Xantrex Technology XFR 2800 manual Configuring, Parallel, Supplies for

Local Operation

Using Multiple Supplies

sum of the maximum voltages of each supply (add voltmeter readings, to a maximum of 600 V). The maximum allowable current for a series string of power supplies is the output current of a single supply in the string.

	Figure 3.2 Series Operation of Multiple Supplies
Configuring	Use parallel operation to obtain a higher current through a single output using two or
Multiple	more supplies. Set all of the OVP setpoints to maximum. (See “Using Over Voltage
Supplies for	Protection (OVP)” on page 61.) Set all of the outputs to the same voltage before
Parallel	connecting the positive (+) output terminals and negative (–) output terminals in
Operation	parallel. See Figure 3.3. The total current available is the sum of the maximum
	currents of each supply.
	When operating multiple supplies in parallel, the operating mode of each supply
	depends on the load current being drawn. For example, with two 40 V, 70 A power
	supplies operating in parallel with a 100 A load, one supply operates in constant
	current mode supplying 70 A and the other supply operates in voltage mode
	supplying the remaining 30 A. The level of current sharing between units depends
	on how accurately the output voltages are matched.
	Note:If you do not fix the OVP setpoints at maximum, the OVP circuit may trip on
	one unit, reducing the current available to the load.

66 Operating Manual for XFR 2.8kW Series Power Supply