amiad Omega 13.5K, Руководство по установке и эксплуатации

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OMEGA F ilt ers – Ins tal lati on & Oper atio n Manu al Pag e 7 of 8
Control Philosophy
Control Concept – Multiple System
2. Number of filters flushing simultaneously:
Flushing of two or more filters simultaneously is shortening the duration of the flushing cycle and
recovers the DP across the system faster. It is essential in big systems and in heavy load conditions.
It is recommended to have it as an option in every multiple system. However, the drain piping system
mast be designed to handle the extra flow.
It is possible to add features to the PLC logic so that if a new DP signal is received before the end of the
current flush cycle, the PLC automatically adds one unit to flush simultaneously.
3. Faults & Alarms:
In this document Fault is defined as a situation in which the Filter/ Filtration System is out of order, cannot
clean itself and must be shut down.
Alarm is defined as situation in which some elements in the filter or some filters in the system are in fault
mode but the system is still functioning and filtration may continue.
The same logic that applies in a standalone unit is relevant with multiple systems.
Filter unit that is in a mechanical fault mode and cannot flush, is skipped in the sequence and will be
considered as an Alarm in the multiple system level.
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Potential System faults:
1. DP Value > Set-point for more than 20 minutes (pre-determined depends on system size).
2. No filter ava request for flushing.
3. Pressure transmitters are faulty or out of range.
Filter unit can be "Not Available" because it was taken offline or due to mechanical fault (as
described in details in the "Standalone Filter Description").
4. Flush Cycle Stages:
Filters are flushing as described in the single filter section.
The flush valve of the next filter open as soon as the flush valve of the previous filter turns off.
A complete Flushing Cycle is considered if all the available units finished the flush cycle.
5. Reset:
Pressing on the Reset Push-button causes:
a) Stop the current filter flush cycle and the sequence to the next filter.
b) Clear Fault mode in both, filter and system levels.
6. Pause:
Signal in the PAUSE input will stop the flush cycle (same as Reset). As long as this input is ON, the
system will not enter a flush cycle.
7. Continuous Flushing mode:
Continuous Flushing in system level means that the system is flushing in sequence and at least one filter
unit is in flushing mode at all times, regardless of the DP across the system. The number of filters
flushing simultaneously depends on the size of the system and the hydraulic conditions.
It is recommended to use the continuous mode for limited duration in order to prevent high wear of the
filter internals.
a. Manual operation of Continuous mode:
Same as for single unit.
b. Automatic operation of Continuous mode:
Same as for single unit.