18
AirAware
ModBus Interface
The AirAware is a ModBus RTU compliant instrument. Please consult the
factory for detailed information of ModBus registers and settings for board
jumpers P1, P2 and P3.
Bump (function) Testing
Bump (function) testing is the act of
applying a known concentration of gas to
the monitor and verifying that the
instrument is performing properly. There
are two common philosophies when it
comes to BUMP or FUNCTION testing.
Applying gas to the instrument while in
the normal run mode and awaiting a
response within the allotted time is easily
achieved. When applying gas through the
calibration adapter, the unit should
respond to 90% of the reading within 2-3
minutes (sensor specific).
007
At this point all on-board and remote alarms should be activated and the 4-20
mA signal should reflect the display reading on the instruments.
If a test of the sensor and display only is required without the activation of on-
board or external alarming devices, selecting the “BUMP” option in the Set-up
mode disables all alarming functions. At this point, the alarm relays* are
disabled, audio alarms* are disabled and the current output* locks at 3.0 mA
for all gases except oxygen, which goes to 16.0 mA. Instrument automatically
returns to normal operation.
If an instrument fails to operate properly following any bump “functional”
test, a full instrument calibration should be performed prior to use. Refer to
Section 11 (Calibration) for details.
Test gas kits for all gases, including oxygen, are available from Industrial
Scientific Oldham; see page 25 for ordering information.
