antdickens 0 Posted February 1, 2005 I have some 12volt cameras with 12 volt heaters in the housings which potentially need 2 amps when the heaters are on full Would i be able to use a 12v regulated power supply which has 4 1 amp outputs and pair two of the outputs giving two 2 amp outputs? or is this not recommended Thanks in advance Share this post Link to post Share on other sites
Cooperman 0 Posted February 1, 2005 antdickens What your are trying to do (current sharing) will work in principle, but ... some heaters will pull more current when they first start up, and as you are looking at a total load of 4 amps against a 4 amp rated output, there is nothing in reserve. Depending on the build quality, the PSU may well be operating on its limit, and this may significantly reduce its life expectancy. If I'm asked to spec a PSU, I generally try and under run a unit by at least 30%, so that it's never being worked too hard. If at all possible, I would always prefer to keep the heater and camera PSU's seperate, particularly as the camera is the more critical piece of kit. Also you don't need a regulated supply for a heater; unregulated is fine. If you lose a heater supply for a couple of days, it's generally no big deal, but if the PSU fails and your cameras go down, that can be more of a problem Share this post Link to post Share on other sites
VST_Man 1 Posted February 1, 2005 you should be able to change the fuses to a 2 amp and only use two of the four outputs (assuming you have only one AC transformer in the PS) If the PS is rated at 4 amps, that's all your going to get from it. Total all of your amp draws and do not exceed. ANTDICKENS is right, you going to pull at 100% which will be a factor in how efficient the PS works. Good luck. Share this post Link to post Share on other sites
Cooperman 0 Posted February 1, 2005 quote VST_Man you should be able to change the fuses to a 2 amp and only use two of the four outputs The only obvious problem here might be if the design of the PSU uses four 1 amp regulators, one on each output. If you change the fuse on one rail to 2 amp, the regulator will give out before the fuse. However, if the PSU has a 4 amp regulator with the output split to four fused connections, then the fuse change would not present any problem. Share this post Link to post Share on other sites
