Time-Of-Use Registers; Demand Registers; Tou Maximum Demand Registers - Elster A1140 User Manual

11.1

Time-of-use Registers

A total of 8 Time-of-use (TOU) registers are provided. Each TOU register has a single source that
can be selected from one of the following:
Import kWh
Export kWh
Q1 kvarh
Q2 kvarh
Q3 kvarh
Q4 kvarh
kVAh 1
kVAh 2
Customer Defined Register 1
Customer Defined Register 2
Each TOU Register is independently time controlled so that registration can take place over a
restricted time period.
The contents of each TOU Register can be viewed on the display along with the active rate(s).
11.2

Demand Registers

The A1120/40 provides the rising demand value associated with each of the 10 registered
quantities specified in Section 11.1. The demand integration period can be 1, 2, 3, 4, 5, 6, 10, 15,
20, 30 or 60 minutes.
In A1140 meters the integration period used for the demand registers is the same as the load
profile integration period.
During any period, the rising demand value is calculated by measuring the energy consumed to a
point in a period, then scaling the measured value by a factor equal to the ratio of the demand
period to a total hour interval.
Rising Demand = Energy recorded in current period x
The contents of each Rising Demand Register can be viewed on the display.
11.2.1

TOU Maximum Demand Registers

The meter has 4 maximum demand registers, each with an independent source selectable from
one of the 10 rising demands.
The meter records the three highest maximum demand values (along with time and date stamp)
that can be sampled on a continuous basis (24-hour period) or over a restricted time period.
At the end of each billing period, the greatest of the three demands is added to a corresponding
cumulative maximum demand register.
The maximum demand registers are then set to zero.
Operating & Maintenance Instructions
60
minutes in demand period
15
p