Hi James, Do you have any links that show what you mean? When you talk of rise time is that at switch on? And peak current the same? There are LEM products that measure DC, I use them all the time at my current job. Best Regards Luis On 28 Feb 2015 17:56, "James Holland" wrote: > > From: Luis Moreira > > Subject: RE: [EE] Injector Testing > > > Hi James, > > Not quite the question I was asking, I have access to plenty of tools > like > > that one at the moment. In fact I use one like that from fluke all the > > time, I also have some tektronix ones. > > I am more interested on the manner of the testing. > > I deal mostly with 4 cylinder vehicles and although I intend to expand > this > > test setup to 6,8 or even 12 cylinders, this is ideal to get the > > measurements into a four channel scope, which will show the four > injector > > signals and timing in relation to each other. In my opinion in one go I > > could get quite a lot of info just from this. The breakout box would > allow > > me to observe the injector signals with them still connected to the ecu= .. > > Observing the current would also give me info on injector resistance an= d > > any other issues. > > As an example, I am looking at a Vauxhall Vivaro, which had a confirmed > > faulty injector changed. After they changed it, the problem is still > there > > and instead of a cylinder X miss fire I get a intermitent injector > control > > short circuit fault. I suspect the bad injector may have damaged the EC= U > > output driver stage/current sensing circuit, but before I send the ECU > for > > repair I need to reassure myself that the rest of the circuit > > (wiring,connectors and injectors) are fine under load, Now getting to t= he > > injectors on a van like this is a pain and I only want to remove all th= e > > bits to get to them a couple of times. With a breakout box I would get > all > > the info at once. > > As I haven't found any setup like this I am just wandering if this as > worth > > while thing to persue. > > Thank you. > > Luis > > On 27 Feb 2015 18:10, "James Holland" wrote: > > > > The breakout box is a good idea but I don't see a big advantage of having > multiple current probes. It should be pretty easy to spot a bad injector > from its current waveform if its an electrical failure rather than a > blockage; the peak current and the rise time tell you all you need to kno= w. > The LEM sensors that I've looked at measure AC current only, if you do > decide to build a setup then sensors that can measure the DC component as > well would give a better representation of the waveform. > James > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .