Independent Relay Failsafe (P129) - Siemens sitrans LU01 Instruction Manual

For IN-BOUNDS and OUT-OF-BOUNDS Relay Functions (P111 = 2 and 3 respectively), a
dead band prevents relay chatter due to material level fluctuations at both the upper and
lower setpoints.
Enter the dead band in either percent of
span or units of measure (P005). The
deadband value is applied both above
and below the upper and lower bound
setpoints as shown in the figure.

Independent Relay Failsafe (P129)

P129 Relay Failsafe
Sets the failsafe operation per relay to allow for more flexible programming.
Primary Index
Values
Altered by
Related
Use this for operations independent of the Failsafe Material Level (P070).
Relay Failsafe is only available for the following relay functions (P111) and is not used for
any other relay control function.
Relay Function (P111)
1 – level alarm
2 – in bounds alarm
3 – out of bounds alarm
4 – rate of change alarm
5 – temperature alarm
50 – all pump controls
To select an independent Relay Failsafe value:
1. Press FUNCTION
2. Press ARROWS
3. Select option and press ENTER
Page 46
Relay
OFF * Response governed by P071 Failsafe Material Level
HOLd For LAST KNOWN relay state retention
dE To have the relay de-energize immediately on failsafe
En To have the relay energize immediately on failsafe
• P071 Failsafe Material Level
• P070 Failsafe Timer
• P111 Relay Control Function
OFF
dE
to display the Auxiliary Function symbol.
to scroll through the failsafe options.
.
SITRANS LU01 – INSTRUCTION MANUAL
Actual ON or OFF setpoint
P116, deadband
Setpoint set in P112 or P113
P116, deadband
Actual OFF or ON setpoint
Preset (P129)
7ML19985BE02