lights at entrance

Tom Hagen

Trench dug for Eircom out to my front gate. 180meters.

thinking of adding in cable for lights at my entrance on the piers.

can I drop in Swa armoured cable into the trench before I backfill?

what size ye reckon?

its 180meters and powering two led lights on top of piers.

punisher5112

Tom Hagen wrote: »

Trench dug for Eircom out to my front gate. 180meters.

thinking of adding in cable for lights at my entrance on the piers.

can I drop in Swa armoured cable into the trench before I backfill?

what size ye reckon?

its 180meters and powering two led lights on top of piers.

Run normal nym j 2.5 if you think you would ever want to put in electronic gates and 1.5 for lights

Tom Hagen

punisher5112 wrote: »

Run normal nym j 2.5 if you think you would ever want to put in electronic gates and 1.5 for lights

cool thanks.
3 x 2.5 swa cable i have readily available. the local store has it handy. #
will this do the trick?

i am only putting in lights. living rural area on private lane not going with elec gates. i know where ur coming from tho.

punisher5112

Tom Hagen wrote: »

cool thanks.
3 x 2.5 swa cable i have readily available. the local store has it handy. #
will this do the trick?

i am only putting in lights. living rural area on private lane not going with elec gates. i know where ur coming from tho.

Yeah would be fine run it in the ducting shouldn't be any issues.

Tom Hagen

punisher5112 wrote: »

Yeah would be fine run it in the ducting shouldn't be any issues.

can i run this in same ducting with eircom cable? or can i run it in the trench but not in any ducting. swa cable is ok to leave in earth i understand?

punisher5112

Tom Hagen wrote: »

can i run this in same ducting with eircom cable? or can i run it in the trench but not in any ducting. swa cable is ok to leave in earth i understand?

SWA is protected so OK in trench but cable would need to be in ducting.

I've done it without issues but some may have an issue with it.

Tom Hagen

punisher5112 wrote: »

SWA is protected so OK in trench but cable would need to be in ducting.

I've done it without issues but some may have an issue with it.

grand job.

now if i want driveway lights maybe next year or in the future. can i leave a little manhole every 40-50meters with this swa through the manhole so i can tap into this for driveway lights if i want ? is that a good idea

irishkopite 2011

Tom Hagen wrote: »

can i run this in same ducting with eircom cable? or can i run it in the trench but not in any ducting. swa cable is ok to leave in earth i understand?

The swa may cause interference with the Eircom cable if in the same duct. I would put the swa in a separate duct even though it can be directly into the ground.

punisher5112

Tom Hagen wrote: »

grand job.

now if i want driveway lights maybe next year or in the future. can i leave a little manhole every 40-50meters with this swa through the manhole so i can tap into this for driveway lights if i want ? is that a good idea

You could do that or leave a loop at points you feel you might use then connect to a junction box and get the special silicone gel. Can't remember the name but its suitable for submerging connectors and that so no moisture or flooding will be an issue.

Tom Hagen

punisher5112 wrote: »

You could do that or leave a loop at points you feel you might use then connect to a junction box and get the special silicone gel. Can't remember the name but its suitable for submerging connectors and that so no moisture or flooding will be an issue.

not 100% sure on how that works. sounds better than a manhole option tho. but me and my digger driver are dimwits , would be easier for us to leave a little manhole out for future connections along the driveway and let the electrician do his thing down the line. if we leave enough slack in the cable in the manhole he can cut it and add junction box etc can he?

punisher5112

Tom Hagen wrote: »

not 100% sure on how that works. sounds better than a manhole option tho. but me and my digger driver are dimwits , would be easier for us to leave a little manhole out for future connections along the driveway and let the electrician do his thing down the line. if we leave enough slack in the cable in the manhole he can cut it and add junction box etc can he?

Nice of you to think of sparky not many do.

Yes that would be a bang up job.

Tom Hagen

punisher5112 wrote: »

Nice of you to think of sparky not many do.

Yes that would be a bang up job.

right, i ran 3 x 2.5 swa armoured cable all the way from utility room to the front gate for lights on the entrance piers and I left out 5 loops up out of the trench for street lights, staggered out along. (180meter driveway). these are now literally just cocking up out of the clay beside the driveway.

When the time comes, i need to build my street light bases around the loops.

so How does the sparky tap into the swa? does he cut it and use junction box and run a cable up inside the street light to the bulb? just out of interest.

2011

That is a long cable run for such a small cable. This means a high earth fault loop impedance which is only complaint with regulations (to ensure that disconnection times are fast enough) once the MCB (or fuse) is small. A small MCB means that only a small load can be connected. Also the volt drop should be carefully looked at especially with long cable runs to ensure that it is not excessive. Therefore it would be prudent to calculate the maximum load and calculate the cable size accordingly. Also if you are considering installing electric gates it would be an idea to install an intercom cable.

elperello

Tom Hagen wrote: »

cool thanks.
3 x 2.5 swa cable i have readily available. the local store has it handy. #
will this do the trick?

i am only putting in lights. living rural area on private lane not going with elec gates. i know where ur coming from tho.

It won't break the bank to make provision for electric gates now in case you change your mind in future.

