Pin and sleeve connectors for 30a shore power

[thinwater]

Originally Posted by Nepidae

Compared to the 'standard' Marinco boat side receptacle and their cords the SmartPlug is the safest and to date I haven't seen anything else that comes close to the SmartPlug. I'm open if someone has a site reference for a better product....

It's probable you have not worked with pin and sleeve connectors, which have been common in industrial settings for decades. It seems like the more likely shift, since there is more experience with them and these are multiple manufacturers world-wide. They are in NEC and ABYC standards for higher amps and are available in smaller sizes. I'm sure there is some history regarding how this came to be and why twist lock is the standard in smaller sizes.



For now, wait and see. My guess is that I will be dead before the code changes.


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Serious question. If ABYC and NEC only approve specific styles, in black and white, where does that leave code approval of Smart plugs on the boat end? I find this confusing. We often hear of insurers not liking non-ABYC, non-NEC stuff on the boat, but this seems like an exception.

[wholybee]

Regardless of the type of cordset you have. Something every owner should know how to do. Provided you have accurate volt and amp meters on your boat.

When everything is "good" note the voltage. (Say, 125V), while everything is off. Now, turn on a large load of ~20A. Note the voltage drop (say it is now 123V, a 2V drop) Now, from ohms law, we know that 2V x 20A or 40W of power is being dissipated as heat somewhere before the volt meter(likely mostly your power cord, but also the marina wiring). Note that number. Run the test every once in a while. If you have a load like a heater or AC that runs everyday, it only requires a glance while it is on. If you note an increase in the voltage drop/Watts of dissipated power, that indicates a problem is developing. It is important to understand it is the drop we are interested in, not the specific voltage. The voltage will fluctuate day/day, and that is fine. The drop for a given load should never change.

You could also see it with an inferred camera, and could/should use one to find the exact location of the problem. But watching the voltage drop will be an early indicator that often you can know just with a glance and not needing to dig anything out an take the time to test.

It would be interesting to run this test before and after a conversion to a Smart Plug. No doubt in my mind, with a larger contact area the voltage drop will be measurably less.

[Dockhead]

Originally Posted by wholybee

Regardless of the type of cordset you have. Something every owner should know how to do. Provided you have accurate volt and amp meters on your boat.

When everything is "good" note the voltage. (Say, 125V), while everything is off. Now, turn on a large load of ~20A. Note the voltage drop (say it is now 123V, a 2V drop) Now, from ohms law, we know that 2V x 20A or 40W of power is being dissipated as heat somewhere before the volt meter(likely mostly your power cord, but also the marina wiring). Note that number. Run the test every once in a while. If you have a load like a heater or AC that runs everyday, it only requires a glance while it is on. If you note an increase in the voltage drop/Watts of dissipated power, that indicates a problem is developing. It is important to understand it is the drop we are interested in, not the specific voltage. The voltage will fluctuate day/day, and that is fine. The drop for a given load should never change.

You could also see it with an inferred camera, and could/should use one to find the exact location of the problem. But watching the voltage drop will be an early indicator that often you can know just with a glance and not needing to dig anything out an take the time to test.

It would be interesting to run this test before and after a conversion to a Smart Plug. No doubt in my mind, with a larger contact area the voltage drop will be measurably less.

You're assuming that all the voltage drop occurs on board. In my experience, that's not usually the case.

[sailingharry]

Originally Posted by Dockhead

You're assuming that all the voltage drop occurs on board. In my experience, that's not usually the case.

He did say that there are several sources, including the marina wire. But the key part of his suggestion, that seems pretty solid, is to monitor for changes. If the toaster pulls a 10V drop most days this year, but suddenly you see 15V, something somewhere changed.


Of course, it's only really useful if you tend to use a repeatable high load device at a single location over a long period. The only time I see a load, other than trickle charging the batteries, is when I'm "out there." A different plug every night. Well..... truth be told, more like "a few nights a month." We rarely tie up, and even then don't usually pay the shore power surcharge.



I think (not 100% sure) that I can get the requisite info right on my Victron Bluetooth app from my inverter. I'm going to start that assessment anyway, even if all I can learn is the variability of marina services. Still be interesting.

[s/v Jedi]

Y’all are just trying new angles to argue more. Smartplug is a pin and sleeve connector plus it has really good locking features and a bit more surface area.

The misinformation in this thread is the whitewashing of the twist & lock 30A connectors which really are the worst of the bunch.

[wholybee]

Originally Posted by Dockhead

You're assuming that all the voltage drop occurs on board. In my experience, that's not usually the case.

