10 years ago, the 240V system on the OKA was given a full certificate of approval by a qualified electrician who specialised in RVs. It comprised some power points fed by a PSW inverter and protected by a dedicated RCD.
This would be similar to virtually all RVs whenever the input is plugged into a generator or inverter. It is an "isolated" system.
Well, after 10 years of constant use, I recently discovered that the RCD was in fact totally useless, despite tripping when pressing the test button.
I now have an RVD-EI (Residual Voltage Detection Unit) installed and am now getting the protection I always thought we had. Thanks to Ian (Powerstream) for his service and advise. http://www.safelec.com.au
10 years ago, the 240V system on the OKA was given a full certificate of approval by a qualified electrician who specialised in RVs. It comprised some power points fed by a PSW inverter and protected by a dedicated RCD.
This would be similar to virtually all RVs whenever the input is plugged into a generator or inverter. It is an "isolated" system.
Well, after 10 years of constant use, I recently discovered that the RCD was in fact totally useless, despite tripping when pressing the test button.
I now have an RVD-EI (Residual Voltage Detection Unit) installed and am now getting the protection I always thought we had. Thanks to Ian (Powerstream) for his service and advise. http://www.safelec.com.au
Cheers, Peter
Not knowing what you don't know can be a real problem Peter....
10 years ago, the 240V system on the OKA was given a full certificate of approval by a qualified electrician who specialised in RVs. It comprised some power points fed by a PSW inverter and protected by a dedicated RCD.
This would be similar to virtually all RVs whenever the input is plugged into a generator or inverter. It is an "isolated" system.
Well, after 10 years of constant use, I recently discovered that the RCD was in fact totally useless, despite tripping when pressing the test button.
I now have an RVD-EI (Residual Voltage Detection Unit) installed and am now getting the protection I always thought we had. Thanks to Ian (Powerstream) for his service and advise. http://www.safelec.com.au
Cheers, Peter
HI Peter
A good lesson for ALL
If you use a generator or inverter, even if permanently wired, have ALL the power outlets checked with a RCD tester to confirm you have the protection you think you have
Do not just get one outlet tested
Do not think because the RCD trips when the" test" button is pressed, that ALL is OK
The 'test button only confirms that the RCD mechanism is operating
It does not confirm that wiring is ok /correct for the RCD to give protection
Then, IF there is a problem I would strongly suggest you get a " Safelec RVD" fitted
Something that I hope many will take notice of :)
I have been trying to get the message through for a loooong time
PeterQ
--
-- Edited by oldtrack123 on Sunday 21st of December 2014 11:28:06 PM
I am relatively new in the RV world, and bow to the wisdom of the great experienced campers in this forum who have taught me so much in such a short time. However, I do have a lifetime of experience in the electrical field which may not necessarily apply to vans, etc. My thoughts on RCDs in vans and MHs are just this. An RCD - in my day they were ELCBs (earth leakage circuit breakers) which detected a small imbalance between the current flowing to the appliance, etc. through the active conductor and the current flowing back to the source through the neutral conductor. The assumption was that a person may be providing a secondary path by contact with the active and earth (e.g. sticking a fork into the toaster with one hand while you are standing barefooted on the wet grass outside the van) - in other words, being electrocuted. This type of protection is possible only where the neutral and earth connections are at the same potential, i.e. connected together at the switchboard and the power station. In a situation where you have an inverter or genny supply, if you don't connect these to earth you cannot receive a shock unless you actually touch both the active and neutral conductors at the same time (and that's not easy to do) as the supply is now isolated from earth. I have wired my inverter circuit GPOs without an earth (active and neutral only). I welcome any comments from anyone who may be able to correct me if I'm mistaken as to the wiring rules of RCD devices on inverter and genny circuits in van environments . I would also think that the SAA rules would regard the entire van as an appliance, since it is connected by a removable lead and not hard wired. Therefore it could be connected as an earthed - or a double insulated - appliance which requires no earth connection.
-- Edited by Stratman77 on Monday 22nd of December 2014 02:58:32 AM
__________________
Best regards,
Chris
Licensed Electrician, Electronics, Gaming & Computer Technician. Now retired and loving it!
I just watched the "how a RCD works" in Peter n Margrets link.
How many people are out there using generators, totally unaware they're not protected.
My previous post (back a page) 240 volt protection, was because my 1999 van has no protection device fitted. I am happy this topic has been raised again.
The thing now is to find an electrician who is knowledgeable enough to fit the correct protection device.
