FSequence IPM Owners Guide.book Page 36 Thursday, October 6, 2011 3:33 PM

Freedom Sequence Operational Concepts

DC Load Shedding

The Freedom Sequence continuously monitors the battery voltage and compares it against the four voltage settings to set the trigger and clear the trigger of a DC relay on a High Battery Voltage setpoint as well as a Low Battery Voltage setpoint.

The Freedom Sequence power manager measures the battery voltage from the DC power terminals of the auxiliary connector port. If Xantrex devices exist on the Xanbus network, the power manager will use the battery voltage reported by these devices in a preferential order by source as:

Battery monitor >> charge controller >> inverter/charger

The Trigger Set and Trigger Clear are absolute setpoints and don’t take into account the duration for how long the battery voltage will be low before triggering the DC relay. Each of the DC relays has a N/O and N/C contact point which will toggle to Closed and Open positions respectively when a DC relay is triggered.

Using DC Relay to control AC load circuits

The DC Relays can also be used to shed AC load circuits if a DC Relay is used to control the external AC Relay. This can be done by going to the DC Relay configuration menu and selecting its association to Line1.

When the association is changed to Line1, all the configuration fields for the DC relay will change to those found for the AC relay, allowing to define Priority, Reconnect MRGN, Gen Soft-Startoption, et cetera.

The Freedom Sequence does not have a current sensor to allow continuous monitoring of the current draw by the load circuit that this DC relay controls and therefore, it will show as N/A on the SCP.

However, the Freedom Sequence automatically calculates the decrease in current achieved by disconnecting the AC load circuit that is indirectly controlled through this DC relay and shows it as Last-Load Shed current.

 

 

36

 

Freedom Sequence Intelligent Power Manager Owner’s Guide

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Page 46
Image 46
Xantrex Technology 809-0912 manual DC Load Shedding, Using DC Relay to control AC load circuits