Redundancy Mode - Siemens SITRANS FC430 Operating Instructions Manual

Functions
8.6 Inputs and outputs
● Direction = Positive
● Frequency Value High = 12 kHz
● Frequency Value Low = 2 kHz
● Flow Value High = 15 kg/s
● Flow Value Low = 5 kg/s
Measured massflow value = 7.5 kg/s (constant)
Result:
● Frequency = 4.5 kHz
Note
The connected equipment must be capable of registering the full range of frequencies
configured.
8.6.4

Redundancy mode

If both channel 2 and channel 3 are configured as either pulse outputs or frequency outputs,
channel 3 can be configured for redundancy mode to follow channel 2 shifted by 90˚or 180˚
of the functional width of the pulse. If set to redundancy mode, channel 3 inherits all channel
2 settings. The functional width of the pulse is two times the pulse "On" duration. The flow
direction will determine whether channel 3 is shifted before or after channel 2.
The following examples describe the pulse functionalities for channel 2 and 3 in redundancy
mode:
Channel 2 configured as positive direction and channel 3 set to redundancy mode 90°
Figure 8-8
Figure 8-9
146
Positive flow - channel 3 leads by 90°
Negative flow - channel 3 lags by 90°
Operating Instructions, 05/2015, A5E03361511-AF
FC430 with HART