Currtail Posted March 22, 2011 Share Posted March 22, 2011 In one of our venues the voltage meter on the PA rack regularly reads just over 240 Volts. Everything works ok, as you can imagine, but the lamp life of parcans seems to be significantly reduced. As our dimmers are LD90s I thought that perhaps I can reduce the maximum output voltage from the panel on the front of the dimmers. Can anyone tell me how to do this, or perhaps tell me where I can find an LD90 manual on-line or better still both? Link to comment Share on other sites More sharing options...
boswell Posted March 22, 2011 Share Posted March 22, 2011 Google, 1st hit Link to comment Share on other sites More sharing options...
boatman Posted March 22, 2011 Share Posted March 22, 2011 Assuming you are in the UK, your PA voltage meter appears to be working correctly. Are you using 240V lamps? If you're buying from Europe they'll be 230V and have significantly shorter life. Link to comment Share on other sites More sharing options...
Davethsparky Posted March 22, 2011 Share Posted March 22, 2011 I don't know the ld90's that well but this is unlikely to be possible as the dimming is not achieved by altering the output voltage but by phase angle control. To start with you should make sure you are using 240 volt rated lamps rather than 230 volt. Link to comment Share on other sites More sharing options...
IRW Posted March 22, 2011 Share Posted March 22, 2011 Setting the maximum output voltage can be done, the manual is on the Strand website- Here Specifically, page 64. Ian Max Voltage - This facility allows the max. output voltage to be set for all or individual dimmers. Set max. voltage to that of your lamps, or, set them 10% lower for considerably improved lamp life. PS, if your racks are locked, check out page 62 for how to unlock them. Link to comment Share on other sites More sharing options...
Bryson Posted March 22, 2011 Share Posted March 22, 2011 How much more than 240V? If it's over 253V then you can take it up with your supplier. To be fair to the OP, strandlighting.com appears to be down right now, despite being the first hit on Google for LD90 Manual. Strand Archive to the rescue: http://www.strandarchive.co.uk/control/dimmers/ld90/LD%2090%20install.pdf Page 17 SET > OUTPUT VOLTAGE Just realised that the venue I used to work at with super-high voltage had LD90s. Never knew that function was in there. Must let James (my sucessor) know if he hasn't already worked it out! Link to comment Share on other sites More sharing options...
boswell Posted March 22, 2011 Share Posted March 22, 2011 I got the manual via 1st hit on google no trouble <_< then I posted my reply! Link to comment Share on other sites More sharing options...
Currtail Posted March 22, 2011 Author Share Posted March 22, 2011 Thanks Ian that's great I should be able to sort the problem now. All my bulbs are rated 240V but their life is significantly less in this venue, where the voltage is sometimes consistantly at 241-242V. In the other venues we either have some old Tempus or relatively new ETC sensor, but they are further from the town centre so I suspect the voltage is more reasonable there, the lamp life is definitely more what I would expect. Boswell. I am glad that you are so good at using google but isn't the whole point of forums like this to tap the wealth of knowledge and experience of the people that frequent it? :blink: Thank you everyone else! Link to comment Share on other sites More sharing options...
gareth Posted March 22, 2011 Share Posted March 22, 2011 A 240v lamp should have no problems at 241 or 242 volts. Indeed, those figures are well within the tolerance of the UK mains supply, which is 230v +10% -6% (used to be 240v +/-6% before Brussels got its hands on us <_<). So you could conceivably be seeing 253v at the wall socket and it would still be in tolerance. Link to comment Share on other sites More sharing options...
Brian Posted March 23, 2011 Share Posted March 23, 2011 ... where the voltage is sometimes consistantly at 241-242V. ...There is something odd here. 241-242v is not unusual and I'd warrant that even those figures are wrong just based on the accuracy of your meter. What life are you getting from your lamps? What brand are they? Where do you buy them from? Link to comment Share on other sites More sharing options...
david.elsbury Posted March 23, 2011 Share Posted March 23, 2011 isn't the whole point of forums like this to tap the wealth of knowledge and experience of the people that frequent it? You are quite correct, but the forum helps those who help themselves first- and when the manual is so easy to find, you don't have any excuse for not doing a little research first- makes you appear lazy.... :) Link to comment Share on other sites More sharing options...
sguy42 Posted March 23, 2011 Share Posted March 23, 2011 Our LD90s were not entirely happy set at 240V, we reset them to 250V & they've been fine since. I would not recomend this without having a good idea of your local supply though.Our dimmers are about 30m from the substation and on a heavy load day the voltage drops to about 248V. On light light loads the mains voltage is 252 - 253V, so within tolerances, but only just. Shane Link to comment Share on other sites More sharing options...
robloxley Posted March 24, 2011 Share Posted March 24, 2011 AFAIR 10% overvoltage roughly halves the rated lamplife, whereas undervoltage by 10% roughly doubles it (the exact figures may be off, but the effect is significant). Link to comment Share on other sites More sharing options...
Mexi Posted March 26, 2011 Share Posted March 26, 2011 Have you checked the voltage at the dimmers? The PA rack may be feed from a different distribution board. There will be a voltage drop across the installation, different socket outlets across the venue will have a different voltage present. Coincidentally, at work we have monitored energy usage at various sites - Voltage often decreases at 8:00 (start of work), 10:00 (teabreak) 13:00 (lunch time) and 16:00 (last cup of tea before home time). Its amazing how many locations follow the same profile. Link to comment Share on other sites More sharing options...
dmxtothemax Posted March 27, 2011 Share Posted March 27, 2011 If you lamps are rated for 240v and are running on 240v then you can't do much about it.And a small increase in mains voltage is not usually a problem,As 240v lamps are designed to handle up to 245v.If they where running on 230v before yes you would have got extended life.If your racks have an adjustment for max voltage this could help.But large wattage lamps typically dont have a long life anyway.As they say they dont make em like they used to !. I suspect this is because most lamps are made in china.Even the major names have slipped in the quality area,probably so they can compete with the cheaper imports. Link to comment Share on other sites More sharing options...
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