Emerson 200I/48-NT5C05C user manual Rectifier parallel operation, Slope sharing SLS

Models: 200I/48-NT5C05C

1 62
Download 62 pages 12.8 Kb
Page 38
Image 38

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 -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 ) 200

UM5C05C P0745680 Standard 6.00 October 2001

Emerson Energy Systems

Page 38
Image 38
Emerson 200I/48-NT5C05C user manual Rectifier parallel operation, Slope sharing SLS