38 Functional description
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
±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 ) 200
UM5C05C P0745680 Standard 6.00 October 2001 | Emerson Energy Systems |