HELP, my RCBO trips

[Anthony5]

I have 8 lamps on my perimeter wall. When I light them up the RCBO will trip. Some days it will, some days not, and it isn't depending on rain because after working for 2 dry days the third day the RCBO trips.

 

I have figured out that the fault is inside the wall, not on the powerline leading to the wall.

 

The lights are mounted at the top of the wall, where each light has a plastic junction box, which is cemented into the wall and then covered with cement and stone.

 

So far I have opened all the lights and removed the sockets but I can't see anything unfamiliar, so probably it will be in the connections in one of the junction boxes.

 

Is there a way to figure out which junction box is the issue without having to open them all?

[bankruatsteve]

That's the only way I know.  Easiest to find when it is tripping... Start at the farthest out box, disconnect L & N, see if it trips, clean it out, repeat the next one, etc.  Actually, best in any case to open all the boxes and clean out whatever might be in there.

 

If you find a box full of gecko shit/eggs, that's probably the one.

[Anthony5]

All sockets are disconnected, and the RCBO still trips.

[bankruatsteve]

You said you had junction boxes?  Anyway, it's most likely a fault where the wires connect.

[Anthony5]

Yes I said I have junction boxes, which are covered with cement and stone, so opening them up is not an easy job. It involves hammer and chisel, replacing every box I attempt to open.

[bankruatsteve]

Well, for future reference, junction boxes must be accessible.  So, the wires to the lights disappear into the boxes?  If there is connection at the light, you could check those.  Otherwise, that will be a bitch to solve.

 

[Anthony5]

Well aware of this, hence the question if there is a way to figure out which box with the use of a multi meter.

 

The lights are mounted to the wall, with the wires going up to the junction box at the top of the wall, where they are connected to each other.

[bankruatsteve]

Your problem is that you don't have any way to isolate anything.  Maybe Crossy will be along with some thoughts.

[Crossy]

Are there actually joints in the junction boxes or are the joints at the lamps? If you can split the circuit half way and see if it still trips you can then identify which half is problematic.

 

You're unlikely to see anything with a regular multimeter, you really need an insulation tester.

 

OR You could replace the lights with low-voltage LED units and drive from a transformer in a nice dry location.

[bankruatsteve]

Crossy, just curious... having only used a borrowed insulation tester many years ago I'm not that familiar with them.  Is there a way to connect one other than the "standard" way - which I don't see available in this case?

[Anthony5]

20 minutes ago, Crossy said:

Are there actually joints in the junction boxes or are the joints at the lamps? If you can split the circuit half way and see if it still trips you can then identify which half is problematic.

 

You're unlikely to see anything with a regular multimeter, you really need an insulation tester.

 

OR You could replace the lights with low-voltage LED units and drive from a transformer in a nice dry location.

 

 

Yes the joints are in the junction boxes. Actually the lamps inside are the Osram saving lamps which have a small 1w led in the front. When you open the light the led light up. When you then switch off and switch on again the the savings lamp lights up.

 

I actually use them only in the led function, as I have no intention to light up the public road outside my house.

 

Edit : The multimeter I have has a 2000uF and a 2Mhz setting

[Crossy]

My pragmatic solution = Get some 12V 1W or 2W lamps to replace the mains ones and run them from a transformer / power supply.

 

At 12V the gekko or damp won't cause issues.

 

[Anthony5]

3 minutes ago, Crossy said:

My pragmatic solution = Get some 12V 1W or 2W lamps to replace the mains ones and run them from a transformer / power supply.

 

At 12V the gekko or damp won't cause issues.

 

 

I think that is indeed the easiest way. What is the size of such a transformer? I have a larger junction box where the wire that comes from the fuse box in the house connects photocell and so to the wires in the wall, but not sure if enough place inside.

 

Otherwise I guess I can just place the transformer on top of the fuse box, since it is a dedicated circuit for those lights only.

 

Any suggestion where to purchase the lamps and what should be the price?

