Combine 3 x single phase/220v = 3-phase power?

[JumbleDuck]

I can't understand why it's still going on!

Mainly because people who haven't read the thread - or in one case haven't even read the first post - keep popping up to do their Corporal Jones acts.

 

[Alex_Blackwood]

And your authority for saying this is ... ?

Experience!

 

[PaulRainbow]

I'm really impressed with the interest in this thread - thanks to everyone for contributing so actively (be nice to each other now though!). Through arguments and counter arguments I have learned even more.

Perhaps I can help summarize in case it has become difficult to get an overview of the many posts:

1) Safety: Any change in installations will be carried out by a licensed electrician. No DIY. This thread is purely for my own education so that I can have a reasonably educated conversation with the electrician, which I'm sure the electrician will appreciate as it will make his job easier.
2) Generator: I confirm I have a 3-phase generator onboard, I can't recall the capacity but it can pull all the boat's systems.
3) Existing wiring: I have one 3-phase shore power supply. Onboard, it splits into 3 single-phase groups that power my 240v systems onboard which include everything from domestic appliances to pumps etc. It also supplies one 3-phase supply to my grey water pump.
4) Shore power supply: I expect to be able to access a single 3-phase shore power supply, or 3 or more single-phase (16a) supplies.
5) My objective: I want to be able to power all the boat's systems regardless of the type of shore power supply I may meet at a marina.
6) My conclusion: The simplest solution is to add 3 single-phase shore power connections that each and separately power each of my 3 onboard groups. For my 3-phase pump I will add a phase converter to the onboard single phase group that runs my pumps that I can temporarily shut off so that the group's full capacity is available for the phase converter. I will try the converter mentioned in post #44 that ramps up the hz so that starting the pump doesn't trip the fuse. If that doesn't work I'll just run the pump off the generator which is however not my preferred solution because it is super noisy. I have noted the suggestions to change the pump but I do not want to do that at this stage. When I say "I" in this part, what I actually mean is that I will have these suggestions in mind as I discuss options with the electrician, but it will be the electrician who will decide on the best and safest option.

I hope this covers any open ends of this thread, if not then please let me know and I'm happy to clarify - it's the least I can do when you all have put so much energy into educating me!

Thanks for posting this, it looks like you have a good understanding of everything. It would be interesting to hear what your electrician comes up with.

 

[pawl]

So, no real knowledge of marine systems ? If you follow the link in post #114 (also noting post #116, you will see that the system i suggest is common place. Some of the posters in the mobo thread own modern multi £million boats, wired exactly as i described.

#117 references the commercial regs for three phase (although they don't directly apply to marine installations) and the ISO that has to be followed with new build boats, both allow such installations.

Boats are unlike domestic or commercial installations. They have a mix of AC and DC and a variety of data systems. Power, on a single boat, can consist of 12v DC, 24v DC, 240v A, 3 phase AC and can be supplied by shore power, generator and/or inverter. It can have several battery banks and several charging systems. I design and install these systems for a living. The suggested installation is very simple, a few contactors and a changeover switch will keep all circuits separate and some RCDs and MCBs will provide more than adequate safety measures. The system is simple, easy to instal, relatively inexpensive and 100% safe, it also complies with all current legistlation, although it sin't required to do so.

Given that this is my day job and i've posted overwhelming evidence to support my suggested installation, it's very disappointing that you and one or two others are still arguing that i'm wrong.

Firstly, I think that it is completely out of order to accuse people of not knowing what they are talking about just because they disagree with your views.

As I understand it, the OP wants to be able to run his 3 ph pump while berthed without a 3 ph supply. He does not want to alter his pump arrangements nor does he want to run his generator whilst alongside. Quite right, if you’ve ever berthed overnight on the same pontoon as a working fishing boat you will know how annoying their generators can be.

As he obviously already knows, he can do this quite simply by using the “phase splitter” which he has provided a link to. This device, which I would call a digital inverter, will do the job but can only supply at the input voltage. However, he has a dual voltage motor, so he could use the lower voltage configuration by changing the connections from “star” (if that is what it is now), to “delta”. He could use a changeover switch to do this. If he wanted to run the motor at 415 v he could use an analogue “phase converter”.

So far so good, the problem is that imho, given the motor size, he won’t be able to run either of these devices from a 16 amp supply, again I think that he already knows this. If he was to follow the suggestions of using several 16 amp supplies he would have to connect them together in order to get to the required amps to run the inverter. Now I’m not suggesting that he does this, but that seems to me to be the question he is asking.

32 amp supplies are quite common in marinas, I’ve sometimes been put on berths that only have 32 amp sockets, in fact I carry an adapter lead with me so that I can plug in. Imho it would be simpler to have a lead made up where the plug is a 32 amp 1 ph and the trailing socket is suited to his 3ph five pin inlet (assuming that is what he has) and simply jump the 240v supply from one line sleeve to the other two. This could be done inside the trailing socket and probably, no alteration to the boat would be needed. However, this needs to be looked into as we don’t know enough about the actual wiring scheme on board.