I use an inverter (not wired into the van) to charge laptop, run a box fan & bug zapper. I'm assuming I have no protection when using the inverter?????
I am relatively new in the RV world, and bow to the wisdom of the great experienced campers in this forum who have taught me so much in such a short time. However, I do have a lifetime of experience in the electrical field which may not necessarily apply to vans, etc.
[1]
My thoughts on RCDs in vans and MHs are just this. An RCD - in my day they were ELCBs (earth leakage circuit breakers) which detected a small imbalance between the current flowing to the appliance, etc. through the active conductor and the current flowing back to the source through the neutral conductor.
[2]
The assumption was that a person may be providing a secondary path by contact with the active and earth (e.g. sticking a fork into the toaster with one hand while you are standing barefooted on the wet grass outside the van) - in other words, being electrocuted.
[3]
This type of protection is possible only where the neutral and earth connections are at the same potential, i.e. connected together at the switchboard and the power station.
[4]
In a situation where you have an inverter or genny supply, if you don't connect these to earth you cannot receive a shock unless you actually touch both the active and neutral conductors at the same time (and that's not easy to do) as the supply is now isolated from earth.
[5] I have wired my inverter circuit GPOs without an earth (active and neutral only). I welcome any comments from anyone who may be able to correct me if I'm mistaken as to the wiring rules of RCD devices on inverter and genny circuits in van environments .
[6]I would also think that the SAA rules would regard the entire van as an appliance, since it is connected by a removable lead and not hard wired. Therefore it could be connected as an earthed - or a double insulated - appliance which requires no earth connection.
-- Edited by Stratman77 on Monday 22nd of December 2014 02:58:32 AM
Hi
One at a time
[1]
The original ELCBs for commercial use ,worked on the same principle as today's RCDs
THey did measure out of balance currents, between neutral & active ,due to current leaking to earth
They did not measure the actual leakage current in the earth system
They did require ,at least, an EN system not necessarily a M.E.N
I worked for a company that was a very early supplier,as their electrical service man.
It was a different system to the ELCBs used by power companies which did measure ACTUAL earth current
[2]
Yes AND ANY similar circumstance where something becomes live [such as the frame of a van]
[3]
They are not voltage based ,they are current, based but obviously there has to be a return path for the leakage current so a EN bond is required FOR RCDs [ but not for RVDs]
[4]
True
AS long as that "ISOLATED "supply remains FULLY isolated
It only needs needs an insulation failure/ leakage[around 6000 Ohms] or an earth fault ANYWHERE in the system to make the system potentially deadly.
Sadly that has occurred & severe shocks have occurred
Before ELCBs /RCDS safty paks were used in industry [essentualy a transformer with fully isolated winding]
I personaly was involved in investigating accidents/ shock sthat occurred using those
.So I am well aware of the potential for for shocks when isolation is LOST
[5]
Sorry, but you do not have a NEUTRAL YOu can only have a NEUTRAL IF you have an EN link,
otherwise they are simply classed as two ACTIVES/lines
THe recommendation for safe operation of "ISOLATED" supplies is to only ever connect/plug in ONE class 1 device at ant time
THat minimizes the risks of shocks
Mulitpe class 2 devices can be used with a very high degree of safet fronm shocks to earth
[6] The Electrical Standards certainly do not consider a Van"TRANSPORTABLE STRUCTURE" etc as an appliance
I suggest you obtain a copy of AS /NZS 3001"Transportable Structures & their site supplies
It is as supplement to AS/NZS3000
You will find that any hard wired [240V' ]generator or inverter shall have a fully operational RCD
THat is usualy done via a change over switch
If you look at" isolated supplies"in AS/NZS 3000 you will see there are some difficulties in complying with 'Seperation requirements"
if they are to ne maintained as ISOLATED supplies.
HOW could a van ever be considered as an isolated appliance?
It has it's own earthing system
It is a class 1 device
It SHALL be fitted with a 3pin plug
It is usualy full of other class ONE devices
Nowif you are happy to believe that your set up with multiple outlets on the inverter will be realy safe.
[1]now is to find an electrician who is knowledgeable enough to fit the correct protection device.
[2]I use an inverter (not wired into the van) to charge laptop, run a box fan & bug zapper. I'm assuming I have no protection when using the inverter?????
