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Post by phoenix on Sept 13, 2017 19:17:55 GMT
How old is the transformer? I assume you bought it as a consumer and it was not a Co purchase? UK purchase or delivered to France? You could have a case under the consumer acts if it is less than 6 years old. Which means you could get a hefty discount off a new one.about about 7-8 years so unlikely
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Post by phoenix on Sept 13, 2017 19:22:52 GMT
I'm a bit wary of advising on matters like this for liability reasons. OK understood just looking for views on what I proposed and alternatives ideas - for which many thanks
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Post by Graham on Sept 13, 2017 20:37:37 GMT
How old is the transformer? I assume you bought it as a consumer and it was not a Co purchase? UK purchase or delivered to France? You could have a case under the consumer acts if it is less than 6 years old. Which means you could get a hefty discount off a new one.about about 7-8 years so unlikely Worthwhile asking them the Transformers should should last almost infinite. BTW you said you were in France yes/no? What is the voltage? UK is 230V nominal mind is saying France to 220V, now what effect dos that have on the startup current? Mind is not working. Just thinking that could be the reason for the failure maybe not.
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Post by smileypete on Sept 13, 2017 20:59:03 GMT
One could argue that leaving a boat based isolation transformer unattended for long periods is a bit risky, the shoreline could rub through and make the hull live unless there's an RCD on the shore side. Maybe use a shoreline made from braided cable? (type SY): www.tlc-direct.co.uk/Products/MF2dot5slash3.html but wouldnt that earth the hull to the shoreSans IT, maybe run the frost protection heaters off an extension lead with a passive (latching) RCD at the shore end of the lead, something like this: www.screwfix.com/p/bg-13a-switched-weatherproof-rcd-fcu/20523 might be a lot simpler/cheaper but wouldnt that leave the hull unearthed with respect to the supply which everyone says is a no no and would it work Ok with Belgian floating live and neutral/
Then when back on the boat just use a decent GI with LED status monitor on a normal shoreline inlet. A simple electric heater for frost protection shouldn't mind floating earth and neutral, after all they must be used in belgian dwellings with a similar supply setup. A boat based IT still leaves the hull unearthed with respect to the shore supply, so you're entirely reliant on any upstream RCD (if fitted!) for protection from the shoreline cable possibly shorting to a metal hull or other metalwork. Though truth be told I doubt hardly any UK marina/mooring supplies don't have RCDs these days, dunno about the continent. >>>IF<<< there's no RCD on the pontoon socket (ie with a test button) and the IT is based on the boat, and the shoreline cable is at any risk of abrasion and contact with metal hull etc, then it'd probably be a wise idea to add an RCD at the shore end of the hookup cable somehow, and/or use extra cable protection or abrasion resistant cable. Trouble with ITs is the poor people advised to fit one get a bit baffled by the IT/GI arguments, some of which are bullshit frankly, and so don't fully get the implications of having an IT on the boat.
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Post by phoenix on Sept 18, 2017 6:36:06 GMT
One could argue that leaving a boat based isolation transformer unattended for long periods is a bit risky, the shoreline could rub through and make the hull live unless there's an RCD on the shore side. Maybe use a shoreline made from braided cable? (type SY): www.tlc-direct.co.uk/Products/MF2dot5slash3.htmlSans IT, maybe run the frost protection heaters off an extension lead with a passive (latching) RCD at the shore end of the lead, something like this: www.screwfix.com/p/bg-13a-switched-weatherproof-rcd-fcu/20523Then when back on the boat just use a decent GI with LED status monitor on a normal shoreline inlet. I have been thinking about all that has been said, the IT does have its downside, cost, weight, ineffciency, fire risk if a fault develops whist unattended??? The issue I had with GIs is the Belgium non neutral earthed system and would it be OK to use with my English wiring on the boat, but I guess they buy the same household equipment as we do and all seems to work, the only difference is that it would be desirable to upgrade my 2 mcbs to double pole. However (still unprotecteed by either GI or IT,) we plugged in last night at a transit mooring which turned out to have the floating neutral and the Victron multiplus did not like it at all, wouldnt let any electric through to the sockets. Any idea what is going on here and solution? I quote below from Mr Google how the Belgium system works, not strictly floating but both live and neutral 100 volts plus different to earth; "In Belgium we have an old electrical network. In residential areas we only get 230V phase to phase. Three-phased power is delivevered to every house on only three wires, without a fourth neutral wire (cheap ass-electricity company). So if we measure any conductor, there is a tension of about 133V relative to ground. There is no "live" and "neutral" wire to the plugs in my room, both are ~133V, and because of the phase angle difference I can get 230V between the two.
Most electrical cables still have blue and brown conductors but both of them shoud be considered live. All the breakers in my home do open both phases. Earthed electrical plugs are keyed by the earth connector but I don't know of any product that assumes it will get the "live" on one plug and the "neutral" on the other."