If he didn’t run the washer, dryer or an electric kettle at the same time as using the pump I expect he would be able to run the inverter. I don’t think he’s said how he heats his water so we don’t know if that’s going to be a problem or not. The generator doesn’t come into it as, if it’s hard wired into the system, it should be locked off, or certainly isolated from, shore power.

My views on the use of several different shore power supplies was meant more generally and was not intended for or directed at, the OP. This may not have been very clear from my post, sorry. I’m just trying to point out that there is a risk, however slight, of picking up different phases of the marina’s 3 phase supply. Perhaps ok if the supplies are kept entirely separate on board but in the real world things go wrong, faults occur, wiring can be incorrectly installed etc. etc.

I don’t accept the argument that if something’s been done for ages it’s ok to carry on doing it. Some people like to jump off cliffs into the water below, but that doesn’t mean that I should also do it, because, you know what, sometimes they get killed. If you inadvertently bring two separate phase supplies onto your boat you have the potential of over 400 volts between the phases, if you’ve ever seen a phase to phase short you will know that it can be spectacular. Even assuming that the supply trips out there can be a sizeable flash which if you’re holding the item could cause injury and would certainly be enough to start a fire.

These are just my personal views and I don’t suggest that anyone should act on them. I’m quite happy to be challenged on any points by sensible argument. I was once acquainted with a chap who got electrocuted whilst working in a house, not even 3 phase, something he was competent to do, things do go wrong. I think that this brought home to me at least, that electrical safety not some theoretical concern but real life or in this case death.

 

[PaulRainbow]

Firstly, I think that it is completely out of order to accuse people of not knowing what they are talking about just because they disagree with your views.

As I understand it, the OP wants to be able to run his 3 ph pump while berthed without a 3 ph supply. He does not want to alter his pump arrangements nor does he want to run his generator whilst alongside. Quite right, if you’ve ever berthed overnight on the same pontoon as a working fishing boat you will know how annoying their generators can be.

As he obviously already knows, he can do this quite simply by using the “phase splitter” which he has provided a link to. This device, which I would call a digital inverter, will do the job but can only supply at the input voltage. However, he has a dual voltage motor, so he could use the lower voltage configuration by changing the connections from “star” (if that is what it is now), to “delta”. He could use a changeover switch to do this. If he wanted to run the motor at 415 v he could use an analogue “phase converter”.

So far so good, the problem is that imho, given the motor size, he won’t be able to run either of these devices from a 16 amp supply, again I think that he already knows this. If he was to follow the suggestions of using several 16 amp supplies he would have to connect them together in order to get to the required amps to run the inverter. Now I’m not suggesting that he does this, but that seems to me to be the question he is asking.

32 amp supplies are quite common in marinas, I’ve sometimes been put on berths that only have 32 amp sockets, in fact I carry an adapter lead with me so that I can plug in. Imho it would be simpler to have a lead made up where the plug is a 32 amp 1 ph and the trailing socket is suited to his 3ph five pin inlet (assuming that is what he has) and simply jump the 240v supply from one line sleeve to the other two. This could be done inside the trailing socket and probably, no alteration to the boat would be needed. However, this needs to be looked into as we don’t know enough about the actual wiring scheme on board.

If he didn’t run the washer, dryer or an electric kettle at the same time as using the pump I expect he would be able to run the inverter. I don’t think he’s said how he heats his water so we don’t know if that’s going to be a problem or not. The generator doesn’t come into it as, if it’s hard wired into the system, it should be locked off, or certainly isolated from, shore power.

My views on the use of several different shore power supplies was meant more generally and was not intended for or directed at, the OP. This may not have been very clear from my post, sorry. I’m just trying to point out that there is a risk, however slight, of picking up different phases of the marina’s 3 phase supply. Perhaps ok if the supplies are kept entirely separate on board but in the real world things go wrong, faults occur, wiring can be incorrectly installed etc. etc.

I don’t accept the argument that if something’s been done for ages it’s ok to carry on doing it. Some people like to jump off cliffs into the water below, but that doesn’t mean that I should also do it, because, you know what, sometimes they get killed. If you inadvertently bring two separate phase supplies onto your boat you have the potential of over 400 volts between the phases, if you’ve ever seen a phase to phase short you will know that it can be spectacular. Even assuming that the supply trips out there can be a sizeable flash which if you’re holding the item could cause injury and would certainly be enough to start a fire.

These are just my personal views and I don’t suggest that anyone should act on them. I’m quite happy to be challenged on any points by sensible argument. I was once acquainted with a chap who got electrocuted whilst working in a house, not even 3 phase, something he was competent to do, things do go wrong. I think that this brought home to me at least, that electrical safety not some theoretical concern but real life or in this case death.

There are already tried, tested and approved ways of doing what the OP wants and i've repeatedly posted what they are, including extracts of the current regs an ISO. There is no need to try to invent alternative ways of doing it, if any of the risks you describe above were a concern the legislation would not permit them.

