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CD3000E-3PH from 25A to 500A
User’s Manual
27
9.3
Not Critical Alarm
The Not Critical Alarm, doesn’t stop the CD3000E thyristor unit, but is possible to associate an digital
output at these alarms (see par. 12.6).
The parameter P002
allows to visualize the state of these alarms (see par. 14.1).
9.3.1
SCR Short Circuit
This alarm is active when CD3000E read the output current in absence of the input signal. This is
possible if there are a short circuit on the thyristor or if there are a wrong wiring of the load.
When the problem is solved is necessary use the digital input: "Reset Alarm" (see par. 12.5).
9.3.2
Unbalanced Load
This alarm is active when one of the three load current (read on the terminals T1, T2, T3) differs from
the others more than 30%.
The unbalanced alarm could be active also if there are a wrong wiring of the load.
When the problem is solved is necessary use the digital input: "Reset Alarm" (see par. 12.5).
9.3.3
Heater Break alarm (HB)
This alarm is active when the load current decrease under the threshold set on the parameter P066
(see par. 14.3).
The Heater Break alarm could be active also if there are a wrong wiring of the load.
When the problem is solved is necessary use the digital input: "Reset Alarm" (see par. 12.5).
The Heater Break alarm to work properly must have an input signal more then 25% of the nominal
current value.
Caution:
In the first start, and each time that the load is replaced, it’s necessary make the
Calibration procedure.
9.4
Calibration Procedure
The Calibration procedure is an automatic procedure that save in memory the three different values of
load current (for each phase)
This procedure is necessary if you use the Burst Firing (BF) or if you use the Heater Break Alarm.
To make the Calibration procedure follow these steps:
•
Give the power supply and start the thyristor unit (see par. 12.5).
•
Activate the digital input: "Cal" (terminal 19).
•
The CD3000E thyristor unit give the maximum output voltage.
•
After a few seconds the values of voltage and current are stored in memory.
•
The CD3000E thyristor unit returns to the initial situation.
•
Stop the thyristor unit.
The Calibration procedure is done.
Summary of Contents for CD3000 E-3PH
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