Cheers Pete
Hi Pete
[1]
JUst make sure he tests at EVERY individual 240V outlet socket, that the RCD does trip
it will onlt take a few more minutes
Sadly, many just test @ one
[2] Remember the safety recommendation
Multiple clas 2 which have two pin plugs are quite safe for shocks to" earth"
But Never connect more than ONE Class 1 which always shall have a 3 pin plug
OK. It seems as though I must have slept through many of my electrical theory classes - or simply forgotten it. As I said, I was not suggesting my views were current regulations and was confident there would be many contributors who could set me straight. Having no experience with RVDs, I see that they do offer additional protection where an earth connection is unavailable or not used. However, they have to be used in conjunction with an RCD. What really disturbs me is that I get the impression from reading many posts that there is an expectation that these devices virtually eliminate the possibility of serious or fatalelectric shock. This is a very dangerous fallacy. The devices will interrupt the current flow when the trigger perameters are reached, but there is no guarantee that the level of current flow for that - albeit very brief - period of time cannot cause serious injury or death. I think an annual insulation and electrical test certificate, along with appliance testing would be an excellent addition to the gas inspection. On the other points of dispute, I guess we will have to agree to disagree. I will certainly accept that the classification of vans is certainly covered by regulations unfamiliar to me and would not be regarded as a plug in appliance.
__________________
Best regards,
Chris
Licensed Electrician, Electronics, Gaming & Computer Technician. Now retired and loving it!
Multiple clas 2 which have two pin plugs are quite safe for shocks to" earth"
But Never connect more than ONE Class 1 which always shall have a 3 pin plug
PeterQ
Gday...
Let me firstly state I am only a half a notch above moron when it comes to electricity. But because I do try to gain some understanding about this magical medium called 'tricity ... I constantly read and try to understand these threads in case I need to draw on this stuff from the deep, dark depths of my ageing mind. Even if only to 'recall' the jargon when some sparkie/auto elec is telling me 'his solution'.
I assume the HWS in a van (eg Suburban), absorption fridge (eg Dometic), washing machine and microwave are all "Class 1" appliances - that is they have a three pin plug attached -
When the van is connected to 240V in a van park, the HWS and fridge are working 'all the time' and the microwave is used fairly regularly. The stove has a 240v hotplate which is also used regularly. The washing machine is also used at least twice a week while these other appliances are switched on and drawing power.
From a point of view of genuinely trying to understand 'safety in the van', when you say NEVER connect more than ONE Class 1 appliance does this apply to NOT having those appliances working at the same time?
Again, please keep it simple, and in layperson's terms - I really am only one notch above a moron regarding 'tricity.
Cheers - John
__________________
2006 Discovery 3 TDV6 SE Auto - 2008 23ft Golden Eagle Hunter Some people feel the rain - the others just get wet - Bob Dylan
Multiple clas 2 which have two pin plugs are quite safe for shocks to" earth"
But Never connect more than ONE Class 1 which always shall have a 3 pin plug
PeterQ
Gday...
Let me firstly state I am only a half a notch above moron when it comes to electricity. But because I do try to gain some understanding about this magical medium called 'tricity ... I constantly read and try to understand these threads in case I need to draw on this stuff from the deep, dark depths of my ageing mind. Even if only to 'recall' the jargon when some sparkie/auto elec is telling me 'his solution'.
I assume the HWS in a van (eg Suburban), absorption fridge (eg Dometic), washing machine and microwave are all "Class 1" appliances - that is they have a three pin plug attached -
When the van is connected to 240V in a van park, the HWS and fridge are working 'all the time' and the microwave is used fairly regularly. The stove has a 240v hotplate which is also used regularly. The washing machine is also used at least twice a week while these other appliances are switched on and drawing power.
From a point of view of genuinely trying to understand 'safety in the van', when you say NEVER connect more than ONE Class 1 appliance does this apply to NOT having those appliances working at the same time?
Again, please keep it simple, and in layperson's terms - I really am only one notch above a moron regarding 'tricity.
Cheers - John
Hi, I understood the reply from PeterQ was referring to using an inverter not wired through a protection device.
So if not connected to a 240V outlet at a van park but to a generator (or inverter) then the HWS, Fridge, Washing machine, Microwave, stove hotplate should not be used at the same time?
If using the generator I would only use it for battery charging, through the inbuilt 'smart charger/power supply' (which has a three-pin plug) provided in the van; the hotplate for about 20mins cooking tucker (and not that often ); and maybe the washing machine.
I therefore assume I would be considered "safe" .. or is that still too much to have coming 'connected' to the generator?
