Power Strips and/or extension cords

Okay, take the surge protection out of the equation, let's talk about a simple, non-surge protected power strip with a single pole breaker. Without any surge protection, there is no connection between the two power leads in the power strip and the ground lead, agreed?

 

How does floating neutral vs earth ground provide another set of failure modes? What are these failure modes that don't have anything to do with MOV's? I'm really not aware of any, nor have I experienced any in 43 years on ships.

 

Again, if your device does not have a ground fault, then the fact that the power strip only has a single pole breaker doesn't matter, since a ground fault elsewhere on the ship will not cause the power strip to conduct current and catch fire. Now, if your device does have a ground fault, and in the "unprotected" "neutral" leg, current will flow, and if it reaches the set trip current for that circuit, while there is no breaker on the power strip, it will be protected by the two pole breaker in the ship's circuit, just as if the power strip had a neutral breaker. I disagree with your assertion that a non-surge protected consumer power strip is dangerous, and can cause a fire on a ship, any more than your Iphone charger or a simple plug splitter or extension cord. An extension cord does not have any circuit breaker on either power leg, are these inherently dangerous when used on ships with a floating neutral? Because that is what you are saying, when you say that a non-surge protected power strip is dangerous.

 

And, I have said that the Safety Notice did not stress the fact that it was the combination of the surge protection and the single pole breaker that led to those two fires. However, again, please explain how a single pole breaker, downstream from a double pole breaker, on a power strip with no ground fault, and with devices plugged in that have no ground fault, can cause excessive current and cause a fire.

 

As I've stated, ship provided power strips are usually 220v European power strips, that while they do have a two pole breaker on them, are really preferred because they plug directly into the 220v outlet without a plug adapter, and also provide universal outlets on the strip so that any combination of 220v and 110v plugs can be plugged into the strip. But I have used consumer non-surge protected 110v power strips for decades on ships, and have never had a problem or fire from them. I have had problems and incipient fires from surge protected consumer 110v power strips.

CHENG?

Normally yes, but would you touch a metal-cased power tool lacking an earth lead?

Well, you have all confused me, which isn't that hard. We are on the Veendam in Nov. My husband uses CPAP, I use oxygen and a scooter which needs to be charged. We usually bring a big orange multiple plug plus an extension cord. I do not think the Veendam has been retro-fitted yet. Plenty of plugs on Koningsdam last December. I will call Ship Services and check out Veendam

Well, you have all confused me, which isn't that hard. We are on the Veendam in Nov. My husband uses CPAP, I use oxygen and a scooter which needs to be charged. We usually bring a big orange multiple plug plus an extension cord. I do not think the Veendam has been retro-fitted yet. Plenty of plugs on Koningsdam last December. I will call Ship Services and check out Veendam

Extension cord plus big orange multiple-tap would put a smile on both of us, even if

we need sunglasses ;)

Just no switches (to keep me happy) or pilot lights (to keep CHENG happy?).

I pack a little duct tape in case the extension cord turns out to be a tripping hazard.

CHENG?

 

Normally yes, but would you touch a metal-cased power tool lacking an earth lead?

Who said there is no earth lead? Most (the exception being some older ships) cruise ship, or cargo ship outlets, whether 110v or 220v are three wire (two power leads and a ground), and three prong (even the 220v outlets, if you look carefully, will have two metal prongs on the circumference which are ground pins). People misunderstand the difference between a ground circuit on a ship and a ground circuit on land. Other people misunderstand and think there is no ground on a ship, but there is a very large and effective one, the hull. The only difference is that the "neutral" or "white" lead is not connected to the ground at the circuit breaker box like on land. Think of the 110v (and the shipboard 220v as well) circuit on a ship as being the same as your electric range or water heater. It is connected to the two power leads coming into your house (to provide the 220v), and to the ground lead for safety. Yet, each power lead is not at the ground potential (just like a ship), unlike the 110v wiring in your house. I know that ranges typically also have a neutral wire to provide the 110v for controls, so lets just concentrate on a water heater. Is the water heater unsafe? Nope, because the metal casing is connected to ground, but without a ground fault, there is no connection between the two power leads and ground. Yet, if the water heater goes to ground, it won't shock you because the metal case and the ground wire provide a better path for current than through you to the earth. And, likewise, the circuit breaker is two pole, so any ground fault current will likely trip both power legs.

