Table of Contents
Advertisement
LiAM User's Manual
Considering I
OUT
setpoint and I
as the pre-defined threshold, the regulation fault trips if the following
TH
condition is verified:
This situation could occur if, for example, a 4A current setpoint is fed to a
LiAM power unit that has a 30-Ω resistive load connected to it. Since the output
voltage (i.e. 120V) is beyond rated output voltage, the LiAM unit generates a
regulation fault condition. This fault flag should be reset before turning the output on
again.
Most common operating conditions that may generate the tripping of this fault
are hereafter listed:
-
instability of the output current control loop;
-
a current leakage to earth/ground due to an improper connection of the load;
-
excessive value of the connected resistive load.
3.1.1.1 Load Fault
The "load fault" protection monitors that the resistive value of the load remains
within a defined value interval. This protection is very useful in order to check if all
the loads connected to the power supplies in a large facility installation are correct and
recognizes abnormal load variations.
Considering I
OUT
setpoint and I
as the pre-defined threshold, the regulation fault trips if the following
TH
condition is verified:
where R
EST
function 'MTUNE\r').
The actual real resistive value can be then be expressed by the following
relation:
By substituting this last equation into the previous one, the load fault condition
can be further expressed as follows:
where ∆R = |V
acceptable load variation.
31
as the output current readback value, I
|
as the output current readback value, I
|
is the estimated load resistive value (computed running the
|
|
/ I
| and can be considered as the maximum allowable and
TH
OUT
SET
|
SET
|
|
|
|
|
LiAM Description
as the last stored
as the last stored
Advertisement
Table of Contents
