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| Thread ID: 33157 | 2003-05-08 22:20:00 | Ripple switch control | effie C (772) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 142495 | 2003-05-08 22:20:00 | Hi, Have just had my tame tutor in for some correctional work- and he has just advised me to pull the plug/switch off at the wall when not using the computer, in case this ripple interferes with it -- any comments? |
effie C (772) | ||
| 142496 | 2003-05-08 22:22:00 | sorry that should be ripple switch electric heater control if it is utilised in any power board area | effie C (772) | ||
| 142497 | 2003-05-08 22:33:00 | Ripple control signals are in the range of 175 Hz to 1050 Hz, superimposed on the 50 Hz mains. (Most are below 385 Hz) Voltages are in the order of 0.7v to 3 v typically, so should be "invisible" to a PC power supply, which rectifies all incoming voltages to DC anyway. Most signals consist of a number of pulses of the higher frequency (about 0.7 seconds of pulsed signal, with about 10 pulses per signal) It would need to be a VERY dodgy power supply to suffer any interference from a ripple signal. I have never encountered one, and if it were an issue I would know. I have seen problems in very remote areas of the country, which are supplied by "Single Wire Earth Return" (SWER) 6,600 v systems, where there is a resonance issue and these voltages can get up in the tens of volts additive to the mains, but that is a very very rare situation. Almost all areas of NZ have ripple signals on the mains. |
godfather (25) | ||
| 142498 | 2003-05-08 22:49:00 | I endorse Godfather's comments. I think ripple control has also been used for streetlighting control in some areas as well, but apart from the old system interfering with stereo recordings some years ago, I have never heard of any problems with electronic equipment, let alone computers. You used to hear the ripple signal coming from your meterbox many years ago but that is history now. Even though my meterbox still has the old electromechanical resonant switch installed, it seems to operate silently now. Either that or I am deafer than I thought! Refer your Tutor to this thread for a "Heads Up" Cheers Billy 8-{) |
Billy T (70) | ||
| 142499 | 2003-05-08 23:14:00 | its not a bad idea to turn it off at the switch but thats to help stop spikes comming through not the ripple control :) | tweak'e (174) | ||
| 142500 | 2003-05-08 23:35:00 | Thats right tweak'e but it also applies to all the electronic equipment in the home. If you use the normal shutdown switch on your computer, but leave the switch on at the wall, would a spike be a potential danger then, or must the computer be running. |
Smithie 38 (1008) | ||
| 142501 | 2003-05-08 23:43:00 | when you turn off the pc the pc still has power running in it so even if its off it can still get spiked. however you are more likly to get spiked up the telephone line than through the power cable, so a good telephone surge protector is very highly recommended :) | tweak'e (174) | ||
| 142502 | 2003-05-08 23:51:00 | You can actually hear the ripple control signals come through on some cheap bedside clock radios which have poor supply smoothing. | Terry Porritt (14) | ||
| 142503 | 2003-05-08 23:56:00 | Geez tweak'e how can I organise that to happen when mother-in-law is on the phone :D | Smithie 38 (1008) | ||
| 142504 | 2003-05-09 00:22:00 | Ripple control is used extensively for: Peak load control of waterheaters Tariff control (day/night meter register changeover) Night Heating on/off Streetlighting Signalling of high network load periods for major customers Price sensitive shedding of load (drops waterheater load when prices are high) Also some of the later ripple relays automatically drop the load if the mains frequency goes below the allowable limits, and therefore they can be used to provide automated emergency load shedding, which can be useful if a fault knocks a major generator off-line suddenly. |
godfather (25) | ||
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