced
Setup\Power Quality Framework\Power Availability Framework.
Sample Availability Framework Behaviors
Scenario 1: blade powered meter + power system outage
The Sag/Swell total disturbance time includes the outage. The meter downtime
from the diagnostics module is added to the meter uptime to account for the total
time of observation.
Scenario 2: blade powered meter + meter decommissioned
The Sag/Swell module logs the downtime as disturbance time. When the meter
powers back up, the meter downtime from the diagnostics module is added to the
meter uptime.
Scenario 3: auxiliary powered meter + power system outage
The Sag/Swell total disturbance time includes the outage. The meter never loses
power, which means that there is no meter downtime and the meter uptime is
equivalent to the total time of observation.
Scenario 4: auxiliary powered meter + meter decommissioned
The Sag/Swell module does not log a disturbance time. When the meter powers
back up, the meter downtime from the diagnostics module is added to the meter
uptime.
Assumptions
The above scenarios assume that:
1. The auxiliary powered meter assumed the power system was within specs
during a meter down time if it didn't detect a disturbance prior to powering
down.
2. The Sag/Swell module is configured correctly to monitor voltage disturbances.
3. The Sag limit is set above the voltage level at which the meter starts powering
down.