I couldn't put my hand on my copy of the DBS-1000 User Manual (gawd but I need to re-vamp my filing system) so I went to the Helix page and pulled the copy of the manual there.

Here's a direct quote from page 2...

Connect the heaters. If more than three outlets are needed, an adapter block, or standard power strip with a
ground adapter can be plugged into one of the Controller’s outlets. Avoid using plug strip’s with built-in surge
protectors as these may produce a short circuit if a surge occurs and may cause an internal fuse to blow or they can
cause errors to pop up. Each System has built-in surge protection ability and there is a customer replaceable 6 amp
“fast-acting fuse” in the system to protect it against heater/wiring failures or short circuits to the controller’s output.
The fuse will “blow” if more than 500 watts of heaters/lights are plugged in or if there is faulty electrical wiring
on the heaters.
*their bold and underline not mine*

You can find the entire User Manual for the DBS-1000 by going to this page and clicking the link "User Guide and Specifications" at the the bottom of that page (pdf format).

http://www.helixcontrols.com/DBS1000_Info.htm