Testing charge coil voltage with a multimeter.

steviecops

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Hi<br />In one of the books I have it says that to test charge coil voltage, I have to use a multi meter with a mercury DVA adapter, (part number 91-89045), which converts AC voltage to DC voltage that the multimeter can read.<br /><br />I've been looking to buy a new multimeter, and most of the half decent ones seem to be able to measure AC voltage. Do I still need to use the mercury DVA adapter with one of these multimeters, or would they work O.K on their own?<br /><br />If I stll need an adapter, where can I get one, and how much do they cost?<br /><br />Thanks in advance.<br />Steve
 

rodbolt

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Re: Testing charge coil voltage with a multimeter.

hello<br /> yes you can buy a meter that already has a DVA installed. its a peak reading setting. it reads the voltage peaks not the average value. I have one from merc,an old analog meter that I prefer to digital for taking trigger and charge coil readings, I also own 2 stevens cd-77 meters I also own 2 radio shack ones and a fluke. all have properties that I like depending on the application. I have also found my KV tester for DIS ign systems to be invaluable at rapidly fing the bad cyl. just takes practice in interpeting the blinking lamps:)<br /> good luck and your looking for a "peak" reading not just ac.
 

rodbolt

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Re: Testing charge coil voltage with a multimeter.

hello<br /> seahorse<br /> that ESI meter looks excactly like the one merc sold me for 39 dollars in 92 or so. works well. if you need to use the - polarity just switch the leads and it will still read. good luck and keep posting
 

steviecops

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Re: Testing charge coil voltage with a multimeter.

Thanks for the info.<br /><br />I'll go to my local electronics outlet and ask for a suitable multimeter for what I need to do.<br /><br />Thanks again<br />Steve
 

seahorse5

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Re: Testing charge coil voltage with a multimeter.

Rodbolt,<br /><br />Do you mean the meter or the DVA adapter was $39 back then? ESI does make the Merc adapter, from what I was told.<br /><br />I use the Rapair DVA adapter with my Fluke meters since they were available and priced right at that time.<br /><br />Steviecops,<br />You need to ask your electronics outlet for a peak-reading voltmeter for stators and CDI ignitions.
 

rodbolt

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Re: Testing charge coil voltage with a multimeter.

seahorse. the whole meter. its the same meter that is in the sierra catalog now.I know the new CD-77 I bought the otherday was an eye-opener. the last I bought were about 120 apice now its almost 200.but I sent one of my old ones to Venezuela along with a s-48 sparktester and an old radio-shack DVM. for peak reading especially if its an intermittant problem I still use the analog meters. I wish I still had my old simpson 260. oh well<br /> I just bought a manometer kit from precision tools for 177 with shipping. I will post as soon as I see how it works. the yamaha one is now 625 dollars.
 

steviecops

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Re: Testing charge coil voltage with a multimeter.

Thanks seahorse, that's what I'll ask for. I just get the feeling that I'm going to get blank expressions when I ask! Nobody seems geared up over here for outboard repair.<br /><br />I've been looking at multimeters that measure DC and AC voltage, and have a data hold, max-min memory facility. Is that the same as a peak reading facility? Some of them have a bar graph on the display too.<br /><br />Thanks again<br />Steve
 

rodbolt

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Re: Testing charge coil voltage with a multimeter.

