Discovered two extension leads wired with active and neutral reverse wired at the socket end. Now put right, wired correctly. Off a friends caravan, and connected to the house, no RCD's etc. Nobody had received any jolts, everything in the van worked OK. What could have happened to persons in the van, or touching the van outside?
The leads were given to them by neighbors up the road, quite good condition except for that.
iana said
08:07 AM Jun 23, 2020
No I am sure there was no neighborhood feud going on !
PS earth connection was good.
erad said
08:14 AM Jun 23, 2020
As long as the Earth wire is correctly connected, the system is safe enough for normal conditions. The Active wire supplies power to the load, the Neutral returns the current back to the grid. With AC power, which colour of wire doesn't matter - the voltage fluctuates between positive and negative all the time. With DC power that would be a totally different case.
Residual Current protection measures the difference between Active (supply) and Neutral (return), and if there is any significant difference, it trips the breaker. If there is a major fault, the Earth wire is there to provide an easier path to Earth than going through your body.
Possum3 said
08:28 AM Jun 23, 2020
All caravan owners should have their electrical leads and caravan power outlets tested or do it themselves with a readily available tester. www.jaycar.com.au/power-point-and-earth-leakage-tester/p/QP2004
Quite a few (newish) caravans I have tested for others has active and neutral reversed - which make a mockery of caravan manufacturers electrical sign-off. Using unskilled labour in the industry is rife - one manufacturer is actually advertising for unskilled employees to wire and plumb van/motorhomes.
dorian said
08:30 AM Jun 23, 2020
There are some cases where this situation may be dangerous.
If someone has their fingers inside an appliance which switches only the active side of the supply, then the appliance will remain live when the switch is off.
If this extension cable is connected to another cable or appliance where the neutral and earth wires are reversed, and if there is no ELCB, and if the appliance has an earthed metal frame, then there is a potential for electric shock.
iana said
08:48 AM Jun 23, 2020
Interesting, I know when everything ran in reverse with 3 phase, its just a matter of swapping a wire around (except earth) to change direction. Just was unsure of what happens with single phase.
Whenarewethere said
09:07 AM Jun 23, 2020
A good reason to buy & use moulded leads.
Tony Bev said
02:06 PM Jun 23, 2020
Hi Ian
As you know I am not a techi
I am led to believe that modern caravans should have been fitted with
GPO outlets which have, double pole switch that disconnects both the Active and Neutral, to reduce the chance of electric shock
This is in case someone, has wired up a caravan 240 volt plug/switch wrongly
Any switch/plug wired wrongly, could and have (in the past), been killers
I am sure that the electricians, can explain it much better than me
herks said
06:56 PM Jun 23, 2020
Would not be too concerned with only leads being reversed. Have seen some CV park outlets also reversed. How do I know? I have a simple 3 pin plug (available from Bunnings) which you simply plug into a power point and the LED lights will tell if the er is a problem. I have it plugged in and turned on in a power point in the van and as soon as I plug into an external power source and the green leds change then I know there is a power issue.
-- Edited by herks on Tuesday 23rd of June 2020 07:09:48 PM
-- Edited by herks on Tuesday 23rd of June 2020 07:11:29 PM
Mamil said
08:27 PM Jun 24, 2020
If active and neutral have been transposed either at the van park supply or the connection cord to the van everything will operate normally - appliances won't blow up or motors run backwards! However, if normal 'household' GPOs, switches, and circuit breakers have been used then even when the switch is off and the appliance not operating, the circuit will still be live from the source, through the appliance, and back to the switch. This can be dangerous in specific fault situations. This is why the regs (AS/NZS3001 Clauses 3.3.1.2, 3.6.2, 3.6.3.1) say all AC switches, GPOs and circuit breakers on a caravan must be double pole, ie. switch active and neutral, rather than being single pole 'household' type.
-- Edited by Mamil on Wednesday 24th of June 2020 08:52:06 PM
Aus-Kiwi said
01:40 PM Jul 2, 2020
Just be aware if lead has reverse ? It MAY have been corrected at fuse box etc . ?? If its wired wrong and you dont know when it was ? Get the whole van checked for polarity. Why they have double post switches !! Its isolates both !m
oldtrack123 said
07:32 PM Jul 31, 2020
Aus-Kiwi wrote:
Just be aware if lead has reverse ? It MAY have been corrected at fuse box etc . ?? If its wired wrong and you dont know when it was ? Get the whole van checked for polarity. Why they have double post switches !! Its isolates both !m
Discovered two extension leads wired with active and neutral reverse wired at the socket end. Now put right, wired correctly. Off a friends caravan, and connected to the house, no RCD's etc. Nobody had received any jolts, everything in the van worked OK. What could have happened to persons in the van, or touching the van outside?
The leads were given to them by neighbors up the road, quite good condition except for that.
PS earth connection was good.
Residual Current protection measures the difference between Active (supply) and Neutral (return), and if there is any significant difference, it trips the breaker. If there is a major fault, the Earth wire is there to provide an easier path to Earth than going through your body.
Quite a few (newish) caravans I have tested for others has active and neutral reversed - which make a mockery of caravan manufacturers electrical sign-off. Using unskilled labour in the industry is rife - one manufacturer is actually advertising for unskilled employees to wire and plumb van/motorhomes.
If someone has their fingers inside an appliance which switches only the active side of the supply, then the appliance will remain live when the switch is off.
If this extension cable is connected to another cable or appliance where the neutral and earth wires are reversed, and if there is no ELCB, and if the appliance has an earthed metal frame, then there is a potential for electric shock.
A good reason to buy & use moulded leads.
As you know I am not a techi
I am led to believe that modern caravans should have been fitted with
GPO outlets which have, double pole switch that disconnects both the Active and Neutral, to reduce the chance of electric shock
This is in case someone, has wired up a caravan 240 volt plug/switch wrongly
Any switch/plug wired wrongly, could and have (in the past), been killers
I am sure that the electricians, can explain it much better than me
Would not be too concerned with only leads being reversed. Have seen some CV park outlets also reversed. How do I know? I have a simple 3 pin plug (available from Bunnings) which you simply plug into a power point and the LED lights will tell if the er is a problem. I have it plugged in and turned on in a power point in the van and as soon as I plug into an external power source and the green leds change then I know there is a power issue.
-- Edited by herks on Tuesday 23rd of June 2020 07:09:48 PM
-- Edited by herks on Tuesday 23rd of June 2020 07:11:29 PM
If active and neutral have been transposed either at the van park supply or the connection cord to the van everything will operate normally - appliances won't blow up or motors run backwards! However, if normal 'household' GPOs, switches, and circuit breakers have been used then even when the switch is off and the appliance not operating, the circuit will still be live from the source, through the appliance, and back to the switch. This can be dangerous in specific fault situations. This is why the regs (AS/NZS3001 Clauses 3.3.1.2, 3.6.2, 3.6.3.1) say all AC switches, GPOs and circuit breakers on a caravan must be double pole, ie. switch active and neutral, rather than being single pole 'household' type.
-- Edited by Mamil on Wednesday 24th of June 2020 08:52:06 PM
Ditto