Cheers - John
__________________
2006 Discovery 3 TDV6 SE Auto - 2008 23ft Golden Eagle Hunter Some people feel the rain - the others just get wet - Bob Dylan
OK. It seems as though I must have slept through many of my electrical theory classes - or simply forgotten it. As I said, I was not suggesting my views were current regulations and was confident there would be many contributors who could set me straight. Having no experience with RVDs, I see that they do offer additional protection where an earth connection is unavailable or not used.
[1]
However, they have to be used in conjunction with an RCD. What really disturbs me is that I get the impression from reading many posts that there is an expectation that these devices virtually eliminate the possibility of serious or fatalelectric shock.
[2]
This is a very dangerous fallacy. The devices will interrupt the current flow when the trigger perameters are reached, but there is no guarantee that the level of current flow for that - albeit very brief - period of time cannot cause serious injury or death.
3]
I think an annual insulation and electrical test certificate, along with appliance testing would be an excellent addition to the gas inspection. On the other points of dispute, I guess we will have to agree to disagree. I will certainly accept that the classification of vans is certainly covered by regulations unfamiliar to me and would not be regarded as a plug in appliance.
Hi
[1]
Yes, for most purpose they are used with a RCD but can be used on their own for low current applications
But they are more sensitive & they respond to voltage more than current
THey use the RCD as the tripping mechanism
They are, IMHO , far superior to any other existing form of protection from shocks to earth
One of the advantages is that the initial "'Isolation" remains a as a first line of protection
An EN bond is not necessary but they detect when one occurs or exists,
{2]ike all forms of detection, they cannot give protection from line to line or line to neutral shocks,
Like all such protection device,they have to pass very strict standards to ensure they reliably trip At the approved current /time levels
Nothing in live is foolproof, but they do have a test button which performs an electrical test of the unit.
Some Gov depts consider them far superior to RCDs & are fitting ALL their ambulances with them. Where they HAD to use high sensitity,10mA tripping RCDs.
[3] I am all for annual inspections & tests& such is required in NZ for very good reasons ,due to a few differences in their approach to how vans may be wired
It would also catch up with dodgy work carried out by those who do not know/understand the apllicable standards.
But All that such an inspections indicates is that ALL WAS well @ the time of the test
AS the van drive out the door a potentially deadly fault can develop
The only way is to ensure safety is:
"[a] the van is wired fully in accordance with the Standards
Any alterations /Additions are carried out by an electrician who knows the Standards[many do not know they even exist!]
[c]Use the best avaialble shock protection system
[d Then finally ,that rare commodity where electricity is concerned "COMMON SENSE"
So if not connected to a 240V outlet at a van park but to a generator (or inverter) then the HWS, Fridge, Washing machine, Microwave, stove hotplate should not be used at the same time?
[2]
If using the generator I would only use it for battery charging, through the inbuilt 'smart charger/power supply' (which has a three-pin plug) provided in the van; the hotplate for about 20mins cooking tucker (and not that often ); and maybe the washing machine.
[3]I therefore assume I would be considered "safe" .. or is that still too much to have coming 'connected' to the generator?
Cheers - John
Hi John
First, I should make the point you will not be electrocuted just because you have more than one Class1 connected
It needs 2 faults for that to occur The first one can exist without you knowing
The 2nd can be a person, who become the link result, BAM , shock or electrocution
The more Class 1connected the greater the risk of one becoming fauity
[1] correct unless you have shock protection,[ best a" RVD"]
[2]THe battery charger IS the 2nd class1 device
The van itself is the first ,no doubt you have a 240V fridge plugged in that is #3
It realy comes down to what risks YOU are prepared to take
If you wish to do no more than minmize the risks, follow the recommendations, the fewer class one PLUGGED in the better
If you wish to feel realy safe, then do as you no doubt have at home, get Shock to earth protection.
With portable generators plugged into the van inlet socket THAT means a RVD/RCD combo
I am making a little prediction, within the next few years, ALL portable generator will have some such form of earth leakage protection
It is now mandatory for
:ALL that are any hired out
All used on mining, construction & building sites,
Why has that Reg been made ??
Simply because of many shocks & some deaths!
