Current Limit; Current Limit Setting; Current Limit Tuning Procedure - CD Automation Revo C 3PH User Manual

14 Current Limit

The Current Limit is available on REVO CL with Phase Angle firing mode only.
It control the firing angle of the thyristor to maintain the three RMS current under the set value.
When the current exceeds this value, the voltage is decreased up to reach the current limit set.
I Load <= I Limit Set

14.1.1 Current Limit Setting

The setting of the current limit value can be done in two ways :Digital or Analogic.
 Digital: Set the parameter from the hardware menù
Set the current limit value by the parameter . from 0 a 100% Of the Current. (Operator menu)
 Analogic: Set the parameter from the hardware menù
The value of the Current Limit is setted with analog input 2 Teeminals 11 (-) e 4 (+).
This analog input is 0 – 10V and input impedance 10Kohm.
The settings functions by the analogic input 2 is called also External current limit profile because
allows to change the profile of the Current Limit during the process .
Caution: this procedure must be performed only by qualified persons.

14.1.2 Current Limit tuning procedure

 Give the power supply and set the current limit to zero:
- In analog mode, set the analog input 2 to zero
- In digital mode, set the parameter=0
 Start the thyristor unit .
 Set the primary input or the setpoint value at 100% .
 Increase the current limit
- In analog mode increase the value of the analaog input
- In digital mode increase the parameter
until to reach the desired value of rms current .
 Stop the thyristor unit.
The Current Limit Procedure is done.
Neut-Eng-REVO-C-3PH-300-800A-Thyristors-Units
REVO C
I Load > I Limit Set
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