A5E33329501 SITRANS LUT400 (HART) – OPERATING INSTRUCTIONS Page 67
mmmmm
General Operation
When totalizing OCM flow:
The flow totalizers continue to operate during a fail-safe condition, thus the external
totalizer relay will also continue to operate.
External Sampler relay
The External Sampler relay operates the same as the External Totalizer relay described above.
The periodic timeout-click will also continue to occur in fail-safe.
Communications relays
Relays controlled by communications (HART) are not affected by a fail-safe condition.
Relay states
The relays on the SITRANS LUT400 are programmable, allowing for many control
schemes.
Relay output logic
Affects relay reaction. Reverses the logic (normally-open to normally-closed or vice
versa). Relay logic can be modified separately for alarms, and controls. (Logic for pumps
cannot be reversed.)
Relay related parameters
Some parameters affect how relays react during normal conditions:
Setpoints
When a setpoint is reached, the corresponding action is taken. The setpoint can be an
ON or OFF setpoint related to a process variable, or a timed setpoint based on interval
and duration.
Relay Types
Relay 1 – NO / NC (Form C)
Relay 2,3 – NO (Form A)
Function Parameter
2.8.11. Relay Logic
for
2.8. Alarms
2.8.11.1. Relay 1 Logic
2.8.11.2. Relay 2 Logic
2.8.11.3. Relay 3 Logic
2.11. Other Control
2.11.1. Elapsed Time Relay 2.11.1.5. Relay Logic
2.11.2. Time of Day Relay 2.11.2.5. Relay Logic
2.11.3. External Totalizer 2.11.3.5. Relay Logic
2.11.4. External Sampler 2.11.4.6. Relay Logic
To Next Page
Loading...
