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Measurements
The meter measures instantaneous consumption and can calculate demand using various
methods.
Peak demand
Peak (or maximum) demand is the highest demand level recorded over the billing period.
Power utilities generally bill commercial customers based on their peak usage levels, called peak
demand (in kW) and energy consumption (in kWh). Peak (or maximum) demand is the highest
demand level recorded over the billing period. You can view peak demand values on your meter's
display.
Your meter calculates the average current demand and kW, kVAR and kVA demand using sliding
window demand methods. It supports coincident demand values when a peak demand is
detected.
Your meter's default configuration is suitable for most applications, or you can customize it for
your specific application. You can configure the minimum time between consecutive demand
resets.
NOTE: If not specified, references to demand are assumed to mean power demand.
Peak demand reset lockout
The demand reset lockout time sets the minimum time allowed between consecutive demand
resets; the meter ignores any attempts to reset demand that occur within the lockout period.
The peak demand reset lockout period is user-configurable (typical default value is 25 days).
See the ION Setup online help for instructions on how to configure demand peak and the demand
reset lockout period on your meter.
See ION Reference, available from www.usa.siemens.com/pds, for detailed information on how
Sliding Window Demand modules measure and calculate demand values.
Sliding window demand
To calculate demand values, your meter uses the sliding window averaging (or rolling interval)
method which divides the demand interval into a set number of subintervals of specified duration.
The demand is measured based on the average load level over the most recent set of
subintervals. Sliding window demand also provides predicted demand values.
Examples of sliding window demand
This example shows two different ways of configuring a 15-minute demand interval:
• Single interval (also called block or timed block): the 15-minute demand interval is defined as
a single subinterval with a duration of 15 minutes.
• Sliding window (also called rolling block): the 15-minute demand interval is defined as three
subintervals with a duration of 5 minutes each. This method offers better response time than a
single interval.
Single interval (block)
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9410 series - User manual
7EN05-0336-09
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Troubleshooting
