Product Description:

The SM10/20-T/A is an AC inverter module produced by Bosch Rexroth Indramat within the SM AC Inverters series. The unit converts a fixed DC bus supply into variable-frequency, variable-voltage output so that induction or synchronous motors can be regulated in automated machinery and material-handling lines. It receives enabling commands through a 24 VDC logic interface and reports ready status with a dry contact. This arrangement lets the inverter serve as the power conversion stage between the DC link and the motor windings during controlled operation.

Its power stage is rated for a continuous motor phase current of 10 A, while transient overloads up to 20 A are accepted for two seconds to accelerate heavy loads. The internal control loop tracks speed across a range of 1:10000, using a tacho feedback scale of 2.7 V per 1000 rpm to maintain resolution at very low frequencies. A stiff link to the intermediate circuit is provided by the 520 VDC bus, and a current derating of 1.2 % per K applies above the nominal reference temperature. Command inputs present 10 kΩ impedance, so common motion controllers can drive the inverter without excessive loading. Steady demand from the auxiliary supply remains limited to 20 W.

The module is intended for cabinet integration rather than exposed installation. The electronics remain operational up to +55 °C, and above this point the load must be reduced in line with the stated derating curve. Altitude is limited to 1000 m AMSL so cooling performance is maintained, and heat loss inside the panel peaks at 90 W, which is removed by a 24 VDC fan that draws 100 mA. Protection is classified as IP00, so all live parts require a protective housing. Additional 24 VDC enable lines and a ready contact rated at 1 A allow the drive to interlock with external safety relays.