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 AIP171 Fault-tolerant 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 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 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

 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 changes. Fuse F70 is a protection fuse connected in series with the AC input of the power supply unit. The power supply unit provides the DC voltages 30 V, 15 V, 5 V and -15 V to the control electronics. Auxiliary voltages can be measured by means of a multimeter from the terminal X70 (see the layout).

There are two possible configurations for two field exciters: - one SDCS-FEX-2 and one external field exciter (DCF503-0050, DCF504-0050 or 3 phase field exciter) or - two external field exciter units (DCF503-0050, DCF504-0050 or 3 phase field exciter). If a SDCS-FEX-2 is used, it will be recognized as the first field exciter by the software and therefore, it cannot be coded as a second one. If a DCF503/ 504-0050 is used as the first or the second field exciter it must be coded according to the table below.Procedure for code changing of the DCS 503/504: • Switch off the units voltage supply • Set the appropriate connection according the table • Initialization through switch on the electronics supply voltage

 Power section

 If a DCF503-0050 is in use two diode-thyristor modules are arranged as a half-controlled singlephase rectifier. If a DCS504-0050 is in use four thyristor-thyristor modules are arranged as a fully-controlled single-phase rectifier. The anodes of the two diodes (anodes / cathodes of the thyristors) are not connected directly to each other as usual; they are now connected to the ends of the 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 free wheeling function needed e.g. during network failure is ”build in” because of the diodes, if the half-controlled version is in use. If the fully-controlled version is used the free wheeling function is realized by using the thyristors in diode mode, controlled by the micro controller.