Carel humiSteam x-plus, User Manual

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54
EN
“UEX-PLUS” +030220621 - rel. 1.4 - 04.08.2009
installer
user
ser
vice
Independent control with temperature probe
See the paragraph on “Independent control with relative humidity probe”.
The unit of measure in this case is °C (°F).
14.3 Operation with two cylinders (only
UE090...UE130)
The humidifi er uses two cylinders to produce steam. The operation of
each cylinder, as well as the management of the corresponding alarms,
is independent. If one cylinder stops steam production (e.g. alarm in
progress), the other continues operation. There are two types of operation
with two cylinders: “parallel sequence” and “series sequence”(installer
menu > regulation type > cylinder sequence).
Parallel sequence (default mode)
In this sequence the two cylinders work so as to produce, in percentage
terms, the same quantity of steam. The steam request is divided into
two equal parts, so that each cylinder produces exactly half the overall
requirement. As the minimum production of each cylinder is 20%, the
minimum production of the humidifi er is 20% of the total rated value.
In parallel sequence the wear on the cylinders during the life of the
humidifi er is very similar (they are used in the same mode and for the
same time).
Series sequence
In this mode the fi rst cylinder works more than the second, in both
percentage and time terms. The total steam request is divided between
the two cylinders in the following way:
if the request is less than 50% in steady operation, only the fi rst cylinder
•
will be operating,
if the request exceeds 50% the second cylinder will also be activated.
•
The minimum production may be as low as 10%.
In series operation the fi rst cylinder becomes depleted more quickly than
the second.
Compensation logic
To ensure the delivery of the required quantity of steam, the controller
manages the operation of the two cylinders so that, if one of the two
cannot deliver the amount required, the other is automatically activated
to make up the diff erence.
This logic is very important, above all in cases where one of the two
cylinders is stopped by an alarm.
14.4 Supply water conductivity
Conductivity measurement and alarms
The conductivity of the supply water is measured by the conductivity
meter when the fi ll solenoid valve is opened.
Two alarm thresholds are available (installer menu > water conductivity
> warning/alarm):
warning threshold (default 1000 uS/cm), signal only without activating
•
the alarm relay (automatic reset when the condition is no longer
present);
alarm threshold (default 1250 uS/cm), unit shutdown with activation
•
of the alarm relay.
The alarm is activated when the reading exceeds one of the two
thresholds continuously for 60 minutes, or alternatively instantly if the
value read is 3 times higher than the threshold.
To disable the alarm signal, simply set the thresholds above the maximum
value of the reading.
Overriding the conductivity of the supply water
In conditions where the supply water has relatively low conductivity, a
higher conductivity value can be set (installer menu > water conductivity
> override conductivity). In this mode, if during the start-up phase the
water touches the high level sensors (with consequent partial draining),
and the steam production has not yet reached the rated value, the
successive water fi ll cycles will last longer than the rated value so as to
reach steady operation faster.
14.5 Automatic draining
The humidifi er automatically drains and replaces some of the water
contained in the cylinder, to prevent an excessive concentration of salts
following the evaporation process.
The drain pump is opened for a set time whenever the conductivity
exceeds the maximum limit; this situation is measured indirectly by
evaluating the evaporation speed).
During the automatic draining phase, the electrodes are off , so as to
prevent the drain water from carrying current.
Powered draining
To enable powered draining: installer menu > drain options > contactor
OFF during drain.
Duration and frequency of the drain to dilute cycles
The duration and the frequency of the drain to dilute cycles can be set
according to the characteristics of the supply water (installer menu >
drain options > dilution drain time and frequency). For example, with
highly conductive water, the duration and frequency of the drain to
dilute cycles should be increased. This will avoid excessive concentrations
of salts inside the cylinder.
Drain due to excess foam
With certain types of supply water, foam may form during the production
of steam just above the water. This situation must be resolved, as it may
cause water to be released together with the steam. For this purpose, two
electrodes are fi tted on the top of the cylinder. When these electrodes
detect the presence of foam, the humidifi er activates a series of repeated
drain cycles. If the situation persists, the complete washing of the cylinder
is activated.
The complete washing of the cylinder can be disabled, so as to guarantee
steam production, even if reduced, in applications where continuity of
service is required (installer menu > drain options > disable complete
emptying for foam).
Drain due to inactivity
In humidifi er does not operate for an extended time (it remains on
but does not produce steam), the water in the cylinder is drained
automatically, to avoid stagnation and hygiene risks.
To disable the periodical drain due to inactivity: installer menu > drain
options > drain after inactivity.
To set the inactivity time: installer menu > drain options > inactivity days
(default 3 days).
Draining due to a signifi cant reduction in the request for
production
In the event of a signifi cant reduction in the request for steam production,
the humidifi er, rather than wait for the level of water (and thus the
production) to decrease due to the eff ect of the production itself,
performs a drain cycle. The reduction in the request for steam production
is considered signifi cant if the current is 33% higher than that relating to
the requested level. This function can be disabled: installer menu > drain
options > drain if steam request drops.
Periodical drain
When using water rich in substances such as humus, lime and impurities,
the effi
ciency and the operation of the humidifi er may be aff ected. In
these cases, a periodical drain cycle should be set for the cylinder top
avoid accumulating residues.
To enable the periodical drain: installer menu > drain options > periodic
cylinder fl ush
To set the drain interval: installer menu > drain options > time interval