Multi Meter readings

[Paul]

, I need to check my coil but not sure if its faulty, as I'm not sure how to convert the readings..can anyone help me out here

heres what the book says

Heres a close up of the meter

here's the secondary...

Here;'s the Primery

 

[BassCliff]

Hi,

The dial sets the range for the display. I can't tell exactly what the range settings are but it looks like 2 - 20 - 200 - 2000 (K ohms).

If that is so, you've got 25.2K ohms on the secondary, which is good.

You have .006 ohms on the primary (almost a dead short), which is bad.


Thank you for your indulgence,

BassCliff

 

[Paul]

Cliff yep those are the ranges...... so as long as the range is set and it doesnt show a 1 on the left of the display the range is set correctly and no conversion is nessessary, just a simple case of reading the number?

Thanks
Paul

 

[rustybronco]

His scales are 2,000Ω (2KΩ), 20,000Ω (20KΩ), 200,000Ω (200KΩ) and 2,000,000 (2000KΩ)

It appears that the meter is set to read on the 2,000 Ω scale so 1,000 (1K) X .006 = ?

If the meter had a 0-20Ω scale you could read the numbers directly.

 

[rustybronco]

Have a look see... http://www.ehow.com/how_7525409_read-multimeter-ohms-ranges.html

Set the multimeter to the setting "2K" (1 Kilohms) on the dial if the component is between 1,000 Ohms and 2,000 Ohms. The digit to the left of the decimal represents whole thousands of Ohms, while the first digit to the right of the decimal represents hundreds of Ohms. The second digit to the right of the decimal represents tens of Ohms, and the third digit to the right represents single-digit Ohms.

For example...

2. = 2,000
1. =1,000
.1 =100
.01 =10
.001 =1

 

[Steve]

I am seeing that as .006K ohms, which is 6 ohms. A little high, but since it's at an extreme end of the scale, it's probably OK.

Even with (supposedly) accurate digital meters, it's not wise to trust the accuracy at either end of the scale.

.

 

[rustybronco]

And we also don't know if his DVOM has the capability of zeroing out the leads resistances.

Yes 1000 X .006 = 6

 

[eil]

I agree with Steve, the selector dial is pointing at K ohms, so 0.006 = 6 ohms.

BTW, if you're in the market for a high-quality yet relatively cheap multimeter that's easy to read and does auto-ranging, I've had this one for a few years and I lurve it: http://www.amazon.com/Mastech-MS826...TF8&qid=1361420665&sr=8-1&keywords=multimeter

 

[BassCliff]

Hi,

Yes, looking at it again I agree. On the 2K range .006 would be 6 ohms (not 0.6 ohms), just a little higher than spec for the primary.

Please forgive my mis-perception. Carry on.


Thank you for your indulgence,

BassCliff

 

[Paul]

I agree with Steve, the selector dial is pointing at K ohms, so 0.006 = 6 ohms.

BTW, if you're in the market for a high-quality yet relatively cheap multimeter that's easy to read and does auto-ranging, I've had this one for a few years and I lurve it: http://www.amazon.com/Mastech-MS826...TF8&qid=1361420665&sr=8-1&keywords=multimeter

Thanks, I've been looking at multi meters for a while, they sell the same model here in the UK, so I will be buying one.

 

[Paul]

Hi,

Yes, looking at it again I agree. On the 2K range .006 would be 6 ohms (not 0.6 ohms), just a little higher than spec for the primary.

Please forgive my mis-perception. Carry on.


Thank you for your indulgence,

BassCliff

Thanks again, I've ordered a new one so hopefully this will be able to eliminate one possible cause of my 250 running rich and peforming poorly :-k

 

[barnbiketom]

that coil is
GOOD not bad...

 

[Paul]

that coil is
GOOD not bad...

the order had been placed by the time we sorted that.. no harm in keeping it as a spare (learning curve)

 

[barnbiketom]

Thats cool!
If you put that meter on the lowest ohms scale and hold the leads together, it 'should' read ZERO. ....

if it reads for example...1.5 then your reading will be 1.5 ohms high..

I use a Harbor freight meter and it reads almost TWO ohms with the leads shorted out!!! .. nothing to worry about if you know what's goin on!!

I'm not sure which bike you are working on, but the fuel system is always suspect for ill running conditions.

Carb to intake orings and the carb's internals !!

 

[Steve]

Thats cool!
If you put that meter on the lowest ohms scale and hold the leads together, it 'should' read ZERO. ....

if it reads for example...1.5 then your reading will be 1.5 ohms high.

Agreed. Also, just so you know, even calibrated meters will show a resistance when the leads are shorted together.

That will be the resistance of the leads, themselves. My Fluke is calibrated annually for work, and it will typically read 0.2 or 0.3 ohms when the leads are shorted.

.

 

[Paul]

This is an ebay buy (GN250) thats been sat for 15years, I've ultrasonic cleaned the carb a couple of times, and followed basscliffs methodology, I fited a carb kit yesterday, no new diaphram (slide boot in the US?) but it seems to me to be supple and in good order , so I'd pulled the coil and RR off to check and clean while waiting for the kit (Keyster brand), done the Compression (which ain't great). Tomorrow I'm going check the valves clearances and fit the carb and electrics back. Then if its still running bad I'll open another thread in "Other Bikes" with a status report, and go from there.

Then once we fixed this we can start to look at the GS...then the fun starts all over again

Now using my newly gained knowledge I'm going to test the resistance in the RR.....so dont rush off anywhere

Thanks Everyone!!

 

[Paul]

So based on what i now know....is it safe to say this regulator needs replacing?

setting for a x1 ohm readking, test by touching pos and neg together for a 0.00 reading on this setting...then returns to 1,

The Book!

The test.... this was + to R and - to Bl, it was the same nil reading for everything else!!

Cheers!!

 

[barnbiketom]

hmmm.
first off I see no bl wire.
I do see a white/blue stripe or a blue with white stripe.
You should get an infinite reading (where it says 'off')on those combinations and readings of 7-8 ohms or 65-85 ohms on the others.
for example:

- on blue/white stripe, and + on red Should give 65-85 ohms....
that is only one combination in the picture.. the very bottom left says minus (-) on blue/white and at the top up from 65-85 it is RED on the +

You'll notice that combination with the leads reversed, ( diferent combination with the leads) should give 'off' (to me that is infinity) or OPEN or whatever YOUR meter reads with the leads open, not touching!!

Take all those tests and you'l see if it is good.

BUT i wonder why you are testing it???

A bad rect/reg will affect the chargingcof the battery.

With a charged batery, the bike should run ok till it goes dead.

You need to check the votage on the battey with the bike running to see the charging..maybe you did and I missed this???

 

[barnbiketom]

this would be two tests... using the red wire and the blue/white.

same two wires getting checked but just reversing your leads for the second test.

kind of hard to get the jist but I tried to make a picture hahaha

 

[rustybronco]

So based on what i now know....is it safe to say this regulator needs replacing?

setting for a x1 ohm readking, test by touching pos and neg together for a 0.00 reading on this setting...then returns to 1,

You have no x1 setting on your DVOM. You have a diode/continuity position. Use that position as the 2KΩ (that your meter shows set on) more than likely will not have enough current flow to turn on the diodes