Emerson 200I/48-NT5C05C Manuel D’Utilisation

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38   Functional description 
UM5C05C   P0745680   Standard 6.00   October 2001 
Emerson Energy Systems 
The rectifier can be started when it is connected across a completely 
discharged battery without requiring human intervention or operating 
protective devices. A transition from constant voltage operation to 
constant current operation and from constant current operation to constant 
voltage operation occurs automatically, as determined by the output 
current. The current limiting circuit is functional in float and equalize 
modes. 
4.2.8.  Rectifier parallel operation 
The rectifier can operate in parallel with other rectifiers having similar 
output characteristics. It shares the total load in proportion to its output 
rating.
 
Two methods for sharing load current are available : 
• 
Slope sharing 
• 
Forced sharing 
Selecting either mode is done by setting the two bottom DIP switches, 
SLS / FS, located on the front panel.
 
The rectifier is factory set to the slope 
sharing mode. 
Slope sharing ( SLS ) 
When both bottom DIP switches are set to the SLS position, conventional 
load sharing is achieved through a -300 mV slope on the output voltage of 
the rectifier, from no load to full load. This mode should be used when 
rectifiers from different manufacturers are not all equipped with the forced 
load-sharing feature. In this mode, the units will share the load within 
±
10% of their maximum output rating. 
To accurately preset the float voltage of the rectifier, its current in the plant 
environment must be predicted and the preset output floating voltage must 
be calculated using the formula found below. In the formula, 0.8 volts is 
added to the float voltage to compensate for an internal voltage drop when 
the rectifier dc breaker is put in the ON position. 
V ( preset ) = Vo ( desired ) + 0.8 V + ( Io ( running ) x 300 mV ) 
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