no<br /> peak reading is peak reading. most meters read avarage voltage.<br /> its hard to explain about working voltages and how they are figgured and in the case of a capacitor discharge its not technically an ac voltage but has properties similar to ac. IE a rapid rise and fall of the voltage. if you look at the chargecoil waveform as it comes from the coil (unloaded) it will be a true ac wave. once attached to the CDI unit it will shunt one half of the wave. the CDI in its simple form rectifies the ac and stores it in a capacitor (now DC). when the scr, a voltage controled current controling device, is triggered it allows the cap(now dc) to discharge into the coil primary windings. once the scr is triggered it cannot be turned off. it has to wait until the current from source to drain reaches cutoff. then the process starts all over and the scr waits for the next trigger voltage input. <br /> so back to the direct voltage adapter. what this adapter does is amplifies,if you will, the peak it sees to a known value so the meter can read a true voltage.or a "peak".the average or working voltage is .714 or so of the peak. most full wave and all half wave rectifires allow voltage spikes unless filtered and further processed.so most meters do not look for peak voltage and use an average voltage, most digital meters do not react fast enough to see a peak. that is why they have to use an adapter. an analog meter will respond to peaks and intermittants that the digital never shows due to the digital circuitry.<br /> hope this helps a bit its all kinda fuzzy anymore. the navy and an explosives plant I worked for spent a lot of money on my schools that I dont use much any more due to the simplicity of outboard and general boating circuits.<br /> good luck and keep posting.<br /> PS if ya really wanna drive em nuts ask for a Vacum Tube Voltmeter. its much more precise than a standard VOM as it does not load the circuit.
 

steviecops

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Re: Testing charge coil voltage with a multimeter.

Thanks for that explaination Rodbolt. It's slowly starting to make sense. Even an internet search on U.K sites isn't turning anything up with regard to DVA or CD ignition testers.<br /><br />Would it be worth my while looking at motorcycle supplies and equipment? I would imagine that some 2 stroke motorcycles must use the same CD ignition as outboards.<br /><br />Thanks<br />Steve
 

seahorse5

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Re: Testing charge coil voltage with a multimeter.

Steviecops,<br /><br />Check out http://precisionmfgsales.com/ for the test equipment that you need. They carry Stevens, Rapair/CDI, and Merc-O-Tronic testers for outboard ignition systems, and other tools and parts that you might need. Great folks to deal with!
 

rodbolt

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Re: Testing charge coil voltage with a multimeter.

hello<br /> trons is trons. once you understand electronics a bit you will find it does not matter if its two stroke or four, the beauty about trons is theydont care much about who made it or where they are. kinda like internal combustion engines. there are specific laws governing how things work.<br /> if you work with it long enough and take careful notes you will find its incredibly simple.<br /> when you decide which meter to buy use it on everything,especialy things that aint broke. make notes.<br /> this aint voodoo but it does require experience. use it on your car ign coil primary. use it on the injectors to see what peak they get. use it make notes and remember. the only exception is LUCAS stuff. I know why they call LUCAS the prince of darkness :)
 

steviecops

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Re: Testing charge coil voltage with a multimeter.

Thanks again for the good advice. As soon as I can get my hands on what I need, I'll set about gaining a much better understanding.<br /><br />However, it's proving almost impossible to source a DVA adapter or CD ignition tester over here. I spent an hour today with the yellow pages and phoned around dozens of dealers, most of whom didn't even know what I was talking about! I sent 3 emails last night to dealers in the States to see if I could get something shipped over, and so far I've had no replies. (must be busy with the election! ;o)<br /><br />I'll keep trying, and thanks again for your help.<br />Steve
 

steviecops

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Re: Testing charge coil voltage with a multimeter.

I thought I read on here that i-boats shipped good abroad? I've sent them email to ask for a DVA multi meter to be shipped over, and they haven't replied.<br /><br />Could someone shed some light on this?<br /><br />Thanks<br />Steve
 

rodbolt

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Re: Testing charge coil voltage with a multimeter.

hello<br /> call Tony at shore flyte marina in camden NC. area code is 252 338 7724 tell him Tom in kitty hawk told ya. he is from england and ships internationally. he is also a mariner dealer among other things. he has an email and I think its on the net someplace. he can hook ya up with a CD-77 or the merc equivalent either one.<br />good luck and keep posting.
 

steviecops

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Re: Testing charge coil voltage with a multimeter.

Thanks Rodbolt, I'll give him a ring.<br /><br />Steve
 

steviecops

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Oct 3, 2003
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585
Re: Testing charge coil voltage with a multimeter.

O.K, I have finally got myself a DVA multimeter ;o)<br /><br />I ordered one through my local parts dealer and he got me a Quicksilver one.<br /><br />Thanks for all your help.<br />Steve
 
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