ATI
Q46P pH System
Part 6 – Calibration
48
O&M Manual
Rev-F (8/17)
process, and therefore, it is best in most cases to leave it at the default
value. Increasing this value will make the controller more responsive.
Set 4 mA
These functions set the main 4 and 20 mA current loop #1 output points
Set 20 mA
for the analyzer when output 1 is in normal, non-PID, mode of operation.
[Iout1=pH]
The value stored for the 4 mA point may be higher or lower than the
value stored for the 20 mA point. The entry values are limited to values
within the range specified in “Set Range”, and the 4 mA and the 20 mA
point must be separated by at least 1% of this range Use the LEFT arrow
key to select the first digit to be modified. Then use the UP and LEFT
arrow keys to select the desired numerical value. Press ENTER to store
the new value.
*Set 4 mA #2
These functions set the second 4 mA and 20 mA current loop output
*Set 20 mA #2
points for the transmitter. The output may be set to track temperature
[temp/pH]
(default) or pH. The values stored for the 4 mA point may be higher or
lower than the value stored for the 20 mA point.
The entry value is limited to a value between 0 and 55 °C if it is set for
temperature and must be within 0-14 pH if set to track pH. The 4 mA
and the 20 mA point must be at least 20 units away from each other.
Press ENTER to initiate user entry mode, and the value will flash. Use
arrow keys to modify value. Press ENTER to store the new value.
*Set 4 mA #3
OPTIONAL
These functions set the optional third 4 mA and 20 mA
*Set 20 mA #3
current loop output points for the transmitter. The output may be set to
[temp/pH]
track temperature (default) or pH. The values stored for the 4 mA point
may be higher or lower than the value stored for the 20 mA point.
The entry value is limited to a value between 0 and 55 °C if it is set for
temperature and must be within 0-14 pH if set to track pH. The 4 mA
and the 20 mA point must be at least 20 units away from each other.
Press ENTER to initiate user entry mode, and the value will flash. Use
arrow keys to modify value. Press ENTER to store the new value.
*A Setpoint
This function establishes the pH trip point for relay A. The entry value is
limited to a value within the range specified in “Set Range”. Use the
LEFT arrow key to select the first digit to be modified. Then use the UP
and LEFT arrow keys to select the desired numerical value. Press
ENTER to store the new value.
*A Hysteresis
This function establishes the hysteresis, or “deadband”, for Relay A.
Hysteresis is most often used to control relay chattering; however, it may
also be used in control schemes to separate the ON/OFF trip points of
the relay. Press ENTER to initiate user entry mode, and the value will
flash. Use the arrow keys to modify value. Press ENTER to store the
new value.
*A Delay
This function places an additional amount of time delay on the trip point
for relay A. This delay is in addition to the main delay setting for the
controller. The entry value is limited to a value between 0 and 999
seconds. Press ENTER to initiate user entry mode, and the value will