Etatron eOne MF Series, Operatinginstructions And Maintenance

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ENGLISH
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REFERENCE IMPULSES Number of impulses that the circuit samples
MAX DIFFERENCE Maximum number of pulses permissible within the sampling interval,
that cannot be effectively provided
To better explain this function, consider for example, a sampling interval set to 100 impulses and a maximum allowable
difference of 10 pulses. The circuit memorises the impulses of the electromagnet and in correspondence to each of these it
expects a corresponding closing of the contact of the flow switch connected to the hydraulic delivery of the pump. If the
closures recorded are greater than or equal to 90 (100-10 = 90), the pump is operating normally and repeats the next
sampling cycle. If, however, the closures recorded are less than 90 the pump goes into alarm mode signalling the situation in
the manner indicated above.
Within the programming menu you can choose whether or NOT to STOP the metering in the case of an alarm.
Meter impulses alarm
The impulse meter alarm activates in the multiplicative operation modes, namely: 1 x N (m), PPM e ml x m
3
.
This alarm is activated when the number of pulses generated by the meter is such as to require the pump to run at a
higher frequency than the maximum. This event may be generated by an incorrect programming or an incorrect choice of the
meter or by the metering pump in relation to the plant to be treated. The user in the programming menu can choose whether
to enable this type of alarm. It is recommended however to enable it to provide a greater guarantee of correct metering and
sizing check. It is also possible to choose, always within the programming menu, whether or NOT to STOP the metering in
the case of an alarm.
The alarm activates when the number of injections memorised and not dispensed exceeds the value 4 * N where N is
the number of injections to be given for each meter impulse. On the pump display the number of injections to be yet delivered
is shown in dynamic mode. The choice of factor 4 is an easy way to prevent any transient phenomena generating false
alarms.
If the activation of this alarm is frequent it is recommended that the operator checks the operating conditions
of the plant.
The innovative HRS technology has enabled the development of a range of metering pumps that have the
ability to detect any changes in pressure inside the plant or malfunctions related to these variations. The pump is
able to provide useful information about the state of operation. Specifically, this is expressed in the availability of
two different types of signals.
a) UNDERLOAD: If during normal operation the pump has no fluid to be metered which may be caused by
problems on the suction line: clogged filter or damaged valves, the pump goes into UNDERLOAD status. This
condition is indicated by the signal on the display, the ALARM LED lights up and activates the corresponding
relay (if enabled). The pump stops after approximately 20 injections.
b) OVERLOAD: The pump during normal operation performs a check (in real time) on the pressure
conditions in the plant. If this pressure exceeds the maximum allowed (plate setting), the instrumentation of the
pump reacts reporting this state with a message on the display, the ALARM LED lights up and the relay activates.
Even in this case, the stopping of the pump occurs after 20 injections from the occurrence of the event. Under
particular conditions of pressure could occur the OVER-LOAD alarm even with air presence in the pump body. We
recommend that you take action to check the pump.
The UNDER-LOAD and OVER-LOAD functions can be enabled and disabled using the respective setup
menu. The factory settings for the UNDER LOAD and OVER LOAD functions are disabled.
Relay services output
In each submenu, you may enable or disable the intervention of a release associated to one or more of the
following alarms:
• Level alarm
•
Flow switch alarm
•
Meter impulse alarm that intervenes in the 1xN (M) function
•
Meter impulse alarm in PPM
• Meter impulse alarm in ml x m3
•
UNDERLOAD alarm
•
OVERLOAD alarm
By default, the alarms mentioned above are all disabled , except for the LEVEL ALARM (default ENABLED)