Hello, John Talley here with Partzilla.com. Today we're going to spend
a little bit of time talking about the voltage regulator rectifier that's found
on just about every machine in the power sports industry whether it be a ATV a
side-by-side or a motorcycle. I'm going to walk you through the process of how
to test it and how they're put together the way you have a better understanding
of what's going on inside here. The only special tools you're going to need? Pick
up a good digital voltmeter. Make sure that it has this little signal right
here which shows a diode test. Now if you don't have one, we actually carry one on
Partzilla.com you can pick up. So, once you have your
regulator rectifier out on a bench and a good volt/OHM meter we can show you how to
get it tested. So let's go.
So if you're watching this video, chances are your machine is not charging. Now if
you've already eliminated the possibility of a bad battery and your
stators are giving a good output-- we have a video on that by the way-- well, chances
are it could be your regulator rectifier. Because what this thing does is take
that AC signal that your stator is developing and converts it into a DC
signal that is used to charge your battery and provide power for whatever
load that you may be using on your machine. Usually in between 12.8 all the
way up to fourteen point one two three depending on what type of battery's in
the machine. The way it does that is what they call a full wave rectification. So
what you have there is an AC voltage which is a sine wave that goes from
positive to negative through a certain amount of time. And what it is doing is
taking that, flipping that bottom half to where you've got a continuous positive
AC hump and then that's using what they call a smoothing capacitor to keep it
charged in between positive and negative swings. That is what eventually comes out
through your positive and negative and goes to your battery and provides charge
to your machine. So, with that a little bit of background do you really need to
know all the electrical engineering behind it? No, there's a simple way to
test those six diodes to see if they're working or not. A diode basically is an
on/off switch for current. If you forward bias it, it lets current pass through. If
you reverse bias it, it acts like an off switch. It does not let current flow. So
what we want to do is go in and test each one of those to see if it's forward
biasing and then reverse bias it and make sure that it's stopping the flow of
electricity. So, if we're going to look at three different types. We're gonna look
at one from Yamaha, one from Honda, and then we're gonna finish up with this
unit from Polaris. And all these may look the same on the outside, how they work on
the inside is going to be quite different as you'll find out. There's
certain ones that we can test, and spoiler alert: there's certain ones that
we cannot so you may want to watch this all the way through to find out what I'm
talking about. So, let's look at what's going on inside of your typical
regulator rectifier. What you basically have here is the
stator. That gives your AC voltage and current that is sent into your regulator
rectifier. There are two separate parts of the regulator rectifier as the name
suggests You've got a section of diodes that actually takes the AC waveform,
inverts it and then used with a capacitor gives you kind of a saw-edge
output of DC voltage. The other part of that is actual regulator. What the
regulator does is, well, regulates the voltage. Well, using the Volt/ohm meter set
two diode you can actually forward bias these six diodes and that will tell you
if the rectifier portion of the circuit is operational or not. What you should
read on a typical silicone based diode is around point four eight to point five
two volts. So let's take a look at Honda. This is going to be the positive
terminal, this can be the negative terminal. So to forward bias, we want to
put our negative lead on the positive side, and then take our positive lead
over to each point on the rectifier itself. And we should see 0.5. And we do.
Alright that's telling me that we forward biased each one of those diodes.
Now what we need to check is to make sure that it's going to stop current
from flowing in the wrong direction. So we're going to reverse it. We're gonna
put our positive where the battery would be, and then we're gonna reverse bias it
by putting the negative here. Open, open, open.
So those three you're doing what they're supposed to do. Now, let's go over to the
other set of diodes. Now this time we're forward biasing them again, so it should
let current go through. Point five, point five, point five. Now, if we try to reverse
those same three diodes we should have an open on each condition. Open, open,
open. And that's how we test this one. Each one of them I was able to forward
bias it. Now let's take a look at the Yamaha. These three connections if they
were plugged in, would be going over to your stator-- a three-phase stator winding.
