Eurotherm 7000 Series, Руководство пользователя

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7300A User Manual
4-5
Control / Limits
Current limit by threshold. If the
maximum of the three currents
I
M
> I
max
: firing angle variation.
V2 control in ‘Burst mode 16’
Current limit by threshold. If the
maximum of the three currents
I
M
> I
max
: firing angle variation.
P control in ‘Burst mode 16’
Power limit by
control in ‘Burst mode 16’
taking P
max
into account
Current limit by transfer.
If the mean of the 3 currents
squared I
M
2
> V
2
(%):
automatic transfer to I
2
control by
firing angle variation.
Current limit by transfer.
If the mean of the 3 currents
squared I
2
> V
2
(%):
automatic transfer to I
2
control by
firing angle variation.
Power limit by control (variation of
firing angle; new ratio between P
and setpoint.
Setpoint Relinearisation
Current limit using.
If (I
2
)-(I
Min
2
) > 25% I
N
2
:
automatic transfer to I
2
. Mean value
of the 3 currents squared
Firing Control Potentiometer Operation
mode type Name Action of limit
C16 V2CL
VICL
PA V2CL
VICL
I
2
I lim Thyristor unit
current recalibration:
set threshold
I
max
I lim Thyristor unit
current recalibration:
set threshold
I
max
VI lim Power limitation:
set ratio between
P and setpoint
I lim Thyristor unit
current recalibration:
set ratio between
I (%) and setpoint
I lim Thyristor unit
current recalibration:
set ratio between
I (%) and setpoint
VI lim Power limitation:
set ratio between
P and setpoint
I lim Thyristor unit
current recalibration:
set ratio between
I (%) and setpoint
Table 4-2 Operation of current and power limits
4.3. CURRENT AND POWER LIMIT SPECIFICATIONS
The table below summarises the operation of the limits used in the 7300A series power
thyristor units.