What is parallel mode in power supplies?

Parallel mode distributes the current equally between power supplies that are connected in parallel. In parallel mode, the output voltage is regulated so that at no load it is around 5% higher than at nominal load. 

The main requirement for equal distribution of the load current is that all the power supplies are set to less than ±100 mV at no load or still have their factory settings.

In many PULS power supplies, parallel mode can be activated with a single use/parallel use jumper on the front of the device. A jumper that is not plugged in sets the power supply to single use. The factory setting is single use.