Product Description:

The VM7.5/BE-G is an amplifier drive module produced by Bosch Rexroth Indramat as part of the VM Amplifier Drives series. Installed between the line transformer and a servo controller, the device rectifies, filters, and monitors supply power for multi-axis systems used in packaging lines, machine tools, and material-handling cells. Its purpose is to maintain stable bus voltage, dissipate regenerated energy, and furnish auxiliary voltages so that downstream inverters can modulate motor speed with repeatable accuracy.

Designed for single-phase operation, the drive accepts a nominal input of 230 V AC and rectifies it to a DC link held at 325 V DC under nominal load conditions. Without an auxiliary fan, it supports a continuous power output of 0.8 kW. With forced cooling, the thermal path supports a maximum continuous rating of 7.5 kW, allowing the same cabinet footprint to serve heavier axes. The control electronics are maintained from an external feed of 24 V DC, which keeps diagnostic LEDs and fault processing active during emergency-stop power removal. A digital logic rail of +5 V and a negative analog rail of -15 V are internally derived from this supply to bias sensors and command circuits.

Energy returned from rapid deceleration is shunted into the ballast resistor; the element switches on at 380 V DC and disconnects at 370 V DC to protect the capacitors from overvoltage. The positive analog reference of +15 V supports velocity setpoints, while the companion negative rail balances differential inputs for better noise immunity in the command section. The unit has an IP20 finger-safe cover and complies with climate class 3K3 for 5% to 85% relative humidity. The assembly weighs 1.7 kg, and auxiliary relays use Btb2 (50 V, 100 mA, 10 VA) and Btbent (30 V, 6 A) contact limits to report drive-ready status or fault conditions to higher-level controllers.