Ex-500.com - The home of the Kawasaki EX500 / Ninja 500R banner
1 - 8 of 8 Posts

Registered
Joined
83 Posts
Discussion Starter · #1 ·
Every once in a while it becomes obvious I haven't done a good enough job explaining myself, I will say I am an induction specialist (the closest thing I know of to an expert).

So the only accurate way to test a stater in place using permanent magnets is using a rotating magnetic field at a fixed RPM and measuring open circuit voltage phase to phase. FYI OEM is Delta connected, ungrounded aftermarket is generally Y connected ungrounded. The reason why you can't accurately measure or test is, the full magnetic field is present even at rest/standstill.

The only accurate way to test a stator on the bench is using a LCR meter, not a ohmmeter.

So why a LCR meter, take the number of turns per pole 44 times 6 = 264 turns,Stator Rewinding

divide that into the manual spec resistance of 0.18-0.27 ohms which = .000681 to .0010 ohms per turn, lets go out on a limb and say one pole is completely shorted 0.27 divided by 6=0.045 ohms, let me tell you your leads average 0.25 to 0.50 ohms, so even if you know how to zero your leads, we are talking 0.027 minus 0.045 =0.22 ohms .

Using my method at a fixed RPM will detect even 1 shorted turn, or 1/264 of the effective impedance of the winding, your choice , follow the manual or follow my test method.BTW I don't own anything that will measure 0.045 ohms in place on a inductive load.
Simple explanation : using the open circuit 2000 RPM test--all readings should be within 0.5 volts AC and within 22 to 30 VAC, other-words, you measured A-B =22VAC, B-C =22.5 VAC and C-A =21.5 VAC would indicate stater is good




Simple explanation : using the open circuit 2000 RPM test--all readings should be within 0.5 volts AC and within 22 to 30 VAC, other-words, you measured A-B =22VAC, B-C =22.5 VAC and C-A =21.5 VAC would indicate stater is good

Same test method---A-B = 16 VAC , B-C = 4 VAC, C-A = 2 VAC == Your stater is toast

Same test method --A-B==26 VAC, B-C = 16 VAC , C-A = 19 VAC ==Your stater is toast




BTW reference previously about a grounded stator, except for measuring VAC while running, any pole to ground will measure to ground on all three phases. A little trivia, the Versys stater has 3 phase delta wound, each phase has six poles= a total of 18 poles with 44 turns of 18 gauge magnet wire.
 

Registered
Joined
83 Posts
Discussion Starter · #2 ·
Amp Hour 101 Versys 650

Battery is 10 amp hour, if new roughly 130 watt hours ( 12.9 VDC rounded up X 10 amp hour) or 130 X 60 minutes X 70% divided by 100 = 5460 watt minutes , since base load including headlight is 170 watts, not taking into consideration the starting watts required, would be 5460 divided by 170 = 32 minutes, or a days walk from home.

Note: ( 70% is a figure used because unlike lithium ion, glass mat or lead acid, will drop in voltage as it is discharged, so roughly 7 to 8 volts is when things start shutting down, ECU has it's own voltage regulator, ignition and injectors , fuel pump will not function very well at the lower voltage)
 

Registered
Joined
2,983 Posts
Total loss ignition racers know how long a battery will last. If the flat top of the tank was covered with high efficiency solar cells, would it charge enough while at work to get you home? Or, are there EV charging stations there?
 

Registered
Joined
50 Posts
"FYI OEM is Delta connected, ungrounded aftermarket is generally Y connected ungrounded."

Um, what? Are EX500 stators delta? Every stator on a motorcycle I have is Wye. Not saying yours isn't delta...

"Simple explanation : using the open circuit 2000 RPM test--all readings should be within 0.5 volts AC and within 22 to 30 VAC, other-words, you measured A-B =22VAC, B-C =22.5 VAC and C-A =21.5 VAC would indicate stater is good"
Not according to the shop manual.
The Ninja 500 /GPZ500S shop manual wants 56VAC at 4000 rpm. The wiring diagram shows a Y diagram. I suspect they are Y, not Delta. Not trying to troll you, but I think you should be careful. Someone might read this and wonder why their bike doesn't conform.
 

