Endress+Hauser RIA 450 Manual De Instrucciones página 55

Alternating relay control ALT:
Equal use of more than one pump in level control applications
is done by alterately switching individual pumps.
It is no longer conditional to reach a preset switch point before
switching the pump, it is more a case of which pump was
inoperative for the longest time.
The same condition is valid for switching the pump off, except
here the pump with the longest operation time is switched off.
Switch
condition
Switch
condition
Set points not used in the alternating relay control will operate
as normal (see the relevant part of these instructions).
- This function can be allocated to individual relays.
Not allocated relays are not monitored for on or off
- When using the alternating relay control function, the set points
are no longer fixed to individual relays. This is because the
relay switch point is dependent on the on or off running time of
individual relays.
- Changing a set point parameter resets all counters to zero.
Mode MAX
With alternating pump control
Without alternating pump control
À
Relay de-energised
Process display
53