Topic: Installing solid state Regulator/Rectifier on CB550

[mgilvary]

Here's my situation: I'm trying to replace the stock reg and rect. on my 1975 CB 550 with a single unit I bought on eBay (http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=4594667115&rd=1&sspagename=STRK%3AMEWN%3AIT&rd=1).

Problem is, the wiring diagram that was included with the unit does not match the stock harness. I think I've figured out the rectifier side, but the regulator side has mystified this non-electrically minded rider.

The diagram calls for a BLACK connection going to negative, a RED connection going to positive and an ORANGE connection going to the power side of the ignition switch. I was hoping these connections would simply match the three wires connected to the stock regulator, but those wires are BLACK, WHITE and GREEN.

I've looked at the CB550 wiring diagrams, but I can't tell if these are the same connections the installation diagram is calling for. Is there any easy way for me to tell using a multimeter.

I feel like an idiot, but there's no getting around it: I'm a dumbass when it comes to electrics.

[TwoTired]

The white wire is your field coil.  The regulator applies power to this wire to make the alternator develop output power.  If you don't have a wire from the regulator for this connection, the regulator is made for alternators with perment magnet fields and will not work for your bike.

Three yellows are alternator stator output.  (goes to rectifier)
black and Red are charging system output to charge battery and run bike's electrics.

The orange is power from the ignition (battery) to make the active components in the reg/rect function.

White wire controls alternator output intensity.  The regulator should apply power to this input as system demands vary.

It is possible that the device you bought runs the alternator at maximum all the time and interupts the charging system output for regulation.  If this is the case, then the white wire would be tied to orange.  But, the instructions should be specific about that.
Do the instructions state application to your bike?  Or, are you taking the sellers word for it?

The pic on ebay doesn't show an orange wire, but it does show a white and pink wire.  You sure you got the right one?
Cheers,

[mgilvary]

A friend popped over for a beer and helped me decipher the installation instructions vis a vis the wiring diagram. I'll report back once I've installed it according to what he suggested.

As for the unit, yes, it was sold as being for my 550, as well as some other models. But, yeah, this is coming from an eBay vendor, not a company like Electrex.

Thanks for the response, Two Tired. I'll be sure to crossreference with what my buddy came up with.

M.

[mgilvary]

Okay, I've taken another look at this installation diagram (which I've attached) after reading your post, and I think I almost get it. It does sound like what you suggest, Two Tired -- that the white wire on the bike connects to one of two orange wires on the reg/rec (I had assumed the rectifier harness was a straight connection to the reg/rec, but that does not appear to be the case).

If that's correct, then I think I only have one question: where do I connect the second orange wire? The instructions say "this orange connects to power side of ignition switch," but I don't see any obvious and simple connection for that in the stock harness. Any ideas? I'm assuming that what I need is a connection that only gets power when the key is turned, no?

[TwoTired]

Here is how I would hook it up given the diagram you posted.  Access to all required connections are to the bike's regulator AND rectifier connections.  You wiil have to add male spade terminals to the reg/rect. wires.  Or, splice and solder directly onto those three wires.  You will probably have to sacrifce the connector and wires from the old rectifier, and splice the appropriate wire into that bundle for the new reg/rectifier.  Or, eliminate the lower connector entirely and modify the bike's wire harness (splice and solder) to make the connections from the new reg/rectifier.

Reg Rectifier_/_Honda CB550

Bundle 1 __/__six pin old Rect connector (bottom of pannel)
yellow------------yellow (alternator three phase AC output)
yellow------------yellow (alternator three phase AC output)
yellow------------yellow (alternator three phase AC output)
Bundle 2 __/__six pin old Rect connector (bottom of pannel)
Red   ------------Red/White (Battery plus direct)
Black--------------Green  (Battery return, or ground)

Bundle 1 __/__Old reg connectors
Orange--------- white  ( Alternator Field)
green -----------green  ( Alternator Field Ground)
Bundle 2__/__Old reg connectors
Orange----------black  (Switched battery power)

Cheers,

[mgilvary]

Two Tired, you're a gentleman and a scholar. Thanks for putting together that list. I have one last question. The install diagram shows the fuse between the battery plus and the red lead. You suggest connecting the rectifier red/white to the reg/rec red, but that doesn't appear to be a fused connection. If I pop out the main fuse, I can still get continuity between the red/white wire and the positive battery terminal.

Should I simply connect the reg/rec red lead to the main fuse box?

[TwoTired]

The stock bike is NOT fuse protected between charging system (including rectifier) and battery.

The black wire that powers/enables the reg/rectifier is fused through the main fuse in the fuse panel.

The hand drawn squiggle of a fuse addition (without a specified rating) leaves me in high doubt about application to this particular bike.  But, if you wish to add one, a 30 AMP in line with the bike's red/white wire should be okay.  I recommend a fuse holder with gold flashed contacts for long corrosion free life.  Harder to find, more expensive, but a worthy price for maintenance free, I think.

