The ABB ACS850 - 04 drive modules' RDCU drive control unit has multiple functions. In control signal processing and transmission, it receives external control signals via digital and analogue input interfaces to control inverter operation and sends status and control signals to external devices through digital and analogue output interfaces. For power management, it can be powered by the inverter's power board, IGBT power module or an external 24V DC power supply, with stable input voltage and current requirements. The communication function includes high - speed data transmission via fibre - optic connection following the ABB PPCS protocol and supports various fieldbus communications. It works closely with the motor control and I/O board and the control panel in the inverter system. The manual also provides safety instructions, including warnings about conditions that could cause injury or equipment damage, warning symbols, and electrical safety rules for installation and maintenance such as only allowing qualified electricians, waiting for capacitor discharge, and avoiding working on live equipment.
• Do not make any insulation or voltage withstand tests on the drive or drive
modules.
Note:
• The motor cable terminals on the drive are at a dangerously high voltage when
the input power is on, regardless of whether the motor is running or not.
• The brake control terminals (UDC+, UDC-, R+ and R- terminals) carry a
dangerous DC voltage (over 500 V).
• Depending on the external wiring, dangerous voltages (115 V, 220 V or 230 V)
may be present on the terminals of relay outputs (X2) or Safe torque off (X6).
• The Safe torque off function does not remove the voltage from the main and
auxiliary circuits.
