User's Manual

905U-K.MAN Rev. 1.1 January 2002
 ELPRO Technologies Pty Ltd Page 31
The sample time is the time
period for each analogue
input measurement.
Between measurements, the
905U-K will operate in
"sleep" mode. When the
sample time has expired, the
905U-K will turn on the
analogue loop power
supply. After a further
time, called the warmup
time, the 905U-K will
make a measurement of the
input. The warmup time allows the transducer to stabilise and become accurate after the loop
supply is turned on.
The sample time may be entered in minutes, between 1 and 30 000 minutes. If a zero value is
entered, then the loop power supply will be always on. The warmup time may be entered in
seconds between 1 and 127 seconds. If a zero value is entered, then an analogue measurement
will be made as soon as the loop supply is turned on. If both the sample time and warmup
time are set to zero, then an analogue measurement will be taken on every 905U-K cycle
(every 0.5 sec).
4.5 Analog Setpoints
A high setpoint value and a low setpoint value may be entered. The internal setpoint status is
determined by these values in comparison to the analogue input value. If the analogue input is
less than the low setpoint,
then the setpoint status is
"on". If the analogue input
is more than the high
setpoint, then the setpoint
status is "off". When the
input is between the low
and high setpoints, then
the setpoint status remains
unchanged.
The setpoint values may be
set between 0 and 100%
corresponding to 0mA and
20mA. The low setpoint
may be set to the same value as the high setpoint, however the low setpoint should not be set
to a higher value than the high setpoint.
4.6 Pulse Inputs
There are several configurable parameters for pulse inputs. The debounce value can be
adjusted from the Unit Details selection, as per Digital Inputs.