You will see in post #120 that the OP has understood the situation and will now consult a qualified electrician, so my "work" here is done.

 

[pawl]

There are already tried, tested and approved ways of doing what the OP wants and i've repeatedly posted what they are, including extracts of the current regs an ISO. There is no need to try to invent alternative ways of doing it, if any of the risks you describe above were a concern the legislation would not permit them.

You will see in post #120 that the OP has understood the situation and will now consult a qualified electrician, so my "work" here is done.

I would draw your attention to the IEE Wiring Regulations fig 709.3 in the 17th Edition (the last one that I have). In particular item (iii).

"For safety reasons, your craft must not be connected to any other socket outlet than that allocated to you and the internal wiring on your craft must comply with the appropriate standards."

 

[PaulRainbow]

I would draw your attention to the IEE Wiring Regulations fig 709.3 in the 17th Edition (the last one that I have). In particular item (iii).

"For safety reasons, your craft must not be connected to any other socket outlet than that allocated to you and the internal wiring on your craft must comply with the appropriate standards."

IEE Wiring Regulations do not apply to boats. Now would be a good time to stop digging.

 

[SteveA]

So, no real knowledge of marine systems ? If you follow the link in post #114 (also noting post #116, you will see that the system i suggest is common place. Some of the posters in the mobo thread own modern multi £million boats, wired exactly as i described.

#117 references the commercial regs for three phase (although they don't directly apply to marine installations) and the ISO that has to be followed with new build boats, both allow such installations.

Boats are unlike domestic or commercial installations. They have a mix of AC and DC and a variety of data systems. Power, on a single boat, can consist of 12v DC, 24v DC, 240v A, 3 phase AC and can be supplied by shore power, generator and/or inverter. It can have several battery banks and several charging systems. I design and install these systems for a living. The suggested installation is very simple, a few contactors and a changeover switch will keep all circuits separate and some RCDs and MCBs will provide more than adequate safety measures. The system is simple, easy to instal, relatively inexpensive and 100% safe, it also complies with all current legistlation, although it sin't required to do so.

Given that this is my day job and i've posted overwhelming evidence to support my suggested installation, it's very disappointing that you and one or two others are still arguing that i'm wrong.

Paul I'm surprised that you have time for your day job AND have the patience to continue with this thread; Oh by the way you forgot about power can also be 500v DC and 3.3Kv 3 phase A/C.

 

[PaulRainbow]

Paul I'm surprised that you have time for your day job AND have the patience to continue with this thread

Time wise, it's probably better than watching soaps on the TV Steve, although it does get a bit East Enders on here at times

Patience is another subject, it's very frustrating with some of these threads, i do sometimes question why i'm here.

Oh by the way you forgot about power can also be 500v DC and 3.3Kv 3 phase A/C.

Yet to work on a boat with either of those. My point was, 12 VDC, 24 VDC, 240 AC and three phase can exist on one boat. Three phase isn't common on small leisure craft (more common on larger commercial vessels, which the OPs used to be), but most of the bigger mobos have 12 VDC, 24 VDC and 240 AC.

 

[septiclecky]

Even if you get a single phase to three phase convertor the output of the convertor would depend upon what the supply amperage, which I would suspect not be large enough over the three phases to supply your equipment onboard.

Plugging into different sockets on the berth may cause other problem as it depends on how the sockets are connected along the multiple berths.

 

[PaulRainbow]

Plugging into different sockets on the berth may cause other problem as it depends on how the sockets are connected along the multiple berths.

Such as ?

 

[TernVI]

There are already tried, tested and approved ways of doing what the OP wants and i've repeatedly posted what they are, including extracts of the current regs an ISO. There is no need to try to invent alternative ways of doing it, if any of the risks you describe above were a concern the legislation would not permit them.

You will see in post #120 that the OP has understood the situation and will now consult a qualified electrician, so my "work" here is done.

What ISO standard are you referring to?
It's worth bearing in mind that the standards for floating caravans yachts are somewhat diverse from commercial vessels.
An electrician qualified in one field may not be familiar with 'ship' practice, and a commercial vessel converted to 'leisure' or 'domestic' use could be an interesting mix of standards. Never mind the 3 phases, there is quite likely a whole world of pain arguing about 'earth' awaiting the OP.

 

[PaulRainbow]

What ISO standard are you referring to?
It's worth bearing in mind that the standards for floating caravans yachts are somewhat diverse from commercial vessels.
An electrician qualified in one field may not be familiar with 'ship' practice, and a commercial vessel converted to 'leisure' or 'domestic' use could be an interesting mix of standards. Never mind the 3 phases, there is quite likely a whole world of pain arguing about 'earth' awaiting the OP.

I refer to the ISO that would be applicable to the OPs vessel, were it a new build. As it's not a new build it actually isn't subject to any ISO.

There is no "interesting mix" of standards caused by the vessel being an ex fishing vessel and now a leisure vessel.