Tom Hagen

2011 wrote: »

That is a long cable run for such a small cable. This means a high earth fault loop impedance which is only complaint with regulations (to ensure that disconnection times are fast enough) once the MCB (or fuse) is small. A small MCB means that only a small load can be connected. Also the volt drop should be carefully looked at especially with long cable runs to ensure that it is not excessive. Therefore it would be prudent to calculate the maximum load and calculate the cable size accordingly. Also if you are considering installing electric gates it would be an idea to install an intercom cable.

will be fine for lights. not for electric gates.

2011

Tom Hagen wrote: »

will be fine for lights. not for electric gates.

It probably will be, it depends on the load.
Not having electric gates will reduce the load alright.

Risteard81

punisher5112 wrote: »

Tom Hagen wrote: »

Trench dug for Eircom out to my front gate. 180meters.

thinking of adding in cable for lights at my entrance on the piers.

can I drop in Swa armoured cable into the trench before I backfill?

what size ye reckon?

its 180meters and powering two led lights on top of piers.

Run normal nym j 2.5 if you think you would ever want to put in electronic gates and 1.5 for lights

NJM-J is not suitable for burial.

punisher5112

Risteard81 wrote: »

NJM-J is not suitable for burial.

Never said it was but is if in conduit or ducting suitable.

Risteard81

punisher5112 wrote: »

Risteard81 wrote: »

NJM-J is not suitable for burial.

Never said it was but is if in conduit or ducting suitable.

Unless it is earthed conduit or ducting then it won't ensure ADS operates when the cable is damaged.

2011

Risteard81 wrote: »

Unless it is earthed conduit or ducting then it won't ensure ADS operates when the cable is damaged.

Are you suggesting that the conduit / ducting has to be conductive ?

The red ESB type ducting provides ample protection to underground cabling.

Risteard81

2011 wrote: »

Risteard81 wrote: »

Unless it is earthed conduit or ducting then it won't ensure ADS operates when the cable is damaged.

Are you suggesting that the conduit / ducting has to be conductive ?

The red ESB type ducting provides ample protection to underground cabling.

I am suggesting that really SWA is the most suitable for burial because of the earthed armour (or MIMS because of the earthed sheath).
If you put a spade through NYM-J or Hi-Tuff there is no guarantee of disconnection. Instead you could have a live spade. Ducting will not resist penetration by a spade etc.

2011

Risteard81 wrote: »

I am suggesting that really SWA is the most suitable for burial because of the earthed armour (or MIMS because of the earthed sheath).
If you put a spade through NYM-J or Hi-Tuff there is no guarantee of disconnection. Instead you could have a live spade. Ducting will not resist penetration by a spade etc.

Fair enough, but NYMJ installed in the ESB compliant red duct meets the requirements of the regulations. In my opinion the risk of putting a spade through a cable installed in this manner is minimal for the following reasons:

1) The duct itself provides high impact resistance.
2) The duct is not buried close to the surface. I am open to correction here but from memory the regulations state that it should be buried at a depth of at least 3 feet.
3) A suitable warning tape is buried over the duct.

Apart from the expense I would not be keen on using a metal conduit. Even a galvanized metal duct would rust badly over time particularly at the joins and there would be a lot of joins over 180m.

I'd be very surprised if you got much of a shock from a spade in any case. It's an earth electrode at that point and the person is a parallel high resistance load if the spade is conductive.
Much the same as water isn't as dangerous as people think.

Bruthal

Sir Liamalot wrote: »

I'd be very surprised if you got much of a shock from a spade in any case. It's an earth electrode at that point and the person is a parallel high resistance load if the spade is conductive.
Much the same as water isn't as dangerous as people think.

There would be little shock risk. The spade possibly being in contact with the ground would have little bearing though.

Tom Hagen

2011 wrote: »

It probably will be, it depends on the load.
Not having electric gates will reduce the load alright.

when you say load? would I be better off using LED bulbs in the pier lights and street lights to reduce the load

Charles Babbage

Tom Hagen wrote: »

when you say load? would I be better off using LED bulbs in the pier lights and street lights to reduce the load

In this day and age you would be better to use LED both to reduce the load and your ESB bill.

2011

Tom Hagen wrote: »

when you say load? would I be better off using LED bulbs in the pier lights and street lights to reduce the load

Yes, and as per the above post this will result in reduced running costs.

Bruthal

Bruthal wrote: »

The spade possibly being in contact with the ground would have little bearing though.

Why do you say that? If you only nicked the line I thought it would be relatively significant. The rest of the outcomes are lower risk by comparison.

Bruthal

Sir Liamalot wrote: »

Why do you say that? If you only nicked the line I thought it would be relatively significant. The rest of the outcomes are lower risk by comparison.

Because even a proper earth rod connected straight to an MCB is unlikely to trip it. Earth rods become more effective when they are many, such as in a housing estate being all connected to N, because earth only becomes a good conductor via large surface area, so a shovel making some contact with the ground won't have a huge bearing on changing shock risk.

The shovel in contact with a live point and also earth (soil), will still be at 230v relative to all earth except right at the immediate few inches around the shovel. It's still a 230v point as it would be if no contact with earth. It doesn't drop to earth potential, nor does it bring any real amount of the earth up to 230v. The effect on the level of shock risk is minimal, since even if it was just nicking the live conductor without earth contact, the risk still isn't that high.

Tuco88

Should be on an rcd also for outside lighting if I am correct, unless above a particular hight.