Rec reg Lithium bettery

Wilas89

XS650 Enthusiast
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Hi
Dose anyone of experience with RR35 Rec Reg from electrex world?
https://www.electrexworld.co.uk/acatalog/RR35.html

I bought one from my 72 XS without seeing the warning on there website saying not for use with a Lithium battery . I have a Skyrich bettery (HJTZ5S-FP-SWI)

From the limited info I have on the rec/reg it looks fine as the TYP charge voltage of 14.5v. My battery needs 14-15v

Dose anyone run the same setup?

Thanks for any help
Will
Cornwall UK
 
I have read a lot of that post. Doesn’t seem to answer my question but is interesting reading.
Thanks
 
Been doing lots O reading on lithium. The linked thread in the past above covers lots of typical scenarios, IMHO your possible gotcha is the battery you bought does not appear to have self balancing electronics. I'm pretty sure that's a must have for long life... But if you see NO MORE THAN 14ish AT THE BATTERY terminals you'll prolly be fine. An occasional shore charge with a "better" designed for lithium charger would be cheap insurance.

Edited to correct an erroneous statement of voltage. 1/12/19
 
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What I’m not sure about is why the manufacturer of the rec reg would say it’s not suitable for Li ion. From my reading mosfet should be ok ?
 
I'm guessing mainly because they also sell one specifically for lithiums.
That site