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Troubleshooting Whelen HDACF 14/28

Tcheairs

Well Known Member
No strobes firing even after engine start. 13.5v charge from alternator.

Checked continuity of circuit from CB thru switch to controller. Have 12V at controller from ships battery but no fire. Vic Syracuse verified controller working during annual by "hot wiring" power to the control unit. I don't know exactly how he went about doing that but I have seen photos and videos of a "power unit" hooked up to the controller and "jumped" as per the Whelen install guide.

2 questions. Should I use the jumper port (the input just to the right of the main power input port) to test the system further and what power source can I use to supply a full 14+ volts to the unit. The manual says it might take 14v to fire the unit on the ground.

Thanks
 
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These things are certified and have serious doubt that a full 14V is required to make them work. Can think of many situations where ships power could be between 13-14.5 volts and doubt the FAA would allow a product that stopped working below 14V, as that is very non standard. Makes no sense that the unit needs 14V on the ground beyond the fact that at startup they pull a good bit of juice to charge the capacitors. I have whelen power packs on my 6 and have tested them on the ground several times and had no issue getting flashes at less than 13V.

Many components that can go bad in that box and have no guidance on how to test. However, I would pull the light wires off and test with only one attached at a time and see what happens. This will help to sort out any shorts in the lamp side.
 
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Also read the manual. Believe that the second port is the trigger. If memory serves, you send 12V to one port and the other is the on/off trigger. If the supply line is also your on/off control, then you need a jumper on the trigger. PLEASE do not trust this recollection. just a nudge to review the manual and insure your issue is not a simple wiring error. Issue couild be as simple as a loose or corroded pin on the trigger jumper.
 
Thanks, I'm going to take another look today. Don't recall that the jumper is installed in the 2nd port. I thought (according to the manual) that the jumper port was for testing only. I'll read it again.
 
Just one more question in this thread. I'm thinking about making a pigtail to supply the control unit with an external 12v source since I suspect a problem between the panel and the controller. This is to determine whether or not the controller is working.

I plan to fabricate a pigtail with a 10a inline fuse for protection, but the wires supplying the controller are very small and the manual says that the controller uses up to 7.5 amps.

Does anyone see a potential issue with this troubleshooting idea?

Thanks
 
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