Almost every power strip I've seen has a three prong plug on it (and that does not imply surge protection). Now, if you want to plug this three prong power strip into an older two prong outlet, with a plug adapter, and decide not to use the screw tab to complete the ground, then you are creating a dangerous situation, but that is a different thing, and not caused by using a power strip with only a single pole breaker on a ship.

Again, the switch on a power strip has nothing to do with the safety of using it on a ship. Pilot lights on power strips have nothing to do with their safety on a ship. The words "surge protected", "joules of protection", "clamping voltage" are the keys to what is unsafe on a ship. If those words are not present on the packaging or the power strip itself (the fine print on the back), then the power strip is safe to use, but it may still be banned from use by cruise line policy.

This confusion over what a non-surge protected power strip is, is why many cruise lines simply ban them altogether, rather than have the port security people trained to detect, or argue about whether the power strip is safe or not.

I would not recommend using a power strip anyway for charging a scooter as well as running a CPAP and oxygen concentrator, all night, unless you checked the amperage rating of the power strip and compared it to the max current draw of all your equipment together, especially the scooter charger.

CHENG?

 

Normally yes, but would you touch a metal-cased power tool lacking an earth lead?

Who said there is no earth lead? Most (the exception being some older ships) cruise ship, or cargo ship outlets, whether 110v or 220v are three wire (two power leads and a ground), and three prong (even the 220v outlets, if you look carefully, will have two metal prongs on the circumference which are ground pins). People misunderstand the difference between a ground circuit on a ship and a ground circuit on land. Other people misunderstand and think there is no ground on a ship, but there is a very large and effective one, the hull. The only difference is that the "neutral" or "white" lead is not connected to the ground at the circuit breaker box like on land. Think of the 110v (and the shipboard 220v as well) circuit on a ship as being the same as your electric range or water heater. It is connected to the two power leads coming into your house (to provide the 220v), and to the ground lead for safety. Yet, each power lead is not at the ground potential (just like a ship), unlike the 110v wiring in your house. I know that ranges typically also have a neutral wire to provide the 110v for controls, so lets just concentrate on a water heater. Is the water heater unsafe? Nope, because the metal casing is connected to ground, but without a ground fault, there is no connection between the two power leads and ground. Yet, if the water heater goes to ground, it won't shock you because the metal case and the ground wire provide a better path for current than through you to the earth. And, likewise, the circuit breaker is two pole, so any ground fault current will likely trip both power legs.

 

Almost every power strip I've seen has a three prong plug on it (and that does not imply surge protection). Now, if you want to plug this three prong power strip into an older two prong outlet, with a plug adapter, and decide not to use the screw tab to complete the ground, then you are creating a dangerous situation, but that is a different thing, and not caused by using a power strip with only a single pole breaker on a ship.

 

Again, the switch on a power strip has nothing to do with the safety of using it on a ship. Pilot lights on power strips have nothing to do with their safety on a ship. The words "surge protected", "joules of protection", "clamping voltage" are the keys to what is unsafe on a ship. If those words are not present on the packaging or the power strip itself (the fine print on the back), then the power strip is safe to use, but it may still be banned from use by cruise line policy.

 

This confusion over what a non-surge protected power strip is, is why many cruise lines simply ban them altogether, rather than have the port security people trained to detect, or argue about whether the power strip is safe or not.

 

I would not recommend using a power strip anyway for charging a scooter as well as running a CPAP and oxygen concentrator, all night, unless you checked the amperage rating of the power strip and compared it to the max current draw of all your equipment together, especially the scooter charger.

My point was that a single point of failure can put line voltage on any metal-cased

power tool which lacks a functioning earth ground.

A similar failure on the neutral leg in a power strip or anything plugged into it would

cause short-circuit current flow from the (floating) neutral to earth. The single-pole

breaker wouldn't protect the power strip, allowing it to ignite before the distribution

panel overcurrent devices reacted.

Let's climb out of the weeds...

