Operating instructions

Calibration
Page 19
Automatic Calibration Routine
Calibration can be run at any time during normal operation except the self-test period (from 10 minutes before the
self-test until the self-test is complete). Calibration is a one man operation and virtually automatic.
Note: For Calibration gas concentrations and flowrates for each gas, see Appendix A (page 25)
To Calibrate perform the following steps: LCD Icons Displayed Display
START CALIBRATION
1. Press and hold the external button down while
the LCD displays the Alarm Setpoints.
Continue to hold down until the display reads
“CAL“ (approx. 5 seconds) and then release the
button.
The 4-20 mA output will be 3 mA throughout
calibration. Calibrating the GasPoint will not
cause false alarms at the controller.
First, the LOW and HIGH alarm
setpoints will be displayed (8
seconds approx)
Next, the CAL icon lights for 3
seconds
Gas type is constantly displayed
Backlight is activated
AUTO ZERO
The GasPoint will then take a zero level reading
The display is as shown.
2. Combustible and Toxic Sensors: If background
gas is present, apply zero gas (pure air or 100%
nitrogen) to zero the sensor. Restart the
Calibration sequence.
3. Oxygen Sensor: Gas is not required. Auto Zero
sequence will take 30 to 60 seconds.
Numeric display will read “00”
"Auto Zero" advice flashes
Gas monitored is constantly
displayed
AUTO SPAN
3. Insert cal cap (1) and apply gas to the sensor
for approx. 2 minutes (Ammonia 5 minutes).
See Appendix A for concentrations and
flowrates.
4. When the countdown "300" to "00" begins Span
is complete, disconnect the gas.
If Span Fails: Check calibration gas cylinder
used and concentration expected. Replace the
cylinder and/or change the cal gas expected
value, if required. Recalibrate.
Oxygen Sensor: Use Pure Air Calibration Gas
(20.9% O
2
) in case o of deficient ot enriched
Numeric display will show
calibration gas value expected
Gas cylinder icon flashes
"Span" advice lights
Gas type is constantly displayed
After a successful calibration
GasPoint automatically returns to
normal operation and displays the
current reading ppm or % present.
Exiting Calibration Routine (Fail or Error):
Auto Zero Fail: If the "Fail" icon lights, the LCD
will display a countdown from "300" to "00",
before GasPoint begins normal operation.
AutoSpan Error: If the "Error" icon lights, the
LCD will display a countdown from "300" to "00",
before GasPoint begins normal operation.
Note: In either fail condition occurs, all previous
information values are retained. Retry.
Auto Zero: If the target or an
interfering gas is present GasPoint
will refuse to auto zero. The “Fail”
icon lights. The “Fail” icon will also
light if the external pushbutton is
pressed during auto zero.
Span: If the cal gas is not within
expected values, the GasPoint will
refuse to span. The "Error" icon
will light.