Relay States; Relay Related Parameters - Siemens SITRANS LUT400 Operating Instructions Manual

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.)
Function
2.8. 1 1. Relay Logic
2. 1 1. Other Control

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.
A5E33329501
Relay Types
Relay 1 – NO / NC (Form C)
Relay 2,3 – NO (Form A)
2.8. Alarms
for
2. 1 1. 1 . Elapsed Time Relay
2. 1 1.2. Time of Day Relay
2. 1 1.3. External Totalizer
2. 1 1.4. External Sampler
SITRANS LUT400 (HART) – OPERATING INSTRUCTIONS
Parameter
2.8. 1 1. 1 . Relay 1 Logic
2.8.11.2. Relay 2 Logic
2.8.11.3. Relay 3 Logic
2. 1 1. 1 .5. Relay Logic
2. 1 1.2.5. Relay Logic
2. 1 1.3.5. Relay Logic
2. 1 1.4.6. Relay Logic
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