Charge check

[WMWS]

Is the easiest way to tell how many amps the generator is putting out is to put the leads across the cut out?

[Ed H]

I use to ground the fields for a couple of seconds. This bypasses the reg. Not sure if this will work on A's. Did on all the rest.

[pAAt]

No, I would take it to Mitch's if I were that close !

[WMWS]

I would like to go to Mitch's but down town Philadelphia no thanks.

[Mitch]

Get a trailer

[Jeff/Illinois]

I watched the Army-Navy game Saturday and it was snowing like crazy in that part of Pennsylvania! Yow! So, if you go to Mitch's, better use an enclosed trailer don't drive on those salted slushy roads!!

[Tom Wesenberg]

Yes, but as soon as you remove the terminals from the cutout and connect them to the ammeter, the current will flow, so start the engine quickly and read the meter.
As soon as you read the meter, then you can shut it down and disconnect the meter. Don't attach the lights/horn terminal for this test.

[WMWS]

Tom if I just leave the cut out hooked up and jump my multimeter across it would it not give me a good reading. I have a modern diode cut out.

[Tom Wesenberg]

The diode is a path for current, so the meter would only be showing part of the current.

[Mitch]

What about checking for volts at the generator output stud or across the battery

[WMWS]

My amp meter is showing about 7 to 8 amps when driving. My battery only shows about 6.3 volts. It is a new battery. I'd like to know if my amp meter is accurate or if I need to turn up the charging rate a little.

[Tom Wesenberg]

My amp meter is showing about 7 to 8 amps when driving. My battery only shows about 6.3 volts. It is a new battery. I'd like to know if my amp meter is accurate or if I need to turn up the charging rate a little.

My original ammeter is very accurate.
If I didn't use an electronic voltage regulator, I'd set the ammeter to show about 2 amps.
If I did night driving, then I'd adjust it for more amps to power the lights.

[WMWS]

Ok so I hooked up the multimeter disconnecting the cut out. There are two wires coming out of the generator. One goes to the cut out and the other is grounded to the gen. case. So I hooked the meter to the wire that would go to the rear of the cut out and the other lead to the wire that would go to the front of the cutout. The lights etc. were also disconnected. I got no amperage reading with the engine running about 1500 rpm. Also when hooked up like that I had no reading on the Amp Meter in the car. Next I tried a voltage reading across the battery. With the engine stopped it was about 6.33. With the engine running at 1500 RPM it read about 6.44. Why don't I get an amperage reading and do you think the generator is working. I guess I could see if the lights dim when I turn the engine off.

[Mitch]

Your voltage went up so it's putting out.. Check your voltage also at the cut out where the light and horn connection is. It should be within of about .5 volts of what your reading was at the battery.

At 6.44 volts your putting out about 5 Amps

[Bob C]

You said you were getting no amp reading. Did you switch the red lead on your meter to the AMP socket from the volt ohm socket??

Bob

[WMWS]

Yes

[Tom Wesenberg]

How many amps is your multimeter capable of reading?

BTW, you have a later generator since it has 2 wires coming out the hole.

[WMWS]

My multimeter goes to 20 amps.

[Mike V. Florida]

Take the car wires off the cutout. Connect the meter in between the cutout and the harness. So you would have the generator to the cutout, the cutout to the meter the meter to the harness.

[BILL WILLIAMSON]

For a SIMPLE, QUICK test, jist rev it up & look at the AMMETER!
Dad Simple

[WMWS]

Yes Mike V that is how I hooked it up but got no reading. A friend had an (inductive) Amp meter that you lay over the wire. I layed it on the wire coming out of the cut out and it showed about 4 amps. Maybe the amp part of my multimeter does't work. Bill my amp meter in the car shows about 7 amps when I rev it up.

[Mitch]

You might want to check to see if the fuse is blown in your multi meter. Most all have one for protection when reading amps. If the meter was hooked up wrong when doing a test this will blow it.

[WMWS]

Your right Mitch. The 20 amp fuse is blown. I will get another and re test.

[WMWS]

I got a new 20 amp fuse for my multimeter and retested. Getting 5.5 amps out of the generator on the multimeter and 7 amps on the amp-meter. I think that will be fine as I don't have the lights on much.

[Mitch]

[Tom Wesenberg]

Is your meter supposed to have that large a fuse?
Most meter movements are very sensitive and swing to full scale with very little current, so they are often protected by a fuse of less than one amp.

[WMWS]

Yes it has two fuses. The one is twenty and the other is a mini fuse I don't know the rating. Can I check it by doing a continuity check on it or can I check it by using a test light through a battery.

[Tom Wesenberg]

Yes it has two fuses. The one is twenty and the other is a mini fuse I don't know the rating. Can I check it by doing a continuity check on it or can I check it by using a test light through a battery.

What continuity are you wanting to check?

[tbirdtbird]

I have seen some multimeters with the hi amp range fused, and others not fused, and with a warning instead, ie you are gonna blow the movement if you are not careful

[WMWS]

It is a 500 mA fuse. I did a continuity check on it just to see if it is still good. It seems to be.

[Kirk Ellis]

I have found the easiest way to check the electrical system current is with a DC (DC, not AC) clamp on ammeter. Available from Harbor Freight, Fluke makes them, and several other companies. Might be some at Lowe's and Home Depot also. Just check the package or specs. Nice thing about these is that you don't have to disconnect any wires or worry about blowing the meter fuse. Just need to find enough slack in whatever wire you are trying to measure the current in to get the jaws of the ammeter around it.

These DC clamp on ammeters use a Hall effect or other sensor to measure the magnetic field generated by the current flowing thru the wire. The AC clamp on type uses the jaws as a transformer secondary and only works on AC. Most clamp-on meters that have DC amps capability also have AC measurement of current built in.

I bought three on sale at Harbor Freight a few years ago, and keep one in my Model A's. They were about $49 each on closeout, though not sure they sell them any longer. It also measures AC and DC voltage, ohms and audible continuity. So I also use it to set the points for timing, test the charging and battery condition, test light bulbs, wiring connections and lots more. Can't beat keeping one in the trunk tools for use on the road.

[Mitch]

Welcome Kirk to the VFF! Good info:

[DaWizard]

Hey Kirk Ellis, WELCOME to the VFF!!

Merry Christmas