hadyn.williams Posted February 28, 2008 Share Posted February 28, 2008 Hi folks, Have searched Martin's website and been through the Mac 250+ manual but can't find out how many amps they will draw when the lamps strike? I know it will vary depending on what lamp you have etc. but a rough estimate from someone would be great! Sadly I don't have the fixtures available to me at the moment, otherwise I would use a clamp meter to check, but I have to work out my power requirements before they arrive with me! Thanks! H Link to comment Share on other sites More sharing options...
maeterlinck Posted February 28, 2008 Share Posted February 28, 2008 I don't actually know the answer here, but from the way you ask the question I wonder if you need to. Unless you're planning on striking all your lamps at the same time then you're unlikely to pop your trip as long as you have a reasonable overhead on the circuit. The AutoStrike feature may be your friend here as it will vary when each unit strikes its lamp. I think 400W is a good figure to start with for a per unit draw. For instance 6 on a 13A socket is comfortable - 80% capacity.HTH Link to comment Share on other sites More sharing options...
browna Posted February 28, 2008 Share Posted February 28, 2008 Hi, I sure that the lamps on a 230V supply, ignite with 1.8A. thanks! browna Link to comment Share on other sites More sharing options...
Ynot Posted February 28, 2008 Share Posted February 28, 2008 I sure that the lamps on a 230V supply, ignite with 1.8A. Erm, no.Discharge lamps will strike with a higher current than their normal running level, so whilst the fixtures will happily devour around that level when working normally, the strike/ignition current can and will be far higher. Hence the need for them to be switched on individually or in small numbers. Link to comment Share on other sites More sharing options...
Sirch Sound Posted February 28, 2008 Share Posted February 28, 2008 Hi, I will be able to check for you on saturday if you can wait that long? Rich Link to comment Share on other sites More sharing options...
hadyn.williams Posted February 28, 2008 Author Share Posted February 28, 2008 my estimate was around 2amps although someone from AC lighting suggested at one instant they can take up to 80amps... I certainly can wait until saturday so it would be fantastic if you can find out! Thanks folks, much apreciated. Link to comment Share on other sites More sharing options...
KevinE Posted February 28, 2008 Share Posted February 28, 2008 Just from experience of the ammeter at the end of the workshop bench, a typical 150W MH scanner gives a brief ( half second) kick at around 4 amps dropping to about 2A for a couple more seconds. This is just a guesstimate from memory BTW as peak / transient currents arent easily measured with an analogue meter..and different fixtures are bound to react differently. Link to comment Share on other sites More sharing options...
Cougar Posted February 28, 2008 Share Posted February 28, 2008 I was once told that they struck at around 6 amps but have never seen documentation to back that up! Remember that you don't have to strike them all at the same time so as long as the total running current does not exceed your supply minus the strike current of the last fixture you can get away with quite a lot more than the strike current suggests. Link to comment Share on other sites More sharing options...
Ike Posted February 29, 2008 Share Posted February 29, 2008 Hi, I will be able to check for you on saturday if you can wait that long? RichJust to be an awkward so and so how exactly are you going to measure something that is so depend on the lamp, its temperature, the point in the cycle its struck, residual flux in the ballast and the impedance of the source? Also are you going to measure it for the first cycle, two cycles, second or two? I suspect there are a few very good reasons why martin don't publish this information. :D That said I can see a few graphs of current consumption being interesting from a purely academic point of view if anyone has the time and kit to produce them, I just can't see them being of much practical use. Link to comment Share on other sites More sharing options...
Steve Cavill Posted February 29, 2008 Share Posted February 29, 2008 On strike they pull around 6a on a 240v supply, or 10a on a 120v supply. Hence the main fuse being 6.3a @ 240v or 10a @ 120v All this information is published in the manual for the fixture, as with all manufacturers. Link to comment Share on other sites More sharing options...
Ike Posted February 29, 2008 Share Posted February 29, 2008 It isn't really that simple I'm afraid. The main fuse specified is a 6.3A time delayed type that can (from memory) carry about 20A for one second or 100A for 0.01 seconds. As pointed out above the actual current will depend on a lot of different factors and may also be very tricky to measure. Link to comment Share on other sites More sharing options...
live Posted February 29, 2008 Share Posted February 29, 2008 I usually install 4 x mac 250's or 300's on a single 15a type c and have not yet had a problem with any of my install's. It isn't really that simple I'm afraid. The main fuse specified is a 6.3A time delayed type that can (from memory) carry about 20A for one second or 100A for 0.01 seconds. As pointed out above the actual current will depend on a lot of different factors and may also be very tricky to measure. Spoken like a true pro! :D Link to comment Share on other sites More sharing options...
Sirch Sound Posted March 2, 2008 Share Posted March 2, 2008 Hi, I will be able to check for you on saturday if you can wait that long? RichJust to be an awkward so and so how exactly are you going to measure something that is so depend on the lamp, its temperature, the point in the cycle its struck, residual flux in the ballast and the impedance of the source? Also are you going to measure it for the first cycle, two cycles, second or two? I suspect there are a few very good reasons why martin don't publish this information. :o That said I can see a few graphs of current consumption being interesting from a purely academic point of view if anyone has the time and kit to produce them, I just can't see them being of much practical use. Yes, I agree that the will be some fluxtuation in the results, but I will try my best to get an average reading and state specs of the lamp used ect. If a margine for error is built in then surely having some idea of the strike current will be useful, especialy considering there is a varying of opinion from 6a upto 80a! On strike they pull around 6a on a 240v supply, or 10a on a 120v supply. Hence the main fuse being 6.3a @ 240v or 10a @ 120v All this information is published in the manual for the fixture, as with all manufacturers. If your correct about this being published then great but as ike says, there is alot more to it that just the fuse ratings. It isn't really that simple I'm afraid. The main fuse specified is a 6.3A time delayed type that can (from memory) carry about 20A for one second or 100A for 0.01 seconds. As pointed out above the actual current will depend on a lot of different factors and may also be very tricky to measure. Yep, macs do have a slow blow fuse in them, and I belive its closer to 200a at 0.01 seconds and about 30a for 1 second, theres a time to amp graph somewhere on the tinternet, il have a google and post the link, its a very handy graph! Oh and sorry I diddnt get a chance yesterday to pull a mac out but I will see if I can spare some time during the week. CheersRich EDIT: Heres the graph, its a PDF. Link to comment Share on other sites More sharing options...
Ike Posted March 2, 2008 Share Posted March 2, 2008 Yes, I agree that the will be some fluxtuation in the results, but I will try my best to get an average reading and state specs of the lamp used ect. If a margine for error is built in then surely having some idea of the strike current will be useful, especialy considering there is a varying of opinion from 6a upto 80a!If you just want a rough idea I'd say you'd be looking at around five or six amps decaying logarithmically over a few seconds possibly preceded by a high current surge of around twenty milliseconds or so. I suspect the initial surge will vary to much for you to be able to draw anything remotely useful from however if you could exclude this from your results you may be able to get something with a reasonable degree of accuracy for a given lamp, ambient temperature etc. Link to comment Share on other sites More sharing options...
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