Starter solenoid current?

Agreed, this has been an interesting thread with a lot of good information. BTW, a common failure on (I'm going to say earlier, but we're talking 80's and later) VWs is the inline spade connector to the solenoid. Corrosion builds in that connector resulting in a high resistance joint. This got me on my Cabriolet (an 88) a few years ago. Someone here pointed out what the likely problem was and he was correct. Because the solenoid does draw a lot more current than one realizes any resistance is a big problem.

The clamp meter shows just 5A peak in the solenoid. I suspect that's the average over about 0.1 seconds; which is about how long it takes to close the contacts that pull in the starter fully.

The 5A is the highest peak out of about 20 (*) successive starts. I suspect that that's an average over the sampling period. Figures are scattered all over the place; from 0.3A up to 5A. Most in the 3 to 5A range.

I'll have to put the digital scope with linear Hall-effect sensor on the wire to find the peak inrush current.

(*) Don't want to cook the starter motor with too many successive starts without a reasonable cooling off period.

You would be real lucky if the clampl meter had a sample rate as high as 10 Hz - many seem to have a sample rate of less than one per second! Cheers,

Paul Saccani, Perth, Western Australia

Put a 7 amp fuse in line and crank the engine. If it doesn't blow you pretty well know it;s less than 12 amps (fuse can take about 60% overcurrent for several seconds)

The PROPER fast blow instrument fuse IS there to protect the meter - and IS generally effective. Using a standard or slow blow fuse WILL fry the meter. NEVER replace the meter fuse with other than the proper quick-blow meter fuse.

Nope. Unless they work different when they are upside-down, and I didn't notice that effect in Livingstone.

I'm sorry, but with the greatest of respect, you do not know what you are talking about.

Again, I point out that you do not know what you are talking about.

I've just been describing what *actually* happens with the specified fuse (which presumably, you wish to ignore), and that the function of the fuse is for personnel protection.

Please read IEC 61010, specifically the section dealing with fault clearance by fuses.

Replacement with a lower current value HRC fuse can protect both the meter and the user, with no reduction in safety.

As I pointed out, this is usually not the case in reality. Device protection is generally achieved with VDRs.

Never mind the fact that properly selected ones will not only *not* fry the meter, they actually provide better protection.

Too bad if the specified fuse doesn't actually do its job! And replacing it actually enhances both meter and personnel protection.

Someone thinks the fuse in the meter protects the user, which is not the case. Whether the fuse is there, blown, or not in existence, the hazards are the same. The fuse is intended to protect the meter from excessive currents, and nothing else.

Please read IEC 61010, specifically the section dealing with fault clearance by fuses.

This is not at all true. Which you would know if you had a better understanding of fault currents and what they do.

That is not the case. But, please, don't let the facts intrude onto your reasoning process.

**This'll do the trick:

You should be able to borrow one from your local sparky. Most have them now, though DC rated ones are a little rarer. Auto electricians have them. Or should.

Have one similar out in the garage. Much easier to use.

I already offered him a loaner. He prefers not to borrow equipment.

You can't fault that.

>

A group of us used to share equipment. Had all manner of things. If we needed something, we'd pool our resources and just buy it. Trouble is, most members of the old group have shuffled off their mortal coils now. I was one of the youngsters in the group. Actually, come to think of it, I am the youngest that's left out of the few who "were" young'uns. Ah well, I'm a tad too knackered to be crawling around and under cars now. Best leave it to the next generation I guess!