Afag SREH-50-IOL, Assembly And Operating Instructions Manual

Page: 36 / 52

Installation, assembly and setting
36 – 52 Assembly instructions EN

SREH-50-IOL
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Date 17.06.2022
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Version 1.0
6.4.2 Energy supply Drive
A regulated power supply unit is required to power the drive. The power supply
unit must provide the power required at the output of the rotary module. The
design of the power supply unit is highly dependent on the application - e.g., the
moving load - and the required acceleration.
MIN. TYPE MAX.
Voltage 16 24 32 VDC
Current: - -
4.5 A peak
Tab. 1 Energy supply
Voltages below 24V reduce the maximum speed of the drive. A reduced
current limit the maximum acceleration.
6.4.3 Generative operation
In applications with large loads and trajectories with maximum acceleration
and/or speed, energy is fed back into the drive supply circuit. This may increase
the voltage in the power supply circuit by up to 20 VDC, which may damage/shut
down the power supply, shut down the SREH-50-IOL and possibly damage
other equipment connected to the same power supply circuit.
The SREH-50-IOL smart rotary module has internal monitoring of the drive
supply voltage. If the measured voltage leaves the range, the output stage is
switched off. The range can be set between 16V and 32V via IO-Link (  Chapter
6.4.2).
If the power supply unit is not regenerative, damage can be prevented with a
diode at the output of the power supply unit (see [5], Fig. 17). The diode must
be dimensioned according to the expected voltage and currents.
Industrial power supplies are usually regenerative, i.e. the voltage at their output
may rise to a certain limit without the power supply switching off or being
damaged. This data can be found in the data sheet of the power supply unit.
To prevent an excessive increase in voltage, it may therefore be necessary to
provide one or more external measures (Fig. 17).
The most energy-efficient method (Fig. 17) is to buffer the entire energy in
capacitors - either in the power supply unit's internal output capacitance
𝐶𝐶
𝑖𝑖𝑖𝑖𝑖𝑖
(see [3], Fig. 17) or in an additional bus capacitance
𝐶𝐶
𝑒𝑒𝑒𝑒𝑖𝑖
(see [4], Fig. 17). The
power supply unit's internal output capacity can be found in the power supply
unit's data sheet.
Table 1 gives a recommendation for the required capacity
𝐶𝐶
𝑖𝑖𝑖𝑖𝑖𝑖
+ 𝐶𝐶
𝑒𝑒𝑒𝑒𝑖𝑖
depending
on the load. The basis for this recommendation is the assumption of a pivoting
movement with maximum speed and deceleration and a regeneration of 50% of
the mechanical energy.
For applications with lower dynamics, a lower bus capacity can be provided.