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 6 of 8
Control Philosophy
Control Concept – Multiple System
b. Control Concept – Multiple System
This part is describing the basic principles of the Omega Filter’s control system. This information is
applicable for both; control panels provided by Amiad or panels provided by others.
Multiple filtration system is an installation of a few filter units on a common manifold system.
The flow is divided between the units by the natural hydraulic resistance of the filter units and the piping
system.
The system should be hydraulically designed to provide optimal balance and equal flow through the
filtration units.
Since the TSS load distribution is never identical to the flow distribution, even if the design is perfect,
some filter units will be clogged before others. However, the DP across these filters will remain equal in
all units, only the flow distribution will be changed. Therefore, the DP measuring should always be done
between the main inlet manifold and the main outlet manifold.
Flushing of the system is done in sequence - one unit after the other. Every flush cycle must include all
the available filters in the system.
In large multiple systems, simultaneous flushing of two or more units at a time can give significant
advantage, especially in peak loads situations.
The following description focuses on the system level of the control while the control details of the
individual filter can be found in the Standalone Omega filter description.
Electrical Components On Each Filter Unit
•
0.55, 0.75, or 1.2KW, 3 Phase motor (Two rotation directions)
•
2 X NC Proximity Switches or mechanical limit switches
•
3 way NC Solenoid (Operating Pneumatic Actuated Butterfly exhaust Valve).
Common Instrumentations for The Entire System
•
One of the below instrumentations options:
a. PDT 4-20 mA pressure differential transmitter
b. 2 x PT 4-20 mA pressure transmitters (inlet / outlet)
c. PDS
pressure differential switch
Functional Description
1. Request for Flushing:
Flush Cycle will start as a result of any one of the following triggers.
•
Pressure Differential:
Same as for a single filter unit, just measuring done across the entire filtration battery.
•
Remote Start:
Free Potential Signal from Supervision system start flush cycle of the entire system.
•
Local Start:
“Group Test” Pushbutton on local control panel – start cycle of the entire system.
“Test Filter # 1” Pushbutton on local control panel – start cycle for each filter unit (for maintenance and testing).
•
Time Interval:
Flush Cycle starts if the accumulated time from last flush cycle reaches the Interval Set-Point.
The Time counter re-sets back to zero when the flush cycle starts, regardless if it is caused by DP or by time.
•
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.