Optional Rs232 Port; Modem Power Supply; Resetting The Power Supply; Data Stream Mode - Elster A1140 User Manual

16.2

Optional RS232 Port

An RJ11 connector provides RS232 communications. The port allows access to the same data as
the optical port, using the same protocol. The port operates at speeds of up to 9600 baud. Data
Stream Mode (See Section 16.3) allows a fast method of retrieving all data.
The RS232 port supports multi drop mode, allowing up to 10 meters (RS232) or 32 meters
(RS485) to be accessed from a PC (See Appendix B).
16.2.1

Modem Power Supply

The RS232 port allows different modules to be added that can support different means of
communications (PSTN, Ethernet, GSM etc).
An isolated internal d.c. supply to power the modem is provided via the RJ11 socket
Nominal Voltage: ≥+6V with mean load ≤500mA
The power is sufficient to support a GSM modem
16.2.2

Resetting the Power Supply

If a modem is installed which draws too much power from the meter, a transient reset occurs and
the modem power supply is disabled to prevent continuous resetting of the meter. On early
versions of A1120/40 meter only, the RS232 port may also be disabled. The power supply (and
RS232 port on early versions of the meter) can be re-enabled using the PMU via the IEC 1107
port or by using the following sequence:
Step to the 'GSM signal strength' display in the Utility Display section of the meter
Press the display and utility pushbuttons together for several seconds until 'PSU On' is displayed
If the meter generates another reset, an alternative modem should be fitted and the power supply
re-enabled as above.
16.3

Data Stream Mode

Data stream mode allows fast reading of all metering data (90 days of 30 minute, one channel
data in 30 seconds). To achieve this, the meter and modem device must be configured to 8 bits,
no parity, 1 stop bit (Selectable via the Power Master Unit).
Operating & Maintenance Instructions
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