VLT ® 2900 Series Power and earth terminals must be tightened with the following torques: Tightening Torque, Power Terminals In lifting/lowering applications you need to be able to control an electromagnetic brake. The brake is con- trolled using a relay output or digital output (terminal 46). The output must be kept closed (voltage-free) for the period of time during which the frequency convert- er is not able to 'support' the motor, for example due to the load being too great. Select Mechanical brake control in parameter 323 or 341 for applications with an electromagnetic brake. When the output frequency exceeds the brake cut out value set in par.
138, the brake is released if the motor current exceeds the preset value in parameter 140. The brake is engaged when the output frequency is less than the brake engaging frequency, which is set in par. 139. If the frequency converter is placed at alarm status or in an overvoltage situation the mechanical brake is cut in immediately. Control of mechanical brake NB! This application is only for lifting/lowering without a counterbalance. Access to control terminals All terminals to the control cables are located under- neath the protective plate on the front of the frequency converter. Remove the protective plate by pulling it downwards (see drawing).
66 MG.29.A3.02 - VLT ® is a registered Danfoss trademark VLT Terminals Torque [Nm] 2903- 2975 Power mains brake 0.5-0.6 Earth 2-3 2980- 2982 Power mains brake 1.2-1.5 Earth 2-3