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Hardware 
3ADW000197R0101 DCS800-R Sel e a
 Hint: 
The above mentioned monitoring signal should be read by the PLC (programmable 
logic controller) or connected to an input (one of the 2 inputs, which have a fast 
update time) of the DCS800-R0x electronics (as indicated above) to handle the 
COASTING function of the converter. If the supply voltage is o.k. the converter can 
be released by the PLC. If the supply voltage drops below the threshold, the signal 
level changes at X2:1 /2. The COASTING function should be activated, which will 
block the controllers of the converter and force the current to zero as fast as possi-
ble for safety reasons. To avoid a blocking and unblocking condition the “power ok” 
signal should be latched off.  
The PLC should release the system depending on other starting conditions.   
 
Functionality 
  Electrical characteristics of the SDCS-REB-2 
-  Current requirement for +24 V is 100 mA 
-  Current requirement for +48 V is 0.4 A for each parallel connected thyristor; if 
there are 4 parallel thyristors the requirement is about 1.6 A 
-  The power supply should contain sufficient amount of capacitance so that  
+
10% secondary voltage tolerance is not exceeded due to voltage ripple; 0 V 
terminal of the electronics on SDCS-REB-2 is connected to the six mounting 
holes on the board. Therefore it is grounded.  
 
At the input plug connectors X613 and X713, firing pulse signals 1 to 6 are re-
ceived, and the current-direction signals SR1 and SR2 as well. The board ampli-
fies these signals and distributes them to 8 plug connectors named X11 to X42. 
The current direction signal SR1 is assigned to plug connectors Xx1, and current 
direction signal SR2 to plug connectors Xx2. 
 
Fastening 
  The SDCS-REB-2 board has six M4 mounting holes. All of them must be grounded 
using metal stand-offs (see figure Layout of the SDCS-REB-2 board below).