There's a lot of unknowns about connectivity and function inside the reg/rect. box.  And, many ways of arranging the internals for function.  Basically, I'm taking my best guess about its functionality based on my experience and many years in electronic design.
Did you get an internal schematic?  If I saw that, I could say with certainty whether the additional fuse was necessary.  I suspect not, though.

Cheers,

[dusterdude]

Two Tired, you're a gentleman and a scholar.....with that face,he oughta be.

[mgilvary]

I don't have any inkling what's going on inside the unit. I could probably pester the seller for that info, but I'm going to try to install it according to your advice first, and without a fuse. As for the appropriateness to this bike, he did specify my year/model, but also specified other bikes as well, so there is probably a certain one-size-fits-all approach to its design.

Once I've connected and tested it (no sooner than this weekend) I'll report my results. This guy sells a lot of these things on eBay, so it might be useful info. I picked it up for $50, half the price of others I've seen. Just hope it's not half as good.

Thanks again for your help.

[mgilvary]

Update: I installed the reg/rec this weekend according to your instructions, Two Tired. I haven't had time to take her for a proper test drive, but I started her up and applied the mutlimeter, and everything appears to check out. Thanks for the help. I'm indebted.

[TwoTired]

Update: I started her up and applied the mutlimeter, and everything appears to check out.

I love it when a plan comes together.  Here's to hoping for continued success!  (Klinking of glasses)
Cheers,

[mwohlenhaus]

if nothing else send it my way, and I will get it figured out and let ya know how it works   and if it's worth buying another one.

[mgilvary]

Okay, follow-up question:

I was testing the reg/rec in the light of day (still haven't taken it for a ride) and saw that the upper end of the voltage range goes up to maybe 16 volts (I have a crappy, analog multimeter, so exact figures escape me). The book says the regulator should top out at 14.5. I assume there is a downside to feeding too much voltage into the battery.

If so, then either there's something wrong with the unit or the installation. Any ideas?

[TwoTired]

Where you measure is important, too.
16V at the battery is marginally too high.  At that voltage your battery should being gassing freely (boiling) as it is being overcharged.  If it is not gassing then your meter is suspect.  What is your battery voltage with the bike shut off?

It's bad enough when people lie, when equipment lies, give it the boot and spring $10 for a digital meter at Harbor Freight.

Remember that the regulator makes it's decisions based on what IT sees at it's terminals.  A voltage drop of a volt and a half in the wiring can "tell" it that the battery isn't charged yet.  What is the voltage reading across the black and green wires at the regulator (bike wiring) while the voltage at the battery is reading 16V?

Cheers,

[mgilvary]

I finally had a chance to work on the bike with a new, digital multimeter. The new reg./rec. is definitely juicing the battery too much -- close to 16 volts. The battery is freely boiling at that point.

I reinstalled my old regulator (NOT a stock reg, but an aftermarket solid state reg), leaving the rec/reg connected as a rectifier, and tested it again. It tops out at just over 14.5, which, if I recall correctly, is what it should be doing.

Is there anything I can do to make the new reg./rec. function properly, or am I just hosed?

[TwoTired]

Did you compare the battery terminal voltage with the readings at the black and green wires to the regulator?

Is there any adjustment feature on the reg/ rect?

The only other thing I can think of is to see if there is a different ground potential between the green rectifier ground and the green regulator ground.   Or, the green and black wires of the suspect reg/rect.  If you can measure 1.5 v between them, that would explain the error.
Is there a way to get inside the reg/rect to examine its circuitry?

Good luck!

[mgilvary]

Did you compare the battery terminal voltage with the readings at the black and green wires to the regulator?

It seemed to be the same.

Is there any adjustment feature on the reg/ rect?

Nope.

The only other thing I can think of is to see if there is a different ground potential between the green rectifier ground and the green regulator ground.   Or, the green and black wires of the suspect reg/rect.  If you can measure 1.5 v between them, that would explain the error.

Could you briefly explain how to test for this? Remember, you're talking to someone who thinks electricity is some kid of dark magic.

Is there a way to get inside the reg/rect to examine its circuitry?

Nope. It's sealed up with that solidified gelatinous stuff.

I've contacted the eBay seller (who sells a lot of these), but have not had a response yet.

[TwoTired]

The only other thing I can think of is to see if there is a different ground potential between the green rectifier ground and the green regulator ground.   Or, the green and black wires of the suspect reg/rect.  If you can measure 1.5 v between them, that would explain the error.

Could you briefly explain how to test for this? Remember, you're talking to someone who thinks electricity is some kid of dark magic.

I'm clutching at straws here.  What I am trying to verify, is the ground referenced at the rectifier portion is at the same potential as the ground used by the regulator portion.  If there is a voltage offset between them of 1.5 v, it might transfer as a voltage delivery error.  This can happen if the internal reg/rect circuitry is is not interconnected properly, and the bike has a wiring error.  Low probability, but just trying to cover all bases.

It's an easy check. Place the minus probe on one green wire and the plus probe on the other green wire.  Measure voltage offset.  Should be zero.  If not  - problem identified.

At this point, it seems likely that the unit is faulty, the wiring diagram given is wrong, or

Best of luck!