 

 

[Crossy]

I would look at automotive lamps, something like these http://www.satisled.com/5050-smd-g635-led-light-12vdc-input-13led-25w_p1559.html

 

A power supply adjustable 12-18V or so (size depends upon how many lamps and what wattage) would allow you to set for 12V halfway down the string for best light distribution.

[Anthony5]

1 hour ago, Crossy said:

I would look at automotive lamps, something like these http://www.satisled.com/5050-smd-g635-led-light-12vdc-input-13led-25w_p1559.html

 

A power supply adjustable 12-18V or so (size depends upon how many lamps and what wattage) would allow you to set for 12V halfway down the string for best light distribution.

 

 

Thanks for the link Crossy, but it looks like they require specialised sockets. Aren't they available in regular sockets yet?

 

Since English isn't my native language I'm also confused with half way down the string. I guess that mean the transformer should be placed somewhere in the middle, which is actually not an option. I only can place it at the start where the circuit from the house enters the wall, and from there it is split in 2 circuits that consist of 3 and 9 lights each. Would that be an issue?

 

As I said the current lamps have a single led at the front of the bulb, which is 1 or 2 Watt, and that is sufficient for my needs

 

 

[Anthony5]

Just found these Crossy. The seller told me they work on anything between 12 and 24V.

 

Is that possible and would that be a solution because I can't place the transformer in the middle?

 

http://www.ebay.com/itm/E27-E26-E12-G9-E14-B22-12V-24V-110V-220V-5W-White-Warm-Light-Cover-LED-Corn-Bulb-/261820815648?var=&hash=item3cf5bc9920:m:mklMtRpJSo79IDGmkakhVzw

[Anthony5]

OK, found also these LED lamps, which have the SMD 3014 chip.

 

http://www.ebay.com/itm/1x-High-Quality-E27-48-3014SMD-LED-Bulb-Warm-White-lamp-light-AC-DC12-24V-3W-BS-/181723671310?hash=item2a4f932b0e:g:KGAAAOSwJQdW-imf

 

This chip has a heat sink according to Wikipedia. Should that be an advantage over the SMD 5730 or SMD 5050?

https://en.wikipedia.org/wiki/SMD_LED_Module

 

I also found this LED driver, which is waterproof, so not to worry about moist.

 

http://www.ebay.com/itm/DC-24V80W-IP67-waterproof-Power-Supply-Driver-Transformer-AC-TO-DC-For-LED-Light-/391547883587?hash=item5b2a129043:g:-LYAAOSw8oFXx4Hg

 

Are the above items suitable for my project?

 

Would a power supply as in the picture below be moist proof if that would happen? I have such a 24V type laying around and the junction box it will be placed in rarely get wet, even when it rains.

 

There is now a 20V power supply in the box, which feeds infrared beams, so maybe I could replace that and feed lamps and beams from the same power supply if I tone it down to 20V? Or isn't it possible to tone it down 4V?

 

 

 

 

[Crossy]

Good research there Anthony.

 

Those lamps look good to go, interesting that you can get a 12-24V lamp with an E27 fitting, very handy for those who want to retro-fit like you. Being wide range like that they should also solve any volt-drop issues over your existing wiring. Do ensure you get the colour you want, warm or daylight.

 

How long is the wiring run, what size wire?

 

I don't think I'd trust that driver to be IP67, bit it's certainly ok for a simple box outside if necessary.

[Anthony5]

4 hours ago, Crossy said:

Good research there Anthony.

 

Those lamps look good to go, interesting that you can get a 12-24V lamp with an E27 fitting, very handy for those who want to retro-fit like you. Being wide range like that they should also solve any volt-drop issues over your existing wiring. Do ensure you get the colour you want, warm or daylight.

 

How long is the wiring run, what size wire?

 

I don't think I'd trust that driver to be IP67, bit it's certainly ok for a simple box outside if necessary.

 

Wiring to the furthest point is about 35 meter, and I can't see the writing on the wire anymore, but it looks like 1.5mm solid copper.

 

The link you provided, added with the 2 I found, we have 3 different types of LED's. Is there an advantage of one over the other I should choose?

 

Can a 24V transformer easily be reduced to 20V, by soldering a resistor or so, so that I can use it for both lamps and infrared beams at the same time?