Registered
Joined
83 Posts
Discussion Starter · #5 ·
"FYI OEM is Delta connected, ungrounded aftermarket is generally Y connected ungrounded."

Um, what? Are EX500 stators delta? Every stator on a motorcycle I have is Wye. Not saying yours isn't delta...

"Simple explanation : using the open circuit 2000 RPM test--all readings should be within 0.5 volts AC and within 22 to 30 VAC, other-words, you measured A-B =22VAC, B-C =22.5 VAC and C-A =21.5 VAC would indicate stater is good"
Not according to the shop manual.
The Ninja 500 /GPZ500S shop manual wants 56VAC at 4000 rpm. The wiring diagram shows a Y diagram. I suspect they are Y, not Delta. Not trying to troll you, but I think you should be careful. Someone might read this and wonder why their bike doesn't conform.
I am asking a favour, could you take a photo of that stator wiring diagram, and a FYI, I have a old failed stator and was planning to rewind it from Delta to Y connected, several advantages, some disadvantages. For a Y connected equivalent of my Versys or KLR or Ninja 650, the wire gauge is 18 gauge for the Delta, I would need to use 15 gauge to wind star, on the advantage side, less turns which equals more room as the coating is 0.003 of a inch. So I need to look up my post but something like 15 turns per pole less , so 15 times 0.003 of a inch. I also looked at dropping a couple turns. If you understand the principle of induction, a transformer rated at 100 VA at 100 volts say 1000 turns would have 100 turns on the secondary at 10 VAC and 10 amp. The primary would be 1 Amp AC.
So having a ratio of turns to magnetic field strenght exceeding what you actually need reduces the available current.

Anyway a photo of that stator and any related info would be fantastic.
 

Registered
Joined
83 Posts
Discussion Starter · #7 ·
Awesome.

Again, note the regulator connection goes to the load and the load side of the battery 30 amp fuse.


Y or Star connected. Since the drawing is there. Not today but I will add to this. First a little explanation for any electrical guys involved in big industry. So 30 to 40m years ago there were many different starters for large horsepower motors. generally anything over 50 Hp with High torque rating. Star Delta starters. There was what is called open transition and closed transition, unless somebody asks not going there. So it would start as a Y connected motor and after a preset time, possibly 6 to 10 seconds it would change to Delta Connected Star Delta Starter: What is it? (Working Principle & Circuit Diagram) | Electrical4U

So Y connected, the phase current and line current are the same value. The line voltage is 1.73 times the phase voltage. One advantage is less turns are required . One disadvantage is the wire size in my previous example of being 18 gauge Delta would be 15 gauge Y connected, it is much harder to wind with a heavier gauge wire.

One disadvantage with Delta-and this is the first time I have seen ANY Kawasaki stator Y connected-is if you have a shorted turn say within the phase A to B , B to C and C to A will compound that short. In a Y connected shorted turn, you will have a drop in voltage on the A to B phase but because the line voltage is 1,73 times that of the phase voltage it is less noticeable.
As to shorted turns, my test remains the very best way. Resistance measurement is a waste of time, few have what is called a low R meter. bench testing, best to use a LCR meter.
So sometime this week i will post the winding dope for a KLR or Versys 650 Stator, along with a conversion to Y connected. The wire gauge, the total length of magnet wire needed, and possibly some photos of rewinding a stator by hand.
If there is interest, I don't mind answering questions- on anything electrical.
 

Registered
Joined
50 Posts
Total loss ignition racers know how long a battery will last. If the flat top of the tank was covered with high efficiency solar cells, would it charge enough while at work to get you home? Or, are there EV charging stations there?
solarwise, No.
You could get maybe get about 12-15 watts of cells onto a tank, ( near an amp output) get a full charge in full sun after 10 -12 hours**(very simplistic and assumes your battery is DEAD FLAT and is the normal 10-14ah capacity as most MC batteries are, ) and then get about as far as you would if your stator had suddenly quit. Whereby, you'd sit at the roadside and wait until your battery recharged again.

This'd be really hard on the battery . So, no, or at tleast, not practically unless you live very close and it was convenient to
twiddle your thumbs for long periods.

BUT if you wanted to get a streamlined array to cover bike and rider, gee! -you might not need a stator at all! :)
 
1 - 8 of 8 Posts
Top