DAB MCE-55/P, Instruction For Installation And Maintenance

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6.5.9 FI: Flow sensor setting
This enables setting of operation as described in Table 17.
Flow sensor setting
Value Type of use Notes
0 without flow sensor
1 single specific flow sensor (F3.00) default
2 multiple specific flow sensor (F3.00)
3 manual setting for a general single pulse flow sensor
4 manual setting for a general multiple pulse flow sensor
Table 17: Flow sensor settings
In the case of multi inverter operation, use of multiple sensors can be specified.
6.5.9.1 Operation without flow sensor
When the setting without flow sensor is selected, the FK and FD settings are automatically disabled as these
parameters are not necessary. The parameter disabled message is indicated by an icon showing a padlock.
It is possible to choose between 2 different operating modes without flow sensor by means of the parameter
FZ (see par. 6.5.12):
Minimum frequency mode: this mode allows you to set the frequency (FZ) below which it is considered that
there is zero flow. In this mode the electropump stops when its rotating frequency falls below FZ for a time of
T2 (see par. 6.6.3).
IMPORTANT: An incorrect setting of FZ causes:
1. If FZ is too high, the electropump could cut out even in the presence of flow and then start again as
soon as the pressure falls below the restarting pressure (see 6.5.5). So there could be repeated
episodes of switching on and off, even quite close together.
2. If FZ is too low, the electropump might never stop even in the absence of flow, or with very low flows.
This situation could lead to damage of the electropump due to overheating.
NOTE: Since the zero flow frequency FZ may vary as the Setpoint varies, it is important that:
1. Whenever the Setpoint is changed you check that the set value of FZ is adequate for the new
Setpoint.
2. Whenever auxiliary Setpoints are used, you check that the set value of FZ is adequate for each one
of them.
Self-adaptive mode: this mode consists of a particular and efficient self-adaptive algorithm which allows
operation in nearly all cases without any problem. The algorithm acquires information and updates the
relative parameters during operation.
To ensure optimal operation, there should not be any substantial
periodic variations on the hydraulic system, which cause significant differences between values (such as
solenoid valves that exchange hydraulic sectors with very different characteristics), as the algorithm adapts
only to one of these and cannot provide the expected results as soon as switching is performed. On the
other hand, if the system remains with similar characteristics (elasticity length and minimum required flow
rate) there are no problems.
On each restart or reset of the unit, the self-learnt values are reset, and therefore a specific time interval is
required to self-adapt.