When a SmartPlug goes for a swim

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Ferrule use; re-wiring an Inverter

Here's an example of an inverter I recently re-wired using UL listed ABYC mandated ferrules. The strands are contained within the ferrule and this is what it looks like after installing and then removing/inspecting the 'crush' area...
 

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WD-40 won't get the salt out...but this will

Why call SmartPlug for advice? Does anybody really think that SmartPlug, if given all the facts, would truly advise to use their product after simply drying it off and squirting some WD40 on the contact surfaces?????

Obviously Smart Plug would have you replace the plug. Rather than spending $345 on a new Smart Plug, two options for the OP:

1) Soak the salty Smart Plug in de-ionized water for a few hours, shake it out, soak again, then blow out the remaining DI water with compressed air. De-Ionized water (a) does not conduct electricity and (b) is the most aggressive solvent for removing any kind of minerals (including salt) from any electrical/electronic assembly. WD-40 is then optional -- it will displace any remaining moisture.

2) Scrap the Smart-Plug and properly re-install an L5-30R on the Boat and an L5-30P on the cable using $0.50 cents worth of ferrules (mandated by ABYC anyway). Total parts cost less than $25.

Just my opinion...
 
Post 60 "Smart Plug" not so smart?
Why did you call it smartplug, the numbers given are not for smartplug
 
In post #60 are you saying that the Smart Plug caused 4 fires aboard your friends boats? It isn’t clear what you are saying.
 
I've replaced dozens of L5-30R connectors at the boat-end of shorepower cables for myself and for friends/clients. Before doing so I always remove and inspect the L5-30P inlet on the boat. In EVERY case, without exception, I have found the root cause is poor wiring termination inside the boat. The common defect is stranded wire stuffed into the inlet and the screw-clamp is directly in contact with the strands -- this is a 'code' violation -- ABYC requires a ferrule crimped on the end of any wire/cable that is terminated inside a screw-down type connector. When ferrules are not used, the strands 'squish', the connections invariably build up resistance over time, resistance creates heat in the blade(s), heat is conducted via the blade into the end of the shore-power cable and melts the plastic and/or causes a fire inside the boat. When an L5-30P inlet (or ANY boat-side AC inlet) s correctly wired using ABYC required ferrules, and recommended torque on the screws, the standard L5-30P is perfectly reliable and will provide safe service for the life of the boat. I am not a fan of 'Smart Plug' -- they are unnecessary, expensive and potentially mask other problems. After a recent heat-wave here in Minnesota I heard from four live-aboard marina mates that their cables were burned at the boat-end. All of them were burned because of miswiring inside the boat, the worst of them looked like this...a tragedy narrowly averted.

Don't the shore power inlets have integral pressure plates, driven by the screw, within the screw terminal, that compresses the strands without the damage caused by twisting down on top of them? If so, there is no reason for a ferrule, right?

Are these knock-off inlets or Marinco, etc?

I'm wondering if this might be a situation like, "Every car crash I've seen involves a car with seatbelts."

I'm not at all saying the assessment is incorrect. It is just that I'd want a different sample of inlets to be confident in it, i.e. random or balanced sample of good and bad cords and large enough for some certainty.
 
The Smart Plug has such plates for the screws. Rod Collins tested them and found them to be very good in regard to breaking off strands of wire.
 
I've replaced dozens of L5-30R connectors at the boat-end of shorepower cables for myself and for friends/clients. Before doing so I always remove and inspect the L5-30P inlet on the boat. In EVERY case, without exception, I have found the root cause is poor wiring termination inside the boat. The common defect is stranded wire stuffed into the inlet and the screw-clamp is directly in contact with the strands -- this is a 'code' violation -- ABYC requires a ferrule crimped on the end of any wire/cable that is terminated inside a screw-down type connector. When ferrules are not used, the strands 'squish', the connections invariably build up resistance over time, resistance creates heat in the blade(s), heat is conducted via the blade into the end of the shore-power cable and melts the plastic and/or causes a fire inside the boat. When an L5-30P inlet (or ANY boat-side AC inlet) s correctly wired using ABYC required ferrules, and recommended torque on the screws, the standard L5-30P is perfectly reliable and will provide safe service for the life of the boat. I am not a fan of 'Smart Plug' -- they are unnecessary, expensive and potentially mask other problems. After a recent heat-wave here in Minnesota I heard from four live-aboard marina mates that their cables were burned at the boat-end. All of them were burned because of miswiring inside the boat, the worst of them looked like this...a tragedy narrowly averted.
Good information. One minor point for those trying to get up to speed on terminology, I believe the end of the cable is the "P", or plug and the boat end is the "R" or receptacle. Do I have that correct?
Thanks.
 
IME, the exposed contacts are MALE and designated P. Doesnt matter the mounting config.
 
IME, the exposed contacts are MALE and designated P. Doesnt matter the mounting config.
On further thought he is correct. The receptacle is at the end of the plug (the powering end) and the plug is at the boat (the powered end). Typically it is the other way around but this is one of the few exceptions. Sorry for the confusion.
 
IME, the exposed contacts are MALE and designated P. Doesnt matter the mounting config.

True that. Lets make that 110%. :)

I other words, to be clear, I was wrong in my earlier post. I was thinking of the pedestal side, not the boat side.
 
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