Ramp Time Selection Logic [19] (Only For Vt-Vspa2; Characteristic Curve Generator [10] - Bosch Rexroth VT-VSPA2-1-2X Series Manual

4-quadrant operation
Ramp time call-ups
Ramp time "t5"
Adjustment options
5.2.6 Ramp time selection logic [19] (only for VT-VSPA2.../T5)
The ramp time selection logic enables 3 operating modes:
• 4-quadrant operation
• Ramp time call-ups
• Ramp time "t5"
If the 4-quadrant operation is active (external 24 V input signal "4Q"), the electronics
automatically detects the command value polarity and the command value modifica-
tion and attributes a ramp time to the current signal state.
Dependent on the signal state, one out of 4 ramp times is selected:
• Ramp up, positive (ramp potentiometer "t1")
• Ramp down, positive (ramp potentiometer "t2")
• Ramp up, negative (ramp potentiometer "t3")
• Ramp down, negative (ramp potentiometer "t4")
The 4-quadrant operation has a higher priority than all ramp time call-ups. While
a signal change is taking place, the LED attributed to the current ramp time is on.
The LEDs are on the front plate directly next to the associated potentiometer.
If the ramp times are very short, you will not be able to perceive the flashing of
the LEDs.
If the 4-quadrant operation is active, the LED "4Q" on the front plate is illuminated.
If the 4-quadrant operation is not active, 4 ramp times can be called up with any
call-up signal (24 V input). Only 1 call-up can be operated at the same time. If several
call-ups are operated simultaneously, call-up "1" has the lowest priority and call-
up "4" has the highest priority.
Each called-up ramp time is indicated via a yellow LED. The LED is on the front plate,
directly next to the associated potentiometer.
Ramp time "t5" is always valid, if neither the 4-quadrant operation nor a ramp time
call-up are enabled.
5.2.7

Characteristic curve generator [10]

After the ramp generator the command value signal is sent to the characteristic curve
generator. You can use this feature to separately adjust the step level and the maxi-
mum values for positive and negative signals to meet the hydraulic requirements.
The actual development of the characteristic curve through the zero point is not
stepped but linear.
In the condition as supplied, the characteristic curve generator is pre-set. If the jump-
ers J7, J8 and J9 are plugged, the output characteristic curve is set to the 4WRZ-7X.
To control the 4WRA-2X valves, the jumpers J7, J8 and J9 must be unplugged.
• You can use the jumper "J4" to switch the step function on (J4 = open) or off
(J4 = closed).
Information on this product
RE 30110-B/11.2012, VT-VSPA2-1-2X/V0/T., Bosch Rexroth AG
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