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| Thread ID: 70148 | 2006-06-23 14:44:00 | More heating cuts | george12 (7) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 465496 | 2006-06-23 14:44:00 | Did anyone else in Wellington notice the hot water turn off from 10pm to 12am tonight (technically last night)? It's annoyed me terribly as I really wanted a shower. | george12 (7) | ||
| 465497 | 2006-06-23 15:49:00 | How come you've got seperate electricity for lights etc and for water heating? :confused: | Greg (193) | ||
| 465498 | 2006-06-23 21:01:00 | How come you've got seperate electricity for lights etc and for water heating? :confused: Have you not heard of Ripple Control Greg The most common method of controlling hot water is ripple control. Houses with a ripple control have a normal meter and a separate relay which is connected to the hot water system. The lines company can delay the start of hot water heating by sending a ripple or pulse down the power line which signals the relay to switch off. A similar pulse turns the relay back on. |
Safari (3993) | ||
| 465499 | 2006-06-23 23:22:00 | Did anyone else in Wellington notice the hot water turn off from 10pm to 12am tonight (technically last night)? It's annoyed me terribly as I really wanted a shower. What had happened in your household that you didn't have about 130L of hotwater already sitting in the tank? |
PaulD (232) | ||
| 465500 | 2006-06-24 00:29:00 | Controlled waterheating is designed for storage waterheating systems. They will retain the hot water for a day, depending on the use. If you are using a califont type "on-demand" hot water system for the shower, it should not even be on the ripple control circuit though. A 2 hour cut should have no effect on a storage system, unless all the water had already been used (in which case it would still be almost cold, even with the power on). Typically "off peak" ripple control will have winter "off" periods of ~4 to 6 hours per day, up to 12 hours per day in adverse times (like this week). Appropriate sized storage cylinders cope with this just fine. Many have "night rate" only, where the power is on to the water cylinder from 11pm to 7am. On a 185 litre low pressure cylinder this is fine in most cases. |
godfather (25) | ||
| 465501 | 2006-06-24 00:37:00 | What had happened in your household that you didn't have about 130L of hotwater already sitting in the tank? Ours usually only takes about an hour to heat up again - my brother had had a long shower at about 9.30pm - 10.30pm (he does that...). |
george12 (7) | ||
| 465502 | 2006-06-24 01:55:00 | We have gas... :blush: | dolby digital (5073) | ||
| 465503 | 2006-06-24 02:18:00 | Sounds like a "quick recovery" storage system, where there is an extra upper element for a limited quantity in a hurry, provided power is on. Lock your brother in his room after 9:30, should fix it. |
godfather (25) | ||
| 465504 | 2006-06-24 03:26:00 | It's called "ripple control" because after the first system (which used a timeswitch on the switchboard) the switches were operated by sending an audio frequency tone which vibrated a resonant reed . That worked a ratchet wheel through half a revolution . You used to hear the ripple . The new system sends out "telegrams" with commands . There is a carrier of about 175 Hz, and each telegram takes about a minute, at one bit/second . They can switch a particular area, depending on the zone address stored in the EEPROM in the unit . There is a computer in it of course . :D It's used for street light control, too . |
Graham L (2) | ||
| 465505 | 2006-06-24 05:37:00 | The new system sends out "telegrams" with commands. There is a carrier of about 175 Hz, and each telegram takes about a minute, at one bit/second. My turn to be pedantic GL (though nothing you state is incorrect). Frequencies used in NZ are from 175 Hz to 1050 Hz, and tend to be different in each network area to avoid interference. Only Christchurch uses 175 Hz, and that signal covers much of the SI (or did, when 66 kV injection was used but probably less so now they have reverted to 11 kV injection) The "telegram" that takes about a minute (Telenerg protocol) is an exception to the norm though, the Decabit protocol is by far the most common and takes ~ 7 seconds to complete a 10 bit command telegram (common), or ~15 seconds for a double order command (rare). The old Plessey Rythmatic telegram was ~ 10 seconds long, but also being phased out as ripple receivers (relays) are no longer made for that system. The higher (e.g. 665, 710, 1050 Hz frequencies are largely being phased out as propagation is poor, more common frequencies are in the lower range e.g. 283 Hz, 317 Hz with new replacement relays and injection equipment. There are still a few pockets of old "DC Balance" relays about as well, where a small amount of DC is injected into the power system at a local level. A very old and unreliable system though. Without "ripple control", it is likely that domestic power costs would be significantly higher, as it allows better use of the generation and network capacities that exist. |
godfather (25) | ||
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