BRONKHORST mini CORI-FLOW ML120, Instruction Manual

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Bronkhorst®
Instruction Manual mini CORI-FLOW ML120 9.17.097G 58
In FlowPlot, the valve power parameters are set on the
Controller tab of the Instrument Settings :
·
Valve maximum sets the power needed to fully open the
valve
·
Valve open sets the power needed to keep the valve open
(hold signal)
Optimum values might differ, depending on the specifics of
the valve.
If the use of the valve power parameters seems somewhat counterintuitive, note that usage here is specific to shut-off
valves. For control valves, the purpose of the Open and Max parameters is more straightforward.
The valve power settings can be done with the following digital parameters:
Name Process/
Parameter
Modbus
register no
Value Purpose/Remarks
Valve Maximum (231) 114/25 62153…
62154
as required set minimum power for opening shut-off valve
Valve Open (190) 114/24 62145…
62146
as required set minimum power to keep the valve open
5.4 Optimizing hints
Problem Possible cause Action
Batch size overshoot not reduced
after more than 3 batches
Dosing time too short
·
Decrease inlet pressure
·
Decrease maximum capacity *
Counter control gain too high Decrease counter control gain *
Dosing time too long Flow rate too low
·
Increase inlet pressure
·
Increase maximum capacity *
Counter control gain too low Increase counter control gain *
Controller too slow Optimize PID controller *
Pump speed adjustment too slow Increase controller speed (when using a pump,
controller speed values up to 10 can be used)
New batch cannot be started New batch trigger(s) not defined Enable new batch trigger(s) (see Batch settings )
Flow continues after configured
batch size is reached
New setpoint on limit > 0% Set New setpoint on limit to 0% (see Batch
settings )
Counter value still changes after
limit is reached
Measuring signal disturbed by
electrical noise
Increase minimum capacity (see Disabling
filters )
Zero point drifted Adjust zero point (see Zeroing )
Gas inclusion in tubing Flush instrument and tubing at relatively high
flow rate before starting batch control