With my volt meter set on AC Volts, and touching the 2 wires from the dynamo, I am getting a readout of 16.6 at wide open throttle, and 11.2 at idle. Am I correct in thinking that I need a new dynamo?
What part of these numbers suggest to you that your dynamo is failing? I assume you know that most electrical systems do not have the ability to charge the battery at idle speed.With my volt meter set on AC Volts, and touching the 2 wires from the dynamo, I am getting a readout of 16.6 at wide open throttle, and 11.2 at idle. Am I correct in thinking that I need a new dynamo?
16.6 AC is low - what tractor is this on? Not that it really matters, but typical AC output BEFORE the rectifier is higher than that.With my volt meter set on AC Volts, and touching the 2 wires from the dynamo, I am getting a readout of 16.6 at wide open throttle, and 11.2 at idle. Am I correct in thinking that I need a new dynamo?
Here is what I have today.
Belt is tight, grounds are cleaned and reconnected. Battery cables removed, cleaned and connected
1) Battery volts before cold start up.... 13.2 V
2) I started it and let it run wide open for 5 minutes....Volts at battery were then 14.83
3) After 15 minutes of wide open running, the AMP (Battery) light came on. Volts at battery reading 15.73
4) I engaged the PTO, the volt reading at the battery is reading 16.03, the AMP light stays on
5) I turn the headlights on, along with the PTO, the battery volt reading is 13.50, the AMP light still stays on
6) After running for nearly 20 minutes at wide open, the AMP light stays on. I then turned the engine off and read the battery volts at 13.17
Now I'm thinking voltage regulator. What's your diagnosis?
Please start a separate discussion regarding this TOTALLY DIFFERENT problem from what this discussion is about. (I know the answer to your question but this needs to happen in new discussion.)Sorry for tgging on to someone elses thread but in reading this I ask ; would a bad ground cause their to be ZERO power to the key switch?
the idea is correct but it's not the regulator that does it, it's the rectifier. It "rectifies" the dynamo's ac voltage to dc voltage that charges the battery. The rectifier is built into the regulator "box", technically called a regulator rectifer, but we shorten it to "regulator" because it's easier to say it.Think of the AC wave. It is a solid up and down wave. The voltage regulator takes the up and down (basically) so if 14.5 VDC is desired needs at least 29VAC.
Ya, but most parts guys only know the regulator part. Wrenched on mowers and cars for years. Mowers and older cars typically much the same setup.the idea is correct but it's not the regulator that does it, it's the rectifier. It "rectifies" the dynamo's ac voltage to dc voltage that charges the battery. The rectifier is built into the regulator "box", technically called a regulator rectifer, but we shorten it to "regulator" because it's easier to say it.
also depending on which type rectifier is used, the ac voltage may not be cut completely in half, but if we think that way, it will get us in the right ballpark. Most Kubota's with external reg/rec use bridge rectifiers which mostly cut ac volt from the generator in half, but the frequency of current may be higher than with a simple half-wave rectifier.
I wish I knew more about electronics and how their hardware does what it does. It's getting too late for me to get studied up on it though
Whoa! I always thought you were younger...already turned 90?I wish I knew more about electronics and how their hardware does what it does. It's getting too late for me to get studied up on it though