Emerson Rosemount 3490 Series, Reference Manual

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Table 4-7: Relay Parameters
Parameter Description
Relay 1 (RL1) When relay RL1 mode (P410) is Set Point: Relay RL1 is energized at P411 (on
point) and de-energized at P412 (off point).
Relay 2 (RL2) When relay RL2 mode (P420) is Set Point: Relay RL2 is energized at P421 (on
point) and de-energized at P422 (off point).
Relay 3 (RL3) If relay RL3 mode (P430) is Set Point: Relay RL3 is energized at P431 (on point)
and de-energized at P432 (off point).
Relay 4 (RL4) If relay RL4 mode (P440) is Set Point: Relay RL4 is energized at P441 (on point)
and de-energized at P442 (off point).
In a basic emptying application, the On Point (e.g. P411) is programmed to be greater
than the Off Point (e.g. P412). The Set Point relay energizes when the control unit PV
(D800) exceeds the On Point and de-energizes when the PV value drops below the Off
Point.
In a basic filling application, the On Point (e.g. P411) is programmed to be less than the Off
point (e.g. P412). The Set Point relay energizes when the control unit PV (D800) falls
below the On point and de-energizes when the PV value rises above the Off Point.
There are set point relays modes for the control unit SV value (D801), TV value (D802) and
FV value (D803).
Related information
Optional change: transmitter input channel settings (advanced users)
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