Your output, this is going to be positive side and this is going to be the
negative side. And if you look on your machine I believe this is red this one's
black. We're gonna take the positive lead and go to the negative side, then we're
going to take the negative lead and go to each point here and that should
forward bias it. Point four nine, point five one, point four nine nine. So what I
just did it forward biased each one of those diodes. Now, we take our negative
lead off the volt/ohm meter. Put it to the positive side of the regulator rectifier
terminal and then we'll go to our three points which would forward bias
each one of these diodes. Now how did that change? Should be some diodes there, right?
Well, actually they are there. The trick is well, there's other
circuitry that you can't measure from outside. Let's refer to the next drawing.
Alright, as before those are our six diodes that we're trying to test. There's
a regulator rectifier and you've got these three looks like SCR type diodes
there. What would they be doing? Well, a regulator limits how much current or
voltage is coming out by actually shunting out each one of these legs to
ground. So now positive here forward biasing back had no problem. It was going
against that gate so we were only reading those three diodes. When we were
going the other direction, we were actually paralleling a forward bias
diode here in whatever circuitry they were using inside of the regulator on
the other side. So it's easy to go in and read the forward bias across each one of
these diodes, but guess what? When you try to forward
bias these you're also trying to forward bias these different transistors down here so
it's going to give you a different reading other than the point five. Let's
go one step further. Let's look at the Polaris. This would be the plug that goes
to your stator. This will be the plug that actually goes
to the vehicle electrical system. That's going to be your positive. This is gonna
be your negative. So let's take our meter, let's put it to the negative side and
see what kind of readings we get. 0.5 we're expecting that. 0.5, 0.5. Okay. It's
looking about like the Yamaha was. Let's go to our negative side. Nothing, nothing,
nothing there either. So what in the world is going on with the Polaris? Are
you telling me that this is only a half wave rectifier? I kind of doubt that.
Let's look at this next drawing. Well, is this the circuit that I'm sure is inside
this particular unit? No I can't tell you that. But I think I can explain what's
going on. Once again it was very easy to forward bias these three diodes going
back to the battery. Now look what happens when you try to forward bias
these back from ground. Well guess what? You're running into a whole network of
the regulator that's actually telling it what to do as far as the voltage. So is
there any possible way you can take a diode test voltmeter and test through a
MOSFET circuit as well as a voltage bridge and then an op-amp down at the
bottom? It simply can't do it so that's why it was giving you an open circuit
trying to read that direction. Once again I wasn't in on that design meeting so I
don't think Polaris is going to tell me. So what do we learn from all this? Well,
depending on the manufacturer, yes you could test some of the aspects may be
all six of the diodes that are part of the rectifier circuit. Other times you
start running into the regulator side that's going to prevent you from seeing
both sides of the rectifier circuit. Especially with this one it's
not giving you any clear indication of what's going on inside of it.
Well it's process of elimination here guys.
There's no way to properly test every single regulator rectifier out there
using just a voltmeter. It just can't be done. There's too many variables. So what
do you do? Well first you make sure your battery is in good shape. Second, make
sure the cabling on the machine is up to snuff. No shorts, no opens. If you can, do a
dynamic test on the stator to make sure you're getting the appropriate AC signal
sent to the regulator rectifier. And if all of that checks out, well whatever's
left must be the problem. It's gonna be your voltage regulator rectifier. A
couple of things that are going to signify that either it's not charging at
all or is overcharging and destroying your battery. So we are here to help if
you need help, get in touch with us talk to us we can try to steer you in the
right direction to figure out the problem on your machine. Once you've
figured out that problem, come see us at Partzilla.com where we have all the OEM
parts from all the different major manufacturers ready to go and can get
them to you quickly. Listen we just want to say thanks for shopping here with us
at Partzilla.com and we will see you in the next video. Oh, if you like what you
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I'm working on next. Y'all have a great day.