 

Do I need to add a certain factor when calculating the wattage needed for the transformer?

 

Is there a difference in using DC or AC output regarding to the moist issue, or doesn't that make a difference in low voltage? I assume that if I use DC I have to take polarity into account, where this isn't needed with AC.

 

Sorry for the multiple questions, but we're almost there.

[Crossy]

How many of what wattage lamps will you be using?

 

I would just go with lamps that look ok and are the right colour. Ones with a frosted cover will give a more even light..

 

You wouldn't just use a simple resistor dropper, but it's not rocket science to drop 24V DC to 20V DC (how much power do the sensors use?).

 

I would oversize the power supply by 10% or so.

 

AC or DC makes little odds with the moisture, the lamps may or may not be polarity sensitive (but it's easy to check and wire them right).

[Anthony5]

39 minutes ago, Crossy said:

How many of what wattage lamps will you be using?

 

I would just go with lamps that look ok and are the right colour. Ones with a frosted cover will give a more even light..

 

You wouldn't just use a simple resistor dropper, but it's not rocket science to drop 24V DC to 20V DC (how much power do the sensors use?).

 

I would oversize the power supply by 10% or so.

 

AC or DC makes little odds with the moisture, the lamps may or may not be polarity sensitive (but it's easy to check and wire them right).

 

 

I will have 12 lamps in total, and I consider to go with the 3 Watt ones from the last Ebay link (SMD 3014). With a seller with a 99.9% rating I guess you can't go wrong.

 

The beams use DC 12 -20V or AC11-15V and 100mA x 10 beams.

 

I have now a 19V DC 4.7A PC transformer to power them. Could I use that transformer to power the lamps as well?

[Crossy]

 

12 x 3W lamps @ 19V is 2A or so, let's say 2.5A for a bit of headroom (this assumes the lamps have constant-power electronics within).

 

So you could happily use your existing power supply for the 3.5A load (1A for the beams).

 

Volt drop would put about a 2V drop by the end of your 35m run, the lamps should be happy at 17V instead of the 19 at the start of the run

 

Looks like we have a plan

 

 

[Anthony5]

1 minute ago, Crossy said:

 

12 x 3W lamps @ 19V is 2A or so, let's say 2.5A for a bit of headroom (this assumes the lamps have constant-power electronics within).

 

So you could happily use your existing power supply for the 3.5A load (1A for the beams).

 

Volt drop would put about a 2V drop by the end of your 35m run, the lamps should be happy at 17V instead of the 19 at the start of the run

 

Looks like we have a plan

 

 

 

 

A cunning plan :-)

 

What is constant power electronics, and how do I check for that?

[Crossy]

Found this handy volt-drop calculator http://www.epanorama.net/index.php?index=calc_cable

 

Does US and metric wire sizes as well as copper, aluminium and silver conductors.

 

[Crossy]

3 minutes ago, Anthony5 said:

A cunning plan :-)

 

What is constant power electronics, and how do I check for that?

 

The LEDs themselves need a constant-current source to drive them correctly. Many of the 12V units just use a resistor (inefficient and the drive current varies with the supply voltage). I suspect that the relatively high-power (3W) and wide supply range (12-24V) would indicate something a little more comprehensive within.

 

You could try asking the seller (good luck) or simply assume they are, you're not going to fry anything if they are resistor based.

[Anthony5]

On 9/21/2016 at 2:10 PM, Crossy said:

 

The LEDs themselves need a constant-current source to drive them correctly. Many of the 12V units just use a resistor (inefficient and the drive current varies with the supply voltage). I suspect that the relatively high-power (3W) and wide supply range (12-24V) would indicate something a little more comprehensive within.

 

You could try asking the seller (good luck) or simply assume they are, you're not going to fry anything if they are resistor based.

 

Seller confirmed that the lamps use constant power electronics.

 

Just ordered 14 piece ( 2 spare) 3W AC/DC 12~24V SMD 3014 frosted cover for a total of $43 include shipping

 

http://www.ebay.com/itm/-/172350557026?