ATI
Q46H/65 Residual Chlorine Dioxide System
Part 6
– Configuration
48
O&M Manual
Rev-J (11/18)
Failsafe
This function allows the user to set the optional system relays to a
failsafe condition. In a failsafe condition, the relay logic is reversed so
that the relay is electrically energized in a normal operating state. By
doing this, the relay will not only change state when, for example, a ClO
2
limit is exceeded, but also when power is lost to the controller.
When failsafe is selected to be ON, the normally-open contacts of the
relay will be closed during normal operation. In an attempt to make this
configuration less confusing, the LCD icon logic is reversed with this
setting, and the icon is OFF under this normal condition. Therefore,
when the trip condition occurs, the closed N.O. contacts will be opened
(relay de-energized), and the LCD icon will illuminate. In addition, a
power fail would also cause the contacts to open.
Start Delay
This function is designed to minimize control or alarm issues arising from
temporary power loss. When power goes down, the monitor records the
analog output values and the status of relays and PID functions. When
power is restored, the analog values and relays will be held at the pre-
power loss values for a defined
period of time. This “start delay” may be
programmed for periods from 0-9.9 minutes. This function is set to 0.0
minutes by default and must be activated by the user if desired by setting
a positive time value
Set Default
The Set Default function allows the user to return the instrument back to
factory default data for all user settings or for just the calibration default.
It is intended to be used as a last resort troubleshooting procedure. All
user settings or the calibration settings are returned to the original factory
values. Hidden factory calibration data remains unchanged. Press
ENTER to initiate user entry mode and select either All or Cal with the
UP arrow key.