No, I am not assuming that. The volt meter should be very near the minimum point of entry on a boat. (plug->breaker->meter) Most places the drop could occur would therefore not be on the boat. If a space heater were plugged into a failing outlet on the boat, for example, that would not show up.

[hughespat57]

Originally Posted by Nepidae

Compared to the 'standard' Marinco boat side receptacle and their cords the SmartPlug is the safest and to date I haven't seen anything else that comes close to the SmartPlug. I'm open if someone has a site reference for a better product.

Any boat to dock electrical setup has to have a 'normal' twist lock end for dockside and it sounded to me like someone was trying to equate the boat side plug of a SmartPlug cord to the shore side which they hadn't seen at any docks, duh.

The SmartPlug is a DIY setup as you remove the boat side receptacle, IF I remember, 2 screws to remove the wiring and 2 screws to remove the receptacle and slide the SmartPlug into the same hole, refasten the 2 screw to hold it in place and reattach the wiring. The wiring is the same so you unscrew it from the old receptacle, inside the boat and reattach the SmartPlug the same way.

The boat side cord plug snaps in, no twisting and the flanges are bigger for better contact. Shore side is the standard twist lock.

IF you got something better, please let me know.

I still stand by my research before pronouncing something wrong with a product, this isn't the 1st time I've seen this, and site references are always helpful.

I did see my post with an actual installation

No doubt Smartplug is better than the 30A twist lock. But “safest” no way anyone can say that yet. Marketing materials are not objective it simply has not been in use long enough to have a proven record.

IEC 309 is an international and UL recognized standard existing for many decades. Pin and sleeve wraps around the pins for contact on both sides almost 3” long. That is twice the surface then the Smartplug which is single sided.

My installation was all used components from ebay. Used and the pins were in perfect condition. It is water proof and they are available for purchases already nickel plated.
I spent less than 250 for two female, two bulkhead and an inline male.

[sstuller]

Originally Posted by hughespat57

I did see my post with an actual installation



No doubt Smartplug is better than the 30A twist lock. But “safest” no way anyone can say that yet. Marketing materials are not objective it simply has not been in use long enough to have a proven record.



IEC 309 is an international and UL recognized standard existing for many decades. Pin and sleeve wraps around the pins for contact on both sides almost 3” long. That is twice the surface then the Smartplug which is single sided.



My installation was all used components from ebay. Used and the pins were in perfect condition. It is water proof and they are available for purchases already nickel plated.

I spent less than 250 for two female, two bulkhead and an inline male.

Can someone explain why shore power cords have twist plugs on both ends but RV cords are twist lock on the RV but a straight plug on the circuit breaker box? So you need two cords that are otherwise identical. I got a 30 amp adapter (twist lock to straight) so I only need one cord. Very few of us are using the boat and the RV at the same time.

[Jammer]

The 30 amp RV connector used in the USA is a special case connector that isn't part of the NEMA standard system. The NEMA equivalent is the 5-30R and 5-30P which do exist and you can order them but I have never seen one in use anywhere.

The RV connector was adopted in the 1940s by trailer parks that served house trailers that were generally not self-contained (The Spartan Royal Mansion was the high end of this type and many are still extant for those interested in googling for some photos and floorplans. Most trailers were of much cheaper construction than the Spartans, with few windows, and have disappeared due to a lack of interest from collectors and restorers). 30 amp 120v service was fairly standard for typical smaller houses prior to the establishment of the Rural Electrification Administration in 1935, which promulgated 60 amp 120/240v split phase service as the residential standard. A connector was necessary and the NEMA standards, though they existed, were not well established at this point in history.

Anyway the trailers had lighting loads and typically an outlet for kitchen appliances. Usually the trailers were either wired for 120v only, or had dual-voltage fixtures that had a 12v lamp and a 120v lamp with separate switches that were part of the same fixture. On dual voltage trailers, fans would have 12v universal motors and have a 120v-to-18v transformer at the fan, with a 3 way switch that would connect the fan to either the transformer or the DC.

Battery charging was at a few amps through a selenium half-wave rectifier.

By the 1950s, 1200 watt water heaters had shown up and were the big load.

At this point, typically the trailer connector was another non-standard non-locking connector, roughly similar to the IEC connector used on computers and data processing equipment but with the phase conductors angled in a crowsfoot shape similar to the New Zealand standard one. Or the cords were hard wired. The trailer connector of the day has fallen into obscurity and is no longer available or used, except on antiques.

I'm a little fuzzy on the history of shore power for boats but I don't think it was widespread until much later, when the standards were more established.