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

Products are widely used in metallurgy, petroleum, glass, aluminum manufacturing, petrochemical industry, coal mine, papermaking, printing, textile printing and dyeing, machinery, electronics, automobile manufacturing, tobacco, plastics machinery, electric power, water conservancy, water treatment/environmental protection, municipal engineering, boiler heating, energy, power transmission and distribution and so on.

YOKOGAWA AIP591 Transceiver module

DCF503A / DCF504A is based on a new CPU type compared to the DCF503/DCF504. The half controlled field exciter unit DCF503A-0050 consists of the SDCS-FEX-32A board, two thyristor/diode power modules and auxiliaries (power supply, line choke). The full controlled field exciter unit DCF504A-0050 consists of the SDCS-FEX-31A 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).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 -scaled to measurement range- are adapted by the board itself depending on the setting of the nominal motor field current. The current signal can be measured

Field exciter configurations 

The data exchange between the SDCS-CON-x and the field exciter SDCS-FEX-2 or the DCF503/504- 0050 is done via a RS485 serial link, which is able to work not as a point to point connection, but as a bus structure. This link is used to transfer references, actual values and settings for up to two field exciter units. The drive software located on the SDCS-CON-x board consists of two field supply modules. One of them is already connected to the EMF controller to allow the motor running in all points of his motor diagram. The other one is accessible via the field current reference. The RS485 interface works with a screened twowire cable. The allowed length is 5 m. The wires have to be connected to the terminals X2:1 and X2:2 and the screen to X2:3. Typical application of this kind is two DC motors connected to one converter. The load sharing can be done by means of adjusting the excitation current of the second DC-motor.

Diagnosis The aramarure converter receives via serial link the sum of all faults in "Fex status bit". A more detailed error code is given on the seven segment display of DCF 503A/ DCF 504A.

Electronic power supply

 There is a power supply unit on the board. Supply is connected at terminal X3. The rated AC voltages 115 V and 230 V can be applied without any modification. The power supply unit provides the DC voltages 30 V, 15 V, 5 V and -15 V to the control electronics. Voltages can be measured by means of a multimeter from the terminal X70 (see the layout). In addition the power supply generates 5 V for galvanic isolated RS485 communication drivers. This voltages can be measured at terminals X100/X101.

The control unit includes the following main blocks: - Micro controller H8 for control 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 FlashPROM memory. This software contains a PI current controller Fault/reset logic Synchronization and PLL function Bridge reversal function (only DCF 504A)The setting and updating of all control parameters are set from armature converter via RS485 interface. Actual current, field current reference, control and status bit are cyclic sent via RS 485 communication. The field exciter is equipped with an auto-scaling function of burden resistor based on the nominal field current of the motor.