Control; Command Value Signal - Bosch Rexroth PSI 6 000 Serie Typspezifische Anleitung

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Device functions
The type of command value input (refer to Sect. 8.2.1 Command value signal),
must match the active regulation mode of the digital welding current
source.
8.2

Control

The digital welding current source is controlled via an external
• command value signal (0 to 10 V
• a weld time signal (24 V
DC
While an active command value signal influences the welding output
generated, the weld time signal specifies when the welding transformer
should be energized.
During this time, command value changes are also accounted for.
8.2.1

Command value signal

Depending on the active regulation mode (PHA, KSR), the following applies:
• for PHA (heat value, or pulse width in this case):
the interface logic of the digital welding current source interprets the
incoming command value signal as the desired pulse width. Depending
on the pulse width input, a current is adjusted in the secondary circuit
which is exclusively subject to the current resistance in the
secondary circuit.
No regulation is active in this mode. A current sensor is not necessary.
Intermediate values are always converted to the corresponding pulse
width by the interface logic using linear interpolation.
Please note that voltage values below 1V are basically interpreted
as 0V, therefore, no activity is initiated.
Refer to Fig.9:
Fixed allocation between the input voltage and the resulting
pulse width.
• with KSR (constant-current regulation):
the command value signal supplied is interpreted as the desired commanded
current.
In this mode, the digital welding current source regulates the actual
current in the secondary circuit automatically. A current sensor is absolutely
necessary.
The way in which the interface logic converts the command value signal
into a commanded current value can be adjusted.
For this purpose, 2 pairs of values must be parameterized which are
each used to define a desired commanded current value if a certain
voltage is present at the command value input.
From these two key values, the interface logic calculates a linear
characteristic by which it converts an active voltage signal to a corresponding
commanded current (in kA).
Please note that voltage values below 1 V are basically interpreted
as 0 V, therefore, no activity is initiated.
1070087044 | PSI 6xxx.000
DC ) and
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