Configuration; Isolate Mode - GasTech GTA-4100R Operator's Manual

Configuration

3
This section will outline and explain in detail the various stages of configuring a system. This section should be
referenced when commissioning a new system but also as when changing transmitter or sensor types.

• Isolate Mode

• Configuration & Programming
• Configuration Examples
• Calibration
3.1 Isolate Mode
The Isolate feature is designed so the operator can do maintenance/calibration on that channel without
causing unwanted alarms.
To turn that channel into Isolate modem flick the "Isolate" switch from right to left. The display will change to
an inverted mode as seen in the picture below. The isolate switch will isolate all alarms from that channel only
- not the complete card. The 4-20mA output will change to 2mA indicating the channel is in Isolate mode.
NOTE: The Isolate mode can be selected if a channel is giving spurious alarms and investigation is in the
process this will eliminate any alarms during the investigation period.
If a sensor takes longer than 30 seconds to stabilize or come on line the Isolate mode can be selected until the
sensor comes on line. The display will still show the sensor readings during this time.
NOTE: The GTA-4100R advanced software has a feature called zero suppression, which monitors the
sensor performance and small sensor drifts, which is a characteristic of all sensors. This drift is due to
sudden temperature, humidity and pressure changes or aging sensors. Normally the advanced electronics
and software will remove this insignificant drift and keep the detector reading zero or 20.9 (for an Oxygen
sensor). However in isolate mode the zero suppression feature is turned off, so during calibration the
channel can be exactly zeroed without the dead band masking.
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