Use a power strip or whatever with surge protection afloat? Me: Nope.

Use a power strip with a (single pole) switch while afloat? Me: Nope.

That just about covers all power strips, no?

My point was that a single point of failure can put line voltage on any metal-cased

power tool which lacks a functioning earth ground.

 

A similar failure on the neutral leg in a power strip or anything plugged into it would

cause short-circuit current flow from the (floating) neutral to earth. The single-pole

breaker wouldn't protect the power strip, allowing it to ignite before the distribution

panel overcurrent devices reacted.

 

 

 

Let's climb out of the weeds...

 

Use a power strip or whatever with surge protection afloat? Me: Nope.

Use a power strip with a (single pole) switch while afloat? Me: Nope.

 

That just about covers all power strips, no?

A single point earth fault will allow current to flow from the equipment with the earth fault to ground, just as it does on land. Now any power tool that "lacks a functioning earth ground" is a danger on land or at sea, whether plugged into a power strip or directly into an outlet. I may have misled you when I say that when a single earth fault happens, no current flows on a ship. This is not quite correct, the current will flow from that earth fault to the hull, and then to earth through the sea. The problem with ships is that you have something made with dissimilar metals, and submerged in salt water, a fine electrolyte. So, when earth current flows in the hull, you get galvanic corrosion of the hull or piping, which you don't want. To control any possible current flowing in the hull, the ship has ground sensors that place a very high resistance between the power legs and the hull. An ammeter is placed in this circuit to measure current flow through this circuit (since this provides the connection back to the power system when a ground fault happens, it completes the circuit). When this meter shows current flowing, the engineers will be able to track down the earth fault by isolating one circuit at a time to see if the current flow stops.

My point, and I see that I was not sufficiently clear, is that while current will flow from a single earth fault to ground somewhere on the ship, with a power strip that does not have any connection between the power leads and ground, there will be no current flow from ground into the power strip, so no danger of fire. Only the addition of the MOV semi-conductors between the power leads and ground, provide the possible path for this current from ground to flow back to the power leads from the other earth fault, and complete a circuit through the surge protector, and this completed circuit is what presents the fire hazard. Again, what is the difference between a non-surge protected power strip with a circuit breaker on one leg, and an extension cord with no circuit breaker on any leg?

I apologize for my lack of clarity, this has become second nature to me, and sometimes I gloss over things that I think everyone knows.

Thanks to everyone for the detailed technical information.

Some of the readers are now fully informed and others are completely confused.

 

Back to the original question, what to do?

 

There are two possible answers:

1. Go shopping, spend money for extension cords and power strips that may or may not be allowed by the cruise line. Use up valuable space in your suitcases to carry them to and from the ship, and risk your bags being opened and held for possibly dangerous items.

 

OR

 

2. Spend no extra money, use all your suitcase space for more important items, avoid your bags being opened or delayed, and borrow the necessary cords and power strips (checked and approved by the ship's electricians) from the cruise line at no cost to you.

 

What would an intelligent person do?

Just to clarify. No one ::glances at CHENG?:: has any heartburn with extension

cords. Some have heartburn with some power strips, others with all power strips.

I don't know what ship the OP will be on, but I was just on Eurodam and there were outlets all over the place in verandah room.

What would an intelligent person do?

Just be aware that if one brings a multi plug power strip, one still may have it confiscate.

We were on the Rotterdam in March.

First day was a call at Half moon Cay.

In the late afternoon, the the power in our cabin went out for about thirty seconds, came back on, went back out and again came back on.

When we came back to our cabin late in the evening, the middle third of the cabin (had the desk, TV, loveseat) was without power.

We reported it to Guest Services and went to bed. The power was back on the next morning.

Next day was a sea day. Throughout the day, the power in the middle third of the cabin would go out and come back on. The whole cabin was also blacked out at some points.

Again we reported the problem to Guest Services and I made the statement it was if a circuit breaker was going off and resetting.

I also asked our cabin steward if anyone else was having problems. He said not that he was aware of.

Next day was a port of call. We came back on board ship at lunch time and heard our neighbors next to us return (our cabins were mirror images with their desk area on the other side of the common wall).

