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| Thread ID: 68753 | 2006-05-10 01:15:00 | Home electrics questions | Greg (193) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 453603 | 2006-05-10 01:15:00 | 1) In this image (www.imagef1.net.nz): a) What is the spike in the ground with the red cable, and b) What is the thing on the wall with the cable leading to/from it? c) Do they present a solution... er I mean a danger to little kiddies that stray onto the property? 2) On my switchboard (www.imagef1.net.nz) there are a couple of switches I don't understand... a) What's a "Hot Water Off Peak Switch" for? b) What's a "Residual Current Device"? c) What is the button above the "Residual Current Device" switch for? Thanks for any enlightenment! |
Greg (193) | ||
| 453604 | 2006-05-10 01:35:00 | The Residual Current Device (RCD) is a device which makes sure that when something (or for that matter, someone) forms a connection between the power supply and the ground, that it will switch off power - usually in a matter of milliseconds. It means that if you get electrocuted, the RCD should trip out fairly quickly so that there is minimal damage to you. There should be a "reset" switch for the RCD, so that when it has been tripped, you can reset it and thus allow power to work again. There should also be a "test" switch which will check to see if the RCD is working properly. It seems as though there is an arrow pointing to the big button which says "test", but I can't quite see clearly on the picture. I have a fair idea as to what the other things are, but I'm not 100% sure so I think it's best for someone like GrahamL or Godfather to answer those questions. |
somebody (208) | ||
| 453605 | 2006-05-10 01:36:00 | 1a: Ground / Earth. Let's hope its a metre long |
bob_doe_nz (92) | ||
| 453606 | 2006-05-10 02:13:00 | This is what an RCD is (en.wikipedia.org) What is the button above the "Residual Current Device This maybe one of the buttons on the Wiki site. |
Speedy Gonzales (78) | ||
| 453607 | 2006-05-10 02:58:00 | It seems as though there is an arrow pointing to the big button which says "test", but I can't quite see clearly on the picture.Yeah there's a label thing that indicates "test". Image 1 (www.imagef1.net.nz) Image 2 (www.imagef1.net.nz) So does this mean that if I get my missus to press the button, um I mean if I, press the button, it'll send a short violent shock through my body, and if I live, the test is successful; if I die, something needs to be reset? :dogeye: |
Greg (193) | ||
| 453608 | 2006-05-10 03:13:00 | Hehe no. If you press the Test button the switch below it should automatically turn off. If it doesn't then you need to get the RCD checked or replaced. How big is the house this switch board is from? Looks like a small amount of switches to me. In my old house (approx 140m squared) we had twice as many switches and 2 RCDs. |
CYaBro (73) | ||
| 453609 | 2006-05-10 03:17:00 | Yeah - the test button simulates what would happen if you were being electrocuted (except in this case, it's a bit of metal or something linking positive to earth). As CYaBro said, it should trip something off. The smaller white button looks like it is probably the reset button, which will need to be pushed to "reset" the RCD such that it will work again. | somebody (208) | ||
| 453610 | 2006-05-10 03:51:00 | Cool. The house is smallish... without digging out the LIM report I recall it's about 140 m square, excluding garage and deck. I actually didn't notice the tiny white button, which'll probably need a pencil or something to press to reset it. Makes sense that it'll be a reset button. Thanks. |
Greg (193) | ||
| 453611 | 2006-05-10 04:18:00 | a) What's a "Hot Water Off Peak Switch" for? For instance we have 2 meters - one for the general house power and one for the hot water cylinder. The cylinder can be changed to use Offpeak pricing from the power company. They (unless you naughtily disable it) can turn your hot water power off. Which they normally do at peak load times. |
pctek (84) | ||
| 453612 | 2006-05-10 04:40:00 | The RCD just compares the current in the phase and neutral wires . If they differ by (usually) 20-30 mA, there's something wrong . The only place any "missing" current can go is "earth", usually through someone holding a faulty device . I suppose it would detect a condition of more current in the neutral than in the phase, too . That might indicate strange things happening . The circuit on the unit shows you what's in it . The test button diverts some of the neutral current through a resistor, and that should trip it (to the "Off" position) . Now you have looked at it, you will have noticed that it should be tested once a month (like that pressure release valve on the WH cylinder . :D) Resetting it will just be the same as the other breakers on that board: just move the toggle to the "On" position . The wire from the earth stake is certainly not red; it's green (or green/yellow) . That red bit is the label saying "Earth Conductor: do not remove" . You can see the green wire going into the round conduit entry box, with probably a black neutral screened cable (power coaxial cable) which is the one carrying the power . The earth stake provides the earth for the whole system . It's quite important for safety . |
Graham L (2) | ||
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