R901276379 Rexroth DIGITAL CONTROL ELECTRONICS VT-HACD-3-2X/N-I-00/000

Input for digital position measurement systems (2 x SSI or 1 x incremental) 6 analog inputs, voltage (±10 V, 0…10 V) and current (4…20 mA) switchable via software, input resistance of AI1 > 10 MΩ 3 analog outputs, 1x switchable voltage (±10 V, 0…10 V) or current (0…20 mA, 4…20 mA), 2x voltage (±10 V) Various possible signal linking and switch-over options Enable input and OK output 8 digital inputs 7 digital outputs, configurable Parameterizable ramp function 32 blocks with command values, velocities and controller parameters Adjustment to hydraulic drive by means of area adjustment, characteristic curve correction, overlap compensation, residual velocity logic and zero point correction. +10 V reference voltage output Serial interface RS232 Up to 32 electronics can be interconnected for parameterization and diagnosis via the local bus
 

he VT-HACD-3-2X control electronics are a module for top hat rail mounting.

A microcontroller controls the entire process, makes adjustments, establishes connections and realizes the closed control loops. Data for configuration, command values and parameters are stored in a FLASH in a non-volatile form.

The BODAC PC program is used for the entire configuration and also for the parameterization and diagnosis. Besides the switches for address setting, the module is not equipped with any additional hardware switches. For the configuration, the HACD has to be connected to a PC via a serial interface (RS 232, 1:1 cable).

The configuration and thus the creation of applications are very simple – simply connect the pre-defined functional components. For this purpose, no programming knowledge is necessary.

A mode is available:

Structural editor

Own motion sequences can be established. For this purpose, 32 blocks are available.

Each block contains: Command value, ramp times, (velocity ±, acceleration ±) and controller parameters.

Blocks are activated by setting trigger conditions: Setting digital inputs, comparing signals with freely definable thresholds or expiry of waiting times.

Signal linking [6] [8] [17]

The HACD has various signal linking options both for the input and the output side, whereas 2 signals each can be linked. These are functions such as addition, subtraction, multiplication, division as well as minimum/maximum value generator, area ration and limiter:

+ = Addition: Z = X + Y

– = Subtraction: Z = X – Y

* = Multiplication: Z = X * Y / 100

/ = Division: Z = X / Y * 100

MIN = Minimum value generator: Z = MIN (X, Y)

MAX = Maximum value generator: Z = MAX (X, Y)

RATIO = Ratio input:

for RATIO >1: Z = X * RATIO – Y

for RATIO <1: Z = X – Y / RATIO

(e.g. area ratio for pressure differential measurement)

LIMIT = Signal limiter: Z = MIN (|X|, |Y|) * sign (X)

JUMP = Jump generator: Z = MAX (|X|, |Y|) * sign (X)

with Z … result

X … 1st signal

Y … 2nd signal

T1 Lag = Low pass filter

Analog I/O [1] [15]

The 6 analog inputs are switchable between ±10 V, 0…10 V, 0…20 mA by means of the software.

The analog output AO1 is switchable between ±10 V, 0…10 V, 0…20 mA and 4…20 mA by means of the software.

AO2 and AO3 are fixedly set to ±10 V.

The output is switched so that the whole range of the analog-digital converter is used.

Both working range and error detection can be defined for all analog inputs.

The analog outputs can be adjusted by means of amplification and offset.

Digital I/O [3] [16]

The HACD has 9 digital inputs and 8 digital outputs.

An input has the fix functionality Enable, a digital output the fixed functionality OK.

Further digital inputs are used for the triggering of blocks (see blocks and triggering).

The function of each digital output can be determined by the selection from a predefined list:

Command value = actual value Actual value higher or lower than the adjustable threshold Waiting time completed Ramp active internal flag set Error flag set Table completed Error status Block timeout Controller active Absolute value (actual value) < window Absolute value (command value) < window Incremental home position

Digital position measurement system

If VT-HACD-3-2X is used as control electronics, digital position measurement systems of type SSI or incremental can be used for actual value recording.

Limitations of use for the incremental encoder

The maximum frequency of the HACD incremental encoder input (fG) is 250 kHz. The maximum travel velocity of the drive, the resolution (res) of the encoder system used and the possible signal evaluation by EXE (interpolation and digitalizing electronics) determine the frequency.

Determination formulas

Encoder resolution at given maximum velocity:

Velocity at specified encoder resolution: