User Manual

Table Of Contents
Specifications B-1
SmartPoint Module for the Elster A3 Meter ECMTM40000
Appendix B Specifications
B.1 External AC Line Power
DC Supply A: 13 VDC +/- 1V, 150mA max
Maximum Message Duration: Supported by supply capacitor, 200 ms
B.2 Current Consumption
The end point device shall have three modes of operation and a different current requirement for each.
Quiescent Mode: Normal quiescent state. Entered during periods of no input or reading activity to
charge capacitor, microprocessor and local high speed crystal always running. The TCXO and other
peripherals are off in this state. In this state an additional 9 mA is available for charging the transmit
capacitor. I
Charge
6 mA @ the 36 V rectified voltage source.
Receive Mode: (Optional) A duty cycled state entered to detect if an incoming message is occurring,
and, if so, to receive that message. I
Receive
25 mA @ the 3.3 V supply.
Pre-Transmit Mode: Before transmission, the uC powers up TCXO, Synthesizer, VCO, and other RF
circuitry before actively transmitting. The current consumption in this mode will be I
Pre-Transmit
30
mA @ the 3.3 V supply.
Transmit Mode: Entered when on air transmission is required. I
Transmit
850 mA @ the 3.6 V
switching regulator.
B.3 Power Failure
Power Fail Transmission: Following power failure, as detected by a Power Failure IRQ signal from
the iCon display board, the processor shall place the endpoint device into a low power mode until a
programmable time limit up to 120 seconds (Outage Time Threshold). During this time, the device
shall count the number of pulses on the Power Failure IRQ line and keep this information to report in
an Alarm Message to report the outage. Once the Outage Time limit has been reached, the device
shall wait an additional pseudo-random time (up to 152 seconds), at which time it shall transmit an
Alarm Message.
Power Restored Detection: Once power has been restored (as determined by no Power Fail IRQ
signals being sent by the iCon and the Minimum Voltage Level being exceeded) for longer than the
Power Restored Time Threshold, the device shall wait an additional pseudo-random time (up to 160
seconds) at which time it shall send an Alarm Message indicating Power Restored.