Owner manual

FLUID COMPONENTS INTL CHAPTER 3 - OPERATION
FLTÔ Series FlexSwitchÔ 3 - 20 Doc. No. 06EN003246 Rev. B
Fail Safe Alarm Setting
These procedures set the second relay to detect component failure (fail-safe).
Low Flow Alarm Settings
For the low flow fail safe setup the following jumpers are to be installed: J18, J20, J23, J24, J27.
Figure 3-5. Low Flow Fail Safe Alarm
High Flow Alarm Settings
For the high flow fail safe setup the following jumpers are to be installed: J18, J20, J23, J25, J26.
Figure 3-6. High Flow Fail Safe Alarm
The following information is assumed:
Relay is de-energized in the ALARM condition.
Alarm 1 set point is adjusted for desired high flow alarm velocity or signal.
Alarm 2 set point is adjusted above maximum signal output (under range flow not to exceed 7.0 volts).
The following information is assumed:
Relay is de-energized in the ALARM condition.
Alarm 1 set point is adjusted for desired low flow alarm velocity or signal.
Alarm 2 set point is adjusted slightly below minimum signal output (over range flow).
0.5
02010 30 5040 60
1.0
0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
WHEN ALARM 1 DETECTS LOW
FLOW THERE IS A POSSIBLE OPEN
ACTIVE RTD OR SHORTED
REFERENCE RTD
WHEN ALARM 2 DETECTS OVER
RANGE FLOW, THERE IS A POSSIBLE
HEATER FAILURE,
SHORTED ACTIVE RTD OR
OPEN REFERENCE RTD
SIGNAL
OUTPUT
AIR FLOW RATE
ALARM 1 SET POINT
ALARM 2 SET POINT
DE-ENERGIZED
DE-ENERGIZED
ENERGIZED
ENERGIZED
C00534-1
A POWER FAILURE IS DETECTED IF
BOTH RELAYS ARE DE-ENERGIZED
0.5
02010 30 5040 60
1.0
0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
WHEN ALARM 2 DETECTS AN
UNDER RANGE FLOW, THERE IS A
POSSIBLE OPEN ACTIVE RTD OR
SHORTED REFERENCE RTD
WHEN ALARM 1 DETECTS HIGH
FLOW, THERE IS A POSSIBLE
HEATER FAILURE,
SHORTED ACTIVE RTD OR
OPEN REFERENCE RTD
SIGNAL
OUTPUT
AIR FLOW RATE
ALARM 2 SET POINT
ALARM 1 SET POINT
DE-ENERGIZED
DE-ENERGIZED
ENERGIZED
ENERGIZED
C00535-1
A POWER FAILURE IS DETECTED IF
BOTH RELAYS ARE DE-ENERGIZED