The main products

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

07KT98 GJR5253100R4278 Logic module

The control unit includes the following main blocks: - Micro controller 80C198 for controlling and firing - Actual DC current measurement with an AC current transformer. - RS485 interface to the converter's controller board SDCS-CON-x. The software for the field current control is stored in the ROM memory of the 80C198. The control is done by using a PI structure for the current controller. All parameters needed for the control or for scaling reasons (selection of burden resistors) are stored in the non-volatile memory of the armature converter and transferred to the field controller during each initializing process via the RS485 link. The Node number is always fix coded to Node number = 1. The output Iact represents the actual field current, which is measured via the AC transformer, then rectified and transferred into a voltage signal with burden resistors. The burden resistors, as mentioned before, are adapted by the board itself depending on the setting of the nominal field current of the motor (see list before). The resulting burden voltage can be measured at test terminals beside X14:. The 2.2 K
resistor allows a short circuit at the terminals; the external measuring device should have an internal resistance higher than 1M
. The terminal row X20: is used for test purposes.

Power section 

Two diode-thyristor modules are arranged as a half-controlled single-phase rectifier. The anodes of the two diodes are not connected directly to each other as usual; they are now connected to the ends of the four turn primary winding of the current transformer. The centre tap is the negative output of the rectifier. Thus it is possible to measure the DC current with an AC current transformer. A MOV (Metal Oxide Varistor) protects the AC input against voltage spikes from the external source. Another MOV protects the DC output against voltage surges which can be caused by the field winding of a DC machine.The half controlled field exciter unit DCF503-0050 consists of the SDCS-FEX-32 board, two thyristor/ diode power modules and auxiliaries (power supply, line choke). The fully controlled field exciter unit DCF504-0050 consists of the SDCS-FEX-31 board, four anti-parallel thyristor/ thyristor power modules and the same auxiliaries.The control is structured similar to the SDCS-FEX2 field supply. A micro controller is used for controlling and firing. The DC current is measured by using an AC current transformer (same configuration than at SDCS-FEX-2).