Ampcontrol Pty Ltd
– ABN 28 000 915 542
GG2 DISPLAY USER MANUAL
GG2B023 Version 3
– JUNE/19
Uncontrolled Copy - Refer to Ampcontrol Website for Latest Version
Page 58 of 82
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Table 14: Setpoint Configuration
Field Name
Value
SP-ONE
Numerical gas value between
–span value and span value.
Setting must follow the rule that SP1 < SP2 < SP3.
SP-TWO
SP-THREE
HEALTHY
Healthy region setting. The smiley face indicates where the
healthy region lies relative to the setpoints. If the healthy region
is set to always, the hysteresis setting has no effect
HYSTERESIS
0-7.5%, increasing in 0.5% steps. See 6.5.2 for more
information about the hysteresis setting
Hysteresis Setting
The hysteresis setting can help to reduce the number of events which may occur when the gas reading
fluctuates about a setpoint. The hysteresis setting is particularly important in rapid response systems
such as iMAC where exception scans (priority data transmissions) are triggered by high criticality events.
Hysteresis solves this is by padding the setpoint value when clearing the setpoint flag. The example in
Figure 67 shows how the gas reading fluctuates about SP2 (1.25%). The first time the gas reading
reaches SP2, the SP2 flag is set. Then the value decreases and the SP2 flag is cleared. In the diagram
this will happen a further 4 times.
Figure 67: Multiple Triggering Scenario
Hysteresis enables a different value to clear the SP2 flag, i.e. therefore the SP2 value sets the setpoint
flag but a lower value is needed to clear it. The orange line in Figure 68 represents the value needed to
clear the SP2 flag. This is called the hysteresis value.
Figure 68: Using Hysteresis Setting
