I am attempting to use a model 090413 (ASAIN booc9uufhc) 15 amp unit to run LED cabin lighting on our boat at a constant 12 volts. The voltage on a 12V boat varies dramatically from about 12.5 to as much as 14.5 when the large charger for the battery bank is in the bulk charge mode of operation. I connected the DROK device between the breaker/switch for the aft cabin lighting circuit, and the large wire which then feeds the three individual light switches in the cabin. Total load for the three (homemade) light arrays is about 10 amps. When I installed the DROK unit and attempted to adjust the voltage with the small screw rheostat, no change could be detected (I was using a voltmeter to check for changes. The unit is stuck at about 12.8 volts on the output side. Both of the negative terminals on the Drok are attached to the DC ground circuit of the boat. I am unable to understand why the unit will not control the output voltage. And by the way, DROK would be smart if they provided an instruction sheet as to how to hook up and adjust these units. I am not an electronics expert, and had some difficulty understanding which terminal to connect to what. (I assumed the “input” positive connects to the boat battery, and the output positive would go to the lighting circuit…in this case).

A final question…is it correct that the Drok unit I have purchased is the most appropriate for this application? Not that I could purchase individual LED bulbs, but preferred to make my own arrays in order to better direct the lighting for each switch. I purchased the DROK device because the large voltage swings on the boat were causing premature failures of the LED strip lighting.