POWr Popup is set by default to open one second after someone lands on a page. However, if you use an upgraded version of POWr Popup, you have more options of when to trigger the popup. You can set this in the Design menu under General.
Time Delay - popup will appear after a specified time delay. Use the slider to set your delay.
Exit Page - popup will appear when visitor moves to leave the page, either by closing the browser, or clicking the Back button.
Visitor Click - popup will appear when visitor clicks something on your page. To set this up, you must add the plugin to the page, then wrap a piece of text, button, or image in a special CSS class, like this...
<span class="trigger-popup">your text, button, or image here</span>