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3D TRASAR
5500 - Installation & Operation Manual
18. What is 3D TRASAR Bio-Shock Mode? (con’t)
During the slug feed period bio-reporter feed is suspended and oxidizing biocide is applied based
on timer control or system ORP measurement. For timer based slugs the oxidant relay is on con-
tinuously for the preset time. For ORP based slugs, the oxidant is dosed to the specified ORP level
and then maintained at that ORP level for the preset time. Bio-Reporter feed restarts after the
system water has returned to pre-slug ORP values.
Since the oxidant slug condition is defined by the user, the actual oxidant applied
can be
adjusted.
If an increased oxidant dosage is desired, the ORP set point and/or the slug duration can be in-
creased. Please note that there is NO oxidant feed between slugs. Under classic 3D TRASAR Bio-
Control, the oxidant dosage cannot be adjusted.
3D TRASAR Bio-Shock Mode requires a functional ORP probe to be in place and recalibrated.
The ORP probe is used to control the oxidant slug and monitor the system in the recovery period
following the slug. Once the ORP signal has dropped to within 5% of the pre-slug levels, the
bio-reporter is redosed. If the ORP signal does not fall back to within 5% of the pre slug level within
24 hours (default value), the system will trigger a “slug recovery failure” alarm, and the oxidant will
be dosed based on the failsafe settings. When the alarm is cleared (either by acknowledging the
alarm on the 3D TRASAR controller screen or through a power cycle), the system will return to
normal operation and resume bio-reporter feed.
The figure below shows the bio-reporter ratio value during 3D TRASAR Bio-Shock mode. When it
reaches the setpoint the Oxidant relay is triggered (to 129). The Oxidant relay remains under ORP
control for the preset duration. Thereafter when the ORP signals returns to preslug values and the
recovery period is complete, bio-reporter is again dosed into the system and the ratio is monitored.