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Spare parts spare parts, the DCS control system of PLC system and the robot system spare parts,

Brand advantage: Allen Bradley, BentlyNevada, ABB, Emerson Ovation, Honeywell DCS, Rockwell ICS Triplex, FOXBORO, Schneider PLC, GE Fanuc, Motorola, HIMA, TRICONEX, Prosoft etc. Various kinds of imported industrial parts

B&R 7DI140.70 Digital quantity input module

Neither the ON nor the RUN command is effective in this phase. Only upon reaching the minimum speed, can the drive be restarted with the rising edges of the ON and the RUN command. Field heating The field heating starts 10 s after ON command (without RUN command). The field heating will switch on automatically 10 s after the drive is stopped (RUN=0) and the actual speed is lower than Zero Speed Lev (5.15). When the drive starts again (RUN=1) the drive will switch over to nominal field current.

Software functions are described in the context of the individual parameters (see parameter list). Special functions which require an comprehensive parameterization or no parameterization and the service procedures are described below. 4.5.1 Monitoring the Mains Voltage and Auto Reclosing The DCS 400’s mains voltage monitoring feature has been implemented in a new, and hitherto unusual manner. It permits simple parameterisation, and assures dependable operation. Usually, with digital power converters, parameter values are entered for mains voltage and tolerance thresholds. This is not the case with the DCS 400, whose power section can be operated on a mains supply voltage of 230V…500V without any further parameter settings.

Regulator functions

There is a physical correlation between the motor voltage and the requisite mains voltage, and between the specified mains voltage and the resultant maximum motor voltage. While for drives operating purely in motoring mode, this causal relationship is non-critical, except that if the mains voltage fluctuates the motor’s output and speed will also fluctuate, in the case of drives operating in regenerative mode reliable operation is assured only as long as the mains voltage is stable and remains in the correct ratio to the motor voltage. The minimum permissible mains voltage is computed from the Armature Voltage Nominal (1.02) (Ua) parameter. If the voltage drops below this computed level, a controlled drive shutdown will be executed, followed by the error message F09-MainsUndervoltage.

The advantages of this principle are that • The lower the motor voltage is in relation to the mains voltage, the greater are the permissible mains voltage fluctuations. “Soft” networks cause fewer disturbances in the drive. • Drives operating in regenerative mode are better protected against shoot-through. This means that fuse tripping and thyristor destruction are largely prevented. • the appropriate mains undervoltage detection function is selected and activated by the automatic detection feature of a 2Q/4Q drive. • no parameter setting for the mains voltage is required. • it is impossible to make a parameter setting for unsafe operation. • the drive thus remains simple and safe