Fluid Components International FLT93 Nuclear - Manual (Page 23)

FLT ® Series FlexSwitch TM OPERATION
Fluid Components International LLC 23
Detecting Decreasing Flow (low fl ow alarm)
1. Stop the process fl ow and allow the signal to stabilize.
2. Record the no-fl ow signal. (The no-fl ow signal should be greater than the normal fl ow signal.)
No-Flow Signal = ________ volts DC
3. Determine the set point by calculating the average of the normal and no-fl ow output signals. (i.e.; If the normal signal is 2.000 volts and
the no-fl ow signal is 5.000 volts, then the calculated set point would be 3.500 volts.)
4. Record this value.
Calculated Set Point = ________ volts DC
Note: The calculated set point must be at least 0.020 volts greater than the normal signal to ensure that the alarm will reset.
5. Slide the mode switch to the CALIBRATE position.
6. Adjust the calibrate potentiometer (R24) until the voltmeter equals the calculated set point.
7. For the appropriate alarm, determine whether the status LED is on or off (red for No. 1 or green for No. 2).
If the LED is off, turn the set point adjustment potentiometer (R26 for alarm No. 1 or R25 for alarm No.2) slowly clockwise just until the
LED turns on.
OR
If the LED is on, turn the set point adjustment potentiometer (R26 for alarm No. 1 or R25 for alarm No. 2) counterclockwise until the LED
turns off and then slowly clockwise just until the LED turns on.
8. If this is the only fl ow application alarm to be setup, then skip to the Continue With the Air/Gas Flow Procedure.
Detecting Increasing Flow (high fl ow alarm)
1. Establish the excessive process fl ow condition and allow the signal to stabilize.
2. Record the high fl ow signal. (The high fl ow signal should be less than the normal fl ow signal.)
High Flow Signal = ________ volts DC
3. Determine the set point by calculating the average of the normal and high fl ow output signals. (i.e., If the normal signal is 2.000 volts
and the high fl ow signal is 1.000 volts, then the calculated set point would be 1.500 volts.)
Figure 3-3 Flow Application Signal Output
SET POINT
FLOW
OUTPUT VOLT
AG
E
AIR OR GAS
OIL
WATER
LED ON
ABOVE SETPOINT
LED OFF
BELOW SETPOINT
R25 AND R26
Adjust
Clockwise,
Turns
LED ON
Adjust
Counter-
clockwise,
Turns
LED OFF
FIELD ADJUSTABLE
SET POINT
0
Potentiometer
(POT)
C00204-1-2