Fluid Components International FLT93 Nuclear - Manual (Page 38)

OPERATION FLT ® Series FlexSwitch TM
38 Fluid Components International LLC
Low Level Alarm Settings (Sensing Element Normally Wet)
For the low level fail safe setup the following jumpers are to be installed: J18, J20, J23, J24, J27.
The following information is assumed:
Relay is de-energized in the ALARM condition.
Alarm 1 set point is adjusted for the mean value between the air and liquid signals.
Alarm 2 set point is adjusted to approximately half of the liquid signal. (A lower setting might be needed if the liquid is moving.)
High Level Alarm Settings (Sensing Element Normally Dry)
For the high level fail safe setup the following jumpers are to be installed: J18, J20, J23, J25, J26.
The following information is assumed:
Relay is de-energized in the ALARM condition.
Alarm 1 set point is adjusted for the mean value between the air and liquid signals.
Alarm 2 set point is adjusted above maximum signal output for air (not to exceed 7.0 volts).
0.5
1.0
0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
WHEN ALARM 1 DETECTS LOW
LEVEL, THERE IS A POSSIBLE
OPEN ACTIVE RTD OR SHORTED
REFERENCE RTD
WHEN ALARM 2 DETECTS UNEXPECTED
FLOW THAT FORCES THE SIGNAL
BELOW THE ALARM SET POINT, THERE
IS A POSSIBLE HEATER FAILURE,
SHORTED ACTIVE RTD OR OPEN
REFERENCE RTD
SIGNAL
OUTPUT
MEDIA
ALARM 1
SET POINT
DE-ENERGIZED
ENERGIZED
ENERGIZED
C00534-2-2
ALARM 2
SET POINT
AIR
LIQUID
A POWER FAILURE IS DETECTED IF
BOTH RELAYS ARE DE-ENERGIZED
DE-ENERGIZED
Figure 3-7. Low Level Fail Safe Alarm
0.5
1.0
0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
ALARM 2 DETECTS A POSSIBLE OPEN
ACTIVE RTD OR SHORTED REFERENCE
RTD
WHEN ALARM 1 DETECTS HIGH LEVEL,
THERE IS A POSSIBLE HEATER FAILURE,
SHORTED ACTIVE RTD OR OPEN
REFERENCE RTD
SIGNAL
OUTPUT
MEDIA
ALARM 2
SET POINT
ALARM 1
SET POINT
DE-ENERGIZED
DE-ENERGIZED
ENERGIZED
ENERGIZED
C00535-2-2
AIR
LIQUID
A POWER FAILURE IS DETECTED IF
BOTH RELAYS ARE DE-ENERGIZED
Figure 3-8. High Flow Fail Safe Alarm