Temperature Protection; Operating Times; Alarm Reset - ITALFARAD SPC Instrucciones De Uso

3.2 Current protection
The input line current, measured in true RMS, is compared with the reference value
preset at 150% of the rated value (preset primary current). If the threshold value is
exceeded for a time longer than 3 seconds, visual signalling is enabled (flashing of the
current and alarm led's) and the alarm relays are operated.
3.3 THD protection
The current signal is processed in order to extract its total harmonic distortion. Such
value is compared with the preset threshold value. If the threshold value is exceeded for
a time longer than the preset time, visual signalling is enabled (flashing of the THD and
alarm led's) and the alarm relays are operated.

3.4 Temperature protection

The measured temperature is compared with the preset temperature threshold. If the
threshold value is exceeded for a time longer than the 10 seconds, the FAN led lights up
and the cooling device control relay is operated, If the temperature exceeds the sum of
the threshold value and delta temperature value, visual signalling is enabled (flashing of
the T° and alarm led's) and the alarm relays are operated. Such alarm can only be reset
manually.
The contact of the cooling device control relay is opened under temperature alarm
condition.
The instrument is supplied with external temperature probe.

3.5 Operating times

The operating times for all protections given by the instrument are of the integrating
type; i.e. they take into account the previous times for exceeding the alarm thresholds
as shown in the figure:
Resetting of the integrating alarm timers can either be manual by pressing the RESET
button (for about 5 seconds) or else automatic after the elapsing of a time equal to the
operating time without the dimension exceeding the limiting threshold.

3.6 Alarm reset

When an alarm event occurs, the instrument signals the condition by flashing both the
alarm led and the led associated with the dimension under alarm and it energizes the
two alarm relays by opening their contacts.
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