Input For Secondary Current Measurement (X3); Fig. 43: Connecting A Ksr Sensor On The Secondary Side - Bosch Rexroth PST 6 0 Series Operating Instructions Manual

1070080029 / 05 | PST 6xx0
7.2.13

Input for secondary current measurement (X3)

Connection: to X3; STKK, grid 3.5 mm, 8-pole,
max. 1.5 mm
Mating connector is comprised in the delivery.
Cable length: max. 100 m (with recommended cable type)
Cable type: shielded, core area min. 0.75 mm
(e.g.: 2 x 2 x 0.75 mm
Order no.: 1070 913 494)
For the connection of a current sensor, installed in the secondary cir­
cuit.
Some PST units also have an integrated current sensor for the
primary circuit of the welding transformer. This gives you the possi­
bility to choose between secondary and primary measurement (BOS
theme "Programming", "General" tab, "Current measurement" pa­
rameter).
With weld times > 1 s or for temporary suppression in the event of a
sensor failure in the secondary circuit, however, you should change
over to primary measurement - if available.
The timers contain an integrated constant-current regulation (KSR).
Using this function, the timer controls the current flow in the secondary
circuit in such a manner that the programmed command current is ac­
tually reached.
In this way, it is possible to compensate for any process- and handling-
induced fluctuations of the secondary circuit resistance.
This regulation requires a sensor that signals the current flown in the
primary or secondary circuit of the welding transformer to the timer.
X3
1
Toroid input
2
Toroid input
3
Shield
4
5
Shield connection to terminal 3 of X3 !

Fig. 43: Connecting a KSR sensor on the secondary side

The "Measuring loop check" function is available for the automatic
check of the measuring loop.
In order to ensure the proper operation of the sensor, the following
points should be noted:
When installing the sensor, it must be ensured that it is protected
"
against damages resulting from the part to be welded and from ex­
pulsion.
Electric Drives | Bosch Rexroth AG
and Controls
2
.
2
LiYCY,
D
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Assembly
2
,
Secondary circuit