R911253851
The Bosch Rexroth R911253851 (MDD112D-N-020-N2L-180GA0) is a digital servo motor with a standard design housing. It utilizes two cooling methods: convection cooling, where ambient air flows over the motor housing and surface cooling, which involves the flow of air from a fan or blower over the motor surface. Surface cooling provides superior heat dissipation, allowing the motor to generate higher output torque and current. With natural convection, the continuous torque at standstill is 38 Nm and the continuous current is 43.8 Amps. With surface cooling, these values increase to 57 Nm and 65.8 Amps respectively. The thermal time constant is shorter with surface cooling, clocking in at 90 minutes compared to 120 minutes with natural convection.
This R911253851 (MDD112D-N-020-N2L-180GA0) model lacks a holding brake and weighs 59 kilograms. It is capable of a theoretical maximum torque of 134.8 Nm, and a peak motor current of 166.4 Amps. Its torque constant and windings resistance at 20 degrees Celsius are 0.87 Nm/A and 0.18 Ohms respectively. Other specs include windings inductance of 2.7 millihenry, rated speed of 2000 RPM and a centering diameter of 180 millimeters. The motor operates optimally in 0 to 45 degrees Celsius, while storage temperatures should remain between -20 and 80 degrees Celsius. The device has a plain shaft design, power connection on side A, digital servo feedback and an ideal installation elevation of up to 1000 meters above sea level.