Within ten minutes, our power was again going on and off. Called guest services again and once again talked to our cabin steward and suggested that maybe there was a problem with too much being plugged in next door.

He must have talked to his supervisor because he told me later that afternoon that when the cabin next door was turned down for the evening, someone would "look" for the source of the problem

Turns out several multi plug cords had been bought on board by the couple next door and was being used to charge a plethora of electronics.

I was told the cords had been removed by security and we had no further problems.

I should note that the day after the cords were confiscated, a new electrical cable was run from the lobby area, down the hall, and into the electrical box between our cabins. Electrical work was also being done on the cabin that had caused the power problems.

I don't know what ship the OP will be on, but I was just on Eurodam and there were outlets all over the place in verandah room.

When we sailed her in September, I remember there being USB outlets next to the bed. I had to use a CPAP and requested an extension cord but the closest electrical outlet was next to the Verandah door on the shelf where the TV used to sit.

When we sailed her in September, I remember there being USB outlets next to the bed. I had to use a CPAP and requested an extension cord but the closest electrical outlet was next to the Verandah door on the shelf where the TV used to sit.

How did you plug in your CPAP? I put in a request with HAL about this but am concerned that my husband will not be able to use his.

Cheng and Haboob - your posts have been most informative, and they have me thoroughly confused. We are leaving in September on the Grand Asia, and I purchased the Tessan 2 plug, 3 USB power strip. It was advertised as not being a surge protector, but now I wondering . . . Can you tell from the following website if this power strip is safe to use aboard ship? Thanks so much.

https://www.ebay.com/p/Tessan-Portable-2-Outlet-Travel-Power-Strip-With-3-USB-Ports-Charging-Station-5/1383379986

Cheng and Haboob - your posts have been most informative, and they have me thoroughly confused. We are leaving in September on the Grand Asia, and I purchased the Tessan 2 plug, 3 USB power strip. It was advertised as not being a surge protector, but now I wondering . . . Can you tell from the following website if this power strip is safe to use aboard ship? Thanks so much.

https://www.ebay.com/p/Tessan-Portable-2-Outlet-Travel-Power-Strip-With-3-USB-Ports-Charging-Station-5/1383379986

I certainly could not tell from the ebay site, so I went to Tessan's site. Their site is not very tech oriented, but it does not make any mention of surge protection, but I have found that even manufacturer's websites can contain misleading or incorrect information. Your best bet is to contact Tessan directly at "support@tessan.com" and ask if it is surge protected. Make sure they answer in terms of "surge protection" and not "over voltage protection". You can also check on the fine print on the back of the device or in the paperwork that everyone throws out, whether it has terms like "joules" or "clamping voltage", as these are keys to surge protection. I just looked at the "exploded" view of the internals of this device, and I don't see the telltale shape of the MOV's used in surge protection, so my confidence that it is not is strengthened, but I still recommend contacting them.

I have found that most combination power strip/USB hubs are surge protected, though some aren't. To save confusion, I recommend a multi-USB hub (these typically have a two prong plug, which precludes surge protection), and a simple $5 power strip from Home Depot, or an outlet splitter. If you go the separate USB hub route, with a plug adapter, this can be plugged into the 220v outlet, leaving the 110v outlet free for hair care appliances, while your combination device you list could only be plugged into the 110v outlet to get 110v out of the power outlets.

I certainly could not tell from the ebay site, so I went to Tessan's site. Their site is not very tech oriented, but it does not make any mention of surge protection, but I have found that even manufacturer's websites can contain misleading or incorrect information. Your best bet is to contact Tessan directly at "support@tessan.com" and ask if it is surge protected. Make sure they answer in terms of "surge protection" and not "over voltage protection". You can also check on the fine print on the back of the device or in the paperwork that everyone throws out, whether it has terms like "joules" or "clamping voltage", as these are keys to surge protection. I just looked at the "exploded" view of the internals of this device, and I don't see the telltale shape of the MOV's used in surge protection, so my confidence that it is not is strengthened, but I still recommend contacting them.

