multimeter

[Anonymous]

my clymer manual shows an analog meter to test the stator output (looking for over 75 volts). the "stator pages" demand a digital multitester be used. so i tried my analog meter and the needle jerked around a lot and never showed the necessary voltage. my charging system is giving me no trouble, but i wanted to monitor it anyway. my question: will an analog meter give faulty readings like mine did, or am i discovering a problem with my stator? do i in fact have to buy a digital meter? thanks

[92G]

I don't think the analog meter will give a "faulty" reading, but it may give you someting a little different. Did you have in on ACV or DCV?

I can't think of anything that I can do(voltage wise) with a Digital Meter as compared to an Analog meter.

Terry

[Anonymous]

multimeter

i had it on ac. the "stator papers" on this site insist that a digital multitester be used for the test. i wonder if they know something i dont. maybe the analog needle cant keep up with the waveform of the stator while a digital meter will show the peaks.

[Anonymous]

It's all in the response

Analog meters tend to respond more slowly thereby smoothing out the readings you are getting.

A digital one will read instantanious voltage. Could borrow one from a friend.

[Anonymous]

miltimeter

thanks for the response. i did buy a digital meter y'day. i just discovered my signal generator resistance reading is about 410 ohms and should be between 290-360 ohms. i just rode the bike for 1/2 hour and it runs great. i wonder if this could be causing the intermittent "engine misses" problem i have posted elsewhere.

[Anonymous]

The only difference between an analog and digital mulitmeter is the method of display. Sounds like the meter is bad or you are not making the reading properly.

[Anonymous]

multimeter

the digital meter i just bought is a "true" rms digital multimeter. reading true rms voltages, (and current), allows a digital meter to read distorted waveforms (possibly for a stator) accurately, whereas the analog meter cant read true rms waveforms. i can only assume that's why "the stator papers" insists on using a digital meter. i've been wrong before though. thanks again swanny.

[Anonymous]

RMS stands for Root Mean Squared. What is happening is the signal is first squared which in effect moves all of the sinusoidal waveform above the reference (so that you don't get zero for an answer when you do the next step), then you take the mean of the signal, then finally the square root (to counter the fist squaring operation).

I don't have data on all of the meters out there, but quite possibly your meter cannot read the RMS of a 'non-sinusoidal' waveform. That would be a guess, especially if it is a cheap one. I should be able to read sinusoidal waveforms however - stick it into the household outlet and check it.

Maybe after work I can go to some web sites and look at their meters.

[Hap Call]

Re: multimeter

the digital meter i just bought is a "true" rms digital multimeter. reading true rms voltages, (and current), allows a digital meter to read distorted waveforms (possibly for a stator) accurately, whereas the analog meter cant read true rms waveforms. i can only assume that's why "the stator papers" insists on using a digital meter. i've been wrong before though. thanks again swanny.

Actually, analog meters (quality meters such as a Simpson Meter) are used to read distorted wave forms because they tend to damped the reading and not just give a mash of unreadable numbers...they are used a lot on pulse width modulated AC drives. It sounds like the meter you have is just not up to the task.

With little capacitance or inductance influence and no load, the wave form from the stator should be a clean one when you are at 5000 RPM.


Hap

[Anonymous]

There are differences between analog and digital VOM's. Analog meters generally have a lower OHM's per VOLT rating, from 1000 to 20,000 OHM's/VOLT ( Simpson 260 series). Digital meters generally have 1,000,000 to 20, 000,000 OHM's/VOLT rating (Fluke series meters). What this means is this: A lower O/V rating will cause the meter to "load" the output of a device or an electronic circuit, the meter is a circuit in itself. A meter with a higher O/V rating will not affect the circuit, it will seem transparent to the stator or electronic circuit, due to high resistance of the meter input.
Analog meters require current flow thru the meter coil to cause the needle to deflect.
Digital meters sample the voltage and require very small current flow, digitize those samples into representitive levels from 0-255 or 0-1027, depending on meter accuracy.
Inexpensive analog VOM's can have ratings as low as 1000 OHM's/VOLT, which can affect readings.
However, I cannot say for certain a digital meter is essential for checking a stator, voltages on the fault finding chart are quite low, in the tenths of a volt, an inexpensive meter could produce an inaccurate reading.
Check this fault finding .pdf at ElectrexUSA, it only mentions a multimeter.

http://www.electrexusa.com/electrex_fault_finding.html

http://www.electrexusa.com/electrex_stators.html

If the Stator Pages dictates a digital meter, I would use a digital meter. Good meters are available from MCM Electronics (Fluke), Radio Shack (model 22-810 $19.00). II think a good meter can be bought for 20-25 dollars, the elaborate meters can cost around 400.00. This is the .pdf manual for the Radio Shack 22-810, it is 3 1/2 digit, 1 Meg Ohm input.

http://support.radioshack.com/support_meters/doc66/66016.pdf

http://r3.us.rmi.yahoo.com/rmi/http://www.radioshack.com/product.asp/rmivars%3ftarget=_top?catalog%5Fname=CTLG&category%5Fname=CTLG%5F011%5F008%5F002%5F000&product%5Fid=22%2D810

If you need accuracy, 4 1/2 digital meters are better than 3 digit meters, for general troubleshooting a 3 digit meter should work fine in the 20-25 dollar range.

Hope this helps.

Mister T

[Anonymous]

multimeter

my analog meter is a simpson 160 (older model i believe). 20,000ohms/vdc,,,,5,000ohms/vac...i used it to read house voltage and it's fine. i'll have to try it again on the charging system on my bike. i did buy an "extech 22-816" from radio shack y'day and my bikes charging system is ok. i did get 2 diferent readings on my signal generator resistance depending if the bike was hot or cold though. is that normal? cold reading=340 ohms(within spec...,,,hot reading=410 ohms(out of spec). the extech was $89 marked down to $59-i figured i'd get personal feedback on it and if it's so-so i have 30 days to return it. it has: true rms, autorange, 4000 count, temp probe, frequency & capacitance function, relative zero, data hold, backlit lcd, duty cycle, continuity & diode test, overvoltage cat III, input impedance 7.5 m ohm(vac & vdc) .. what do you think for $59 ?