PeterQ
-- Edited by oldtrack123 on Monday 22nd of December 2014 05:38:25 PM
As I stated previously, there is much confusion regarding the provision of home standard protection in a van. See http://www.exploroz.com/Forum/Topic/107454/Electrical_safety.aspx for (a) very comprehensive post(s) on the subject. And once again I highlight the unrealistic expectation apparently held by some that these devices provide absolute protection against electric shock. It is a fact that there have been deaths where a 9v battery has been put on the tongue, so it doesn't require a very high current flow through the heart or brain to be serious. I came from a time where safety packs (isolation transformers) were a mandatory safety precaution in certain environments. Of course any of these devices - including RCDs and RVDs - can fail, dramatically increasing the risk of electrocution anyway. I am not suggesting not to use these devices, just be aware that there are always risks when using electricity - even when they ARE installed and used correctly.
__________________
Best regards,
Chris
Licensed Electrician, Electronics, Gaming & Computer Technician. Now retired and loving it!
Its interesting to read some of the posts on this subject.
From memory, there will be a slight shock for up to 30mS (at full current) before the RCD trips. IF and only IF the person receiving the shock is in a bad state of health (eg. bad heart) and the path the current takes through the body will determine the outcome of that event.
In conclusion, RCDs and RVDs will protect life in the majority of cases, however there will be individuals in bad health who MAY suffer badly or become deceased. In the most cases these devices have saved lives and will continue to do so thank goodness.
Im not sure I agree with the definition of class one and class two appliances, I have seen many class two appliances with 3 pins (earth not connected) the correct definition is the square within square located on the appliance body (AS/NZS 3760:200?)) I believe they stopped producing 2 pins for double insulated devices as manufacturers had returns with the complaint that there were only 2 pins on the plug (conjecture).
Again this is an interesting thread, I wish you all the compliments of the season.
The Crocks
-- Edited by Crockie on Monday 22nd of December 2014 06:31:49 PM
Hi Chris
Regarding the link to" explore OZ'
Bantam is not an electrician & obviuosly has a lot to learn about RCD & RVDs
K& Ft [Frank }is an electrician with RCD experience [In hospitals]
Alan B is an electrical engineer,
oldtrack123 Is an old electrician with years of experience with RCDs
Servicing, fault finding why they were tripping etc when they FIRST came on to the Aus market way back in late 50s early 60s
Also was aware of the development of the RVD, before it came onto the market.[even before it was considered for RV use, but I could see it's advantages even then.if certain problems could be overcome
Those problems are now solved with the various models.
My advice is to have a Licenced Electrician inspect your RV, repair any defects, replace any defective components, and issue an Electrical Compliance Certificate as required by law.
__________________
Retired Airline Pilot and Electrician..
I'm not old, I've just been young a long time....Ken
Since light travels faster than sound, some people appear bright until you hear them speak.
My advice is to have a Licenced Electrician inspect your RV, repair any defects, replace any defective components, and issue an Electrical Compliance Certificate as required by law.
As stated at the beginning of this post, you can have an electrical compliance certificate, issued if the van has an RCD. But an RCD will not protect you if supplying power from a generator.
My van has no protection other than circuit breakers, 1999 vintage. I have learnt from this topic, & will be having an RVD fitted.
Cheers Pete
-- Edited by wasn_me on Monday 22nd of December 2014 09:42:26 PM
I am happy to concede again - as I did in my first post - that I am no expert in the area of current RV & van wiring regulations and appreciate the comments from the above contributors who obviously know a lot more about it than I ever will. I trust all the readers of this forum have gained an understanding of electrical safety issues regarding what should be done to minimise any risk and ensure that not only is the van wiring safe and compliant, but all appliances are also tested and used with due care. It is also clear that it is likely that your neighbourhood electrical contractor may not have the specialist knowledge required to issue a compliance certificate in relation to any wiring other than the mains power circuits, and finding one who does may be difficult. Perhaps this forum may be useful if anyone knows one they could recommend, that would be great.
__________________
Best regards,
Chris
Licensed Electrician, Electronics, Gaming & Computer Technician. Now retired and loving it!
A purely academic response as PeterQ made a reference earlier that there can be no 'neutral' without an earth connection. I understand the concept of calling a connection at earth potential neutral (with respect to earth) which is logical. However, I also accept the concept where we adopt nomenclature to indicate that one source is at a potential difference from another. The idea of naming any two sources with a potential difference between them and where they are totally isolated from any other source as 'active' is illogical. In my opinion, it would be the same as marking both battery terminals 'positive'. But once again, I accept that things change and my ideas are probably very outdated - like me.
__________________
Best regards,
Chris
Licensed Electrician, Electronics, Gaming & Computer Technician. Now retired and loving it!