 

I have found that most combination power strip/USB hubs are surge protected, though some aren't. To save confusion, I recommend a multi-USB hub (these typically have a two prong plug, which precludes surge protection), and a simple $5 power strip from Home Depot, or an outlet splitter. If you go the separate USB hub route, with a plug adapter, this can be plugged into the 220v outlet, leaving the 110v outlet free for hair care appliances, while your combination device you list could only be plugged into the 110v outlet to get 110v out of the power outlets.

Thank you, Cheng, for taking the time to check this out. I will follow your advice and call Tessan. Their website is less than helpful. Actually, I bought it through Amazon, and they give considerable detail. I will check for "clamping voltage". I did not see "joules", however.

Thank you, Cheng, for taking the time to check this out. I will follow your advice and call Tessan. Their website is less than helpful. Actually, I bought it through Amazon, and they give considerable detail. I will check for "clamping voltage". I did not see "joules", however.

Unfortunately, I have found that not all the information given on Amazon is correct. Found one power strip that claimed to be "safe for cruise ships", and when I went to the manufacturer's site, it clearly stated it was surge protected.

Many people have complained about the lack of outlets in the cabins. Usually there is only one sometimes two. I was told no power strips allowed when we travel on the Amsterdam last summer We rented a refrigerator for 2.00 a day and with that they give you an extension cord that has extra outlets that can be used. Problem solved.

Unfortunately, I have found that not all the information given on Amazon is correct. Found one power strip that claimed to be "safe for cruise ships", and when I went to the manufacturer's site, it clearly stated it was surge protected.

I submitted a request to Tessan. We will see what they say. Amazon did give links to the manufacturer's info, but . . . Will let you know if this device is actually not surge protected. To be on the safe side, I will bring along an extension cord (2 prong!)

Cheng,

Thought you would be interested in Tessan's response to my question re the power strip (very quick response, by the way).

Dear Virginia,Thank you contact us, please don't worry. This power strip is not a surge protector, it can work on the cruise. Many customers also use it on the cruiseThat is not correct, many power strip without a power surge are the 3-prong plug. Our plug is the 3-prong plug.Any question please don't hesitate to contact us Best WishTESSAN

I think I will ship it along with our luggage in September - along with an extension cord!

That is not correct, many power strip without a power surge are the 3-prong plug.

This message may have been drafted using voice recognition. Please forgive any typos.

I think there is some general confusion about surge protection and the number of prongs in the plug. Harken back to high school when you learned about logical implications... All surge protected power strips have three prongs. That does NOT mean that all three prong power strips are surge protected.

 

 

 

This message may have been drafted using voice recognition. Please forgive any typos.

You missed the beginning of the discussion where Cheng made the two v. three prong comments. So your "harken back to high school" comment was out of place.

I've read every post, and I'm sure that Cheng didn't say that all three prong power strips have surge protection.

You missed the beginning of the discussion where Cheng made the two v. three prong comments. So your "harken back to high school" comment was out of place.

This message may have been drafted using voice recognition. Please forgive any typos.

Cheng,

 

Thought you would be interested in Tessan's response to my question re the power strip (very quick response, by the way).

 

Dear Virginia,Thank you contact us, please don't worry. This power strip is not a surge protector, it can work on the cruise. Many customers also use it on the cruiseThat is not correct, many power strip without a power surge are the 3-prong plug. Our plug is the 3-prong plug.Any question please don't hesitate to contact us Best WishTESSAN

I think I will ship it along with our luggage in September - along with an extension cord!

Trying to decipher your questions from their answers, I believe you misunderstood some of my comments. I said that a device with a two prong plug cannot be surge protected, but the converse of this is not always true, a device with a three prong plug may or may not be surge protected. I.e. the presence of a third prong does not guarantee surge protection. I would recommend a three prong power strip for anyone, anywhere.

Trying to decipher your questions from their answers, I believe you misunderstood some of my comments. I said that a device with a two prong plug cannot be surge protected, but the converse of this is not always true, a device with a three prong plug may or may not be surge protected. I.e. the presence of a third prong does not guarantee surge protection. I would recommend a three prong power strip for anyone, anywhere.

However I may have inartfully worded my question to Tessan, I did understand your comments to me. I so appreciated your assistance. Thank you.