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Tman
04-05-2014, 10:55 PM
A quick question , does Alpriority have polarity protection , i guess so , just need a confirmation.

I know that most rd has it.

dinkydi
04-05-2014, 11:07 PM
good question, arent sure, but i think its always best to start the eng and the power ur cm's on, i also kill mine before switch off, ba on our oz forum built a small diagram for a simple circuit protector, but the are other things on ebay , ba on our forum, knows of em

shanetrainST
04-05-2014, 11:25 PM
I hope it has, would not like to try it out.
There is always one in a crowd that attempts to put the black wire to the +12vdc.
As much as I hate to say it cause I sometime ignore it, always read of the manual and understand wiring diagram before installing.

Lucky225
04-05-2014, 11:36 PM
I hate products that don't have polarity protection, a simple bridge rectifier circuit will ensure polarity is sent correctly to the circuit and isn't very expensive to add.

Tman
04-06-2014, 09:05 AM
I hate products that don't have polarity protection, a simple bridge rectifier circuit will ensure polarity is sent correctly to the circuit and isn't very expensive to add.

A bridge will do , a 5 cents diode will also do !

I know the V-1 has , so the Redline , tested and confirmed....they simply dont power-up .

BestRadarDetectors
04-06-2014, 09:21 AM
I am not about to test my ALP but if you do not know that RED = +12V and Black = Ground you really should not be installing these yourself.
Manual is also very clear on which is Positive & Ground.

radargeek
04-06-2014, 10:11 AM
The ALP seems well designed, hopefully they included a diode or MOSFET for reverse polarity protection, since mistakes do happen. Who wants to test one to find out? :)

FWIW, I included reverse polarity protection in my latest autokill design. I haven't dared to try it yet though. :eek: Guess I should sometime, on my development prototype anyway.

RedRocket
04-06-2014, 10:24 AM
FWIW, I included reverse polarity protection in my latest autokill design. I haven't dared to try it yet though. :eek: Guess I should sometime, on my development prototype anyway.
Play it safe even on the Proto...put low-amperage (depending on "I" drain) Fast-Blo fuse on the "Load" side after protect diode,just in case. :dejection:

radargeek
04-06-2014, 11:31 AM
Play it safe even on the Proto...put low-amperage (depending on "I" drain) Fast-Blo fuse on the "Load" side after protect diode,just in case. :dejection:Whenever I am doing any critical power-up test where there's a possibility of letting the smoke out, I power it up with a somewhat weak 9 volt battery first. That provides enough overcurrent protection to hopefully avoid any real damage.

I'll hook my multimeter up inline to measure current when I do a reverse polarity test on my prototype with the 9V battery. If it works properly, there should be no current flow.

BestRadarDetectors
04-08-2014, 05:16 PM
Not that I would suggest you play with reversing the wires but I did speak with Engineering and they confirmed the ALP does indeed have Polarity Protection.