Edit have rechecked connections, the Belgium socket is normal live and neutral just 1.5 volts ac between neutral and earth so not floating as i thought, the problem is that they have transposed the live and neutral, now when I connect appliances direct to the incomng no problems, but when I connect via the Victron rcds upstream and downstream trip, why is this? All works fine after swopping wires! Still need to know what the Vicron will think of the floating live and negative at the home mooring. Thanks
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Post by Deleted on Sept 18, 2017 7:01:04 GMT
What you are seeing is Delta power there is no neutral Its a 3 phase supply with 230v between phases. This means you should use double pole MCB. Also most RCBO/RCD only disconnect one pole so you would need to select those very carefully, choosing one that is truly DP. Simplest way is to stay with an IT. As for victron from memory they will detect if the "neutral" is above 0v and behave as described, I believe it can be overridden in settings. We have just built two distribution systems that switch between delta and star supplies its a PITA and expensive
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Post by Telemachus on Sept 18, 2017 7:05:54 GMT
We have a Travelpower as one of the two possible sources of mains power to the Combi, the other being the shore power socket. The Travelpower is a centre-tapped device, ie no live or neutral, the two conductors are at ~110v. Same idea as the Belgian system. It doesn't cause any problem with the Combi. However we do have double pole breakers. Most breakers are double pole, are you sure yours aren't?
Our Combi is a Mastervolt which seems fairly tolerant of most things, but Victrons have a setting for tolerating "nasty" mains, maybe you should try that. Combis also have limits for max and min incoming voltage. Did you check to see what the voltage was?
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Post by JohnV on Sept 18, 2017 7:17:51 GMT
Like Nick I have not come across RCD's or RCBO's that only switch the phase and not the neutral. All the ones I know about are quite happy with any type of earth system as they are purely looking at the current flows in each wire and measuring the difference. .... MCB's .... different animal
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Post by phoenix on Sept 18, 2017 7:34:44 GMT
Thanks for the replies which I only saw after editing post doh.
Useful info now thinking what to do next.
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Post by Deleted on Sept 18, 2017 8:04:18 GMT
Like Nick I have not come across RCD's or RCBO's that only switch the phase and not the neutral. All the ones I know about are quite happy with any type of earth system as they are purely looking at the current flows in each wire and measuring the difference. .... MCB's .... different animal How many would you like me to show you? All single module RCBO with the exception of the one we manufacture only disconnect the live. There are some double module ones that don't disconnect the neutral as well, not many I grant you but they do exist. I have to assume Nick didn't mean MCB when he said most are double pole!
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Post by Telemachus on Sept 18, 2017 8:56:32 GMT
Like Nick I have not come across RCD's or RCBO's that only switch the phase and not the neutral. All the ones I know about are quite happy with any type of earth system as they are purely looking at the current flows in each wire and measuring the difference. .... MCB's .... different animal How many would you like me to show you? All single module RCBO with the exception of the one we manufacture only disconnect the live. There are some double module ones that don't disconnect the neutral as well, not many I grant you but they do exist. I have to assume Nick didn't mean MCB when he said most are double pole! I wasn't clear but yes, I mean RCDs and RCBOs. Anyway, this has made me think about it properly! BS EN ISO 13297 (small craft AC systems) says that when using an unpolarised power source (ie neutral not at the same potential as earth), overcurrent protectors must interrupt both conductors. We have an RCBO which does this but as Loddon implies, if you have separate RCD and MCB, the MCBs typically don't interrupt the "neutral" conductor. just thinking about the implications of this, if there is a dead short from either conductor to earth, I think the RCD would trip. If there is a short between "neutral" and earth, I don't think an MCB would trip as it's checking current in the live conductor. But so long as the RCD does, is there a hazard? I can't immediately see it. Where there is perhaps a hazard is that if you trip the MCB so as to isolate the circuit, you will still have 110v on the neutral conductor. But how much does that matter? Anyway, best practice is to comply with the ISO.
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Post by JohnV on Sept 18, 2017 9:47:39 GMT
Like Nick I have not come across RCD's or RCBO's that only switch the phase and not the neutral. All the ones I know about are quite happy with any type of earth system as they are purely looking at the current flows in each wire and measuring the difference. .... MCB's .... different animal How many would you like me to show you? All single module RCBO with the exception of the one we manufacture only disconnect the live. There are some double module ones that don't disconnect the neutral as well, not many I grant you but they do exist. I have to assume Nick didn't mean MCB when he said most are double pole! My apologies ..... I just went into my stores and actually examined them properly MEM, Merlin and Crabtree single modules...... SP. Merlin, Doepke, MEM, Crabtree and Ashley two modules....... DP. ASS out of U and Me syndrome ...... I should have known better ...... (all mine are left over from shore side domestic jobs years ago used double module on Sabina .... single modules weren't around that long ago !!!)
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Post by Deleted on Sept 18, 2017 11:36:46 GMT
How many would you like me to show you? All single module RCBO with the exception of the one we manufacture only disconnect the live. There are some double module ones that don't disconnect the neutral as well, not many I grant you but they do exist. I have to assume Nick didn't mean MCB when he said most are double pole! My apologies ..... I just went into my stores and actually examined them properly MEM, Merlin and Crabtree single modules...... SP. Merlin, Doepke, MEM, Crabtree and Ashley two modules....... DP. ASS out of U and Me syndrome ...... I should have known better ...... (all mine are left over from shore side domestic jobs years ago used double module on Sabina .... single modules weren't around that long ago !!!) No bother its somthing I am very aware of because the company I work for manufactures their own. We also use single module DP mcb when the need arises and that is what I have on the boat, means the consumer unit can be half the size.
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Post by phoenix on Sept 23, 2017 11:03:11 GMT
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Post by Graham on Sept 23, 2017 15:00:17 GMT
So it is a non-neutral earth floating supply and only 50V between the two lives and the incoming earth I assume the measurements were done to the incoming earth. That suggests to me a GI would be passing current. Be interested to know what the measurements were to a spike in the bank.
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