Xylem H-264 - Manual (Page 9)

ASI v2 Operations (PRELIMINARY)
discarded. Potential fatal error conditions include: battery voltage falling below the battery
voltage cutoff threshold just prior to or during transmission; or internal software error conditions.
Test Input
A switch input is available which causes a test transmission. On switch contact opening, a
single ALERT message is transmitted, with a factory set ID value of 5000 and a data value
which increments on each on each contact “break”. This test input is not buffered, and multiple
occurrences during a transmission and duty cycle wait period are treat as a single “break”
occurrence. Note - during a test input transmission only a single serial input buffer is in
available to buffer any incoming serial data.
Power, mechanical
The ASI is designed for a 12V battery/solar power supply. The minimum supply voltage for the
ASI board alone is only 4 volts, but most transmitters require a minimum of 9 volts. The ASI
board maximum input voltage is 20 volts, but commonly, transmitters have an 18 volt maximum
input voltage specification. (The ASI printer circuit board is designed to optionally allow a
transmitter to be powered from a separate battery/supply from the ASI itself: contact the factory
for assistance in configuring the ASI for split supplies.)
The ASI monitors the battery voltage by averaging eight 315 microsecond analog to digital
converter samples of the battery voltage prior to turning on the transmitter, and every 2.5
milliseconds during transmission. If the battery voltage falls below the minimum transmitter
battery voltage cutoff, the transmitter is turned off and the error processing state is entered.
The threshold is factory set at 9.00 volts (8.92 to 9.08 volts over temperature).
A green LED indicates that the Switched+12 volt supply is turned on, and a red LED indicates
that PTT is on.
Typical current consumption is 9 microamps waiting for serial input. During message parsing
and processing, typical current consumption is 323 microamps. During high speed processing
(ADC operation, digital FSK tone generation) the current consumption is typically 2.8 milliamps,
and with the Switched+12 volt LED on, the PTT LED on, and the 3 rd order audio filter on, the
typical current consumption is 10 milliamps.
The ASI is 10.0 cm x 6.20 cm. There are four (0.381 cm diameter) mounting holes. All 4
located 0.40 cm on center from the long top and bottom edges; 2 are located 0.4 cm on center
from the right narrow edge and the other 2 are located 2.0 cm on center from the left narrow
edge.
The 2 pin input battery and 4 pin transmitter screw terminal connectors are located along the left
narrow edge. The 4 pin serial input screw terminal connector, 2 pin test input header and 4 pin
AuxRS232 header are located along the right narrow edge.