User's Manual

Universal Metering Transponder for kV2c™ Meter User Guide 23
Chapter 2 • Functional Description
Meter Constants
The UMT-C-KV can store and communicate required meter values when those
values are programmed in the meter and are mapped to a register in the
UMT-C-KV. Values may include, but are not limited to: VT ratio, CT ratio, meter
constant/Kh value, number of dials, meter type, etc.
This allows the TWACS Master Station to automatically capture this information
for billing without additional manual data entry.
For example, in the kV2c meter, the Total Consumption in numeric kWH values is
captured in the appropriate metering register and then retrieved by the
appropriately mapped transponder registers and relayed to the Master Station per
scheduled or on demand requests.
Demand Measurement
The UMT-C-KV is configured to perform Demand Metering by reading
demand-related values from the kV2c meter’s ANSI Standard Table 23 and 63.
The UMT-C-KV can retrieve these values from the appropriately mapped meter
registers. These locations can be mapped to any available Meter Map Register,
except for Meter Map Register 1, and 3 through 7.
Demand Reset
The Demand Reset command instructs the UMT-C-KV to execute a Demand
Reset. This operation updates Meter Data registers, but only if the 255-minute RCE
Demand Lockout Time is expired. The lockout period is based on the Time/Date
Stamp of the last Demand Reset.
When a Demand Reset command is issued, the RCE checks for the presence of a
lockout condition and if none exists:
• Updates the Meter Data Registers
• Sends the meter a Demand Reset command
• Shifts the newly populated Meter Data Registers to the Historical Data
Billing Shift registers
• The actual date and time of this shift is captured in Actual Shift/Reset
Timestamp register #335
The 255-minute RCE Demand Lockout Time prevents an unwanted demand reset
when the UMT-C-KV receives a Demand Reset retry. The timer is nonvolatile and
evaluates the 255-minute lockout at power-up. If a RCE Demand Lockout is in
effect, a demand reset will not occur. If a shorter lockout time is selected for the
RCE, the 255-minute lockout time supersedes the shorter value.