ChasB
Well-Known Member
The thread here on earth leakage has made me wonder if my boat is up to standard. How do I check?
How do I check my earth leakage?
- Thread starter ChasB
- Start date
Jean
Well-Known Member
Generally you don't, you simple check the installations potential to "leak" by checking the insulation resistance with an appropriate tester. It's not though just the installation that can "leak" as both fixed and portable appliances connected to the installation all have the potential to "leak" too. Not easy to fully test some of these without risk of damage. If you have a 30mA RCD fitted to your installation (and have it periodically tested) and it does not trip, then you can assume that your installation is OK, at least in this respect.
savageseadog
Well-Known Member
Not quite sure what thread you're talking about but if it's anything to do with electrical safety and you don't know how safe it is, pay an electrician.
ChasB
Well-Known Member
If I had to employ an expert to check for every little problem that might come up I'd be bankrupt in 3 months!
I was just wondering if there was a quick way of checking. I'm going to ask around the marina if anyone's got a 16A 30mA RCD. Maybe persuade the marina to buy one?
Hold on... Isn't there one built into the pontoon mains supply anyway? Two trip switches - one big, one little.
I was just wondering if there was a quick way of checking. I'm going to ask around the marina if anyone's got a 16A 30mA RCD. Maybe persuade the marina to buy one?
Hold on... Isn't there one built into the pontoon mains supply anyway? Two trip switches - one big, one little.
Jean
Well-Known Member
Marina supply may well have one fitted, but do they get it periodically tested? There is a legal requirement for campsites to have theirs tested but not sure if it yet applies to marinas. Have a close look at the marina "big trip switch" and see what it is.
hightech
Well-Known Member
Currently Marinas do not come under the regulations (16th edition), so there is requirement for periodic testing, however, I think that most marinas worth their salt would get a sparky in to test the installation and negate an possible law suits etc.
The olnly way to properly test an RCD is with an RCD tester. The push "T" button only tests that the unit is mechanically sound and does not test what would happen in reality if you got plugged into the circuit! RCD testers are not cheap, a decent sparky/electrical company would have one and be able to make the correct test, however they generally only work on dry land!
The olnly way to properly test an RCD is with an RCD tester. The push "T" button only tests that the unit is mechanically sound and does not test what would happen in reality if you got plugged into the circuit! RCD testers are not cheap, a decent sparky/electrical company would have one and be able to make the correct test, however they generally only work on dry land!
VicMallows
Well-Known Member
[ QUOTE ]
I was just wondering if there was a quick way of checking. I'm going to ask around the marina if anyone's got a 16A 30mA RCD. Maybe persuade the marina to buy one?
[/ QUOTE ]
Perhaps a safe solution might be to provide an RCD in your own circuit anyway? NETTO recently had the 30mA plugin-with-a-socket type at the ridiculous price of £3.99 (and yes, I have checked it's calibration!). Depending on sensitivities, the marina one if present might or might not trip first, but so what.
I could tell you how to effectively test an RCD, but don't intend to get drawn into a heated discussion on safety/regulations/ insurance /etc etc.
Vic
I was just wondering if there was a quick way of checking. I'm going to ask around the marina if anyone's got a 16A 30mA RCD. Maybe persuade the marina to buy one?
[/ QUOTE ]
Perhaps a safe solution might be to provide an RCD in your own circuit anyway? NETTO recently had the 30mA plugin-with-a-socket type at the ridiculous price of £3.99 (and yes, I have checked it's calibration!). Depending on sensitivities, the marina one if present might or might not trip first, but so what.
I could tell you how to effectively test an RCD, but don't intend to get drawn into a heated discussion on safety/regulations/ insurance /etc etc.
Vic
DaveS
Well-Known Member
[ QUOTE ]
The push "T" button only tests that the unit is mechanically sound and does not test what would happen in reality if you got plugged into the circuit!
[/ QUOTE ]
I don't think that's entirely fair. Pushing the test button is designed to cause an out of balance current of slightly more than the trip value, which should in turn trip the breaker thus confirming its correct operation. It is perfectly true that in relying on this you are making the assumption that both the design and construction of the device are to spec. Now it is perfectly true that the only way of obtaining independent confirmation of this is to use a proper RCD tester, BUT lets apply a little realism here. Most people buying, say, a new car (every bit as potentially lethal as faulty switchgear) would rightly expect it to be built to spec., and wouldn't for a moment think about commissioning independent testing of it. You expect a reputable manufacturer's products to perform to spec. and would rightly demand redress if this proves not to be the case. Why regard the humble RCD any differently?
The push "T" button only tests that the unit is mechanically sound and does not test what would happen in reality if you got plugged into the circuit!
[/ QUOTE ]
I don't think that's entirely fair. Pushing the test button is designed to cause an out of balance current of slightly more than the trip value, which should in turn trip the breaker thus confirming its correct operation. It is perfectly true that in relying on this you are making the assumption that both the design and construction of the device are to spec. Now it is perfectly true that the only way of obtaining independent confirmation of this is to use a proper RCD tester, BUT lets apply a little realism here. Most people buying, say, a new car (every bit as potentially lethal as faulty switchgear) would rightly expect it to be built to spec., and wouldn't for a moment think about commissioning independent testing of it. You expect a reputable manufacturer's products to perform to spec. and would rightly demand redress if this proves not to be the case. Why regard the humble RCD any differently?
Jean
Well-Known Member
I agree Dave, the “test button” on RCD does give a crude check, at least of current operation and BS7671 regulation 514-12-02 (IEE Reg's) recommends testing via this facility quarterly, and yes, if RCD still in spec, it’s a good guide. Only sure way to test fully to spec is though with the timed current injection, but not needed at such frequent intervals (say every 5 years if it was fitted in a domestic situation for example).
