User manual

905K Radio Telemetry Module User Manual
 ELPRO Technologies Pty Ltd 2010 Page 16
When the 905K takes a measurement, it will transmit the analog value if the value has changed
by more than the pre-configured sensitivity since the last transmission. The sensitivity can be
configured from 0.1% to 75% with a default value of 3%. If the change in the signal since the
last transmitted value is less than the sensitivity, then the 905K will not transmit the analog
value.
The sensitivity value should be selected which is more than the normal analog signal noise. If
the sensitivity is less than the signal noise, then the 905K will send a lot of un-necessary
transmissions, possibly resulting in jamming the radio channel.
An update transmission of the analog value will be transmitted if the analog value has not been
transmitted for during the user-configurable update period (10 seconds - 7 days). If an update
time of zero is selected, then no update messages will be sent.
If the update time expires since the last transmission, then the last measured value will be
transmitted - that is, a new measurement will not be taken. Normally the update time will be
much longer than the sample time. If the update time is less than the sample time, then update
messages may transmit the same value as the previous transmission, as a new measurement has
not yet been taken.
Overview:
• Measurements of the analog signal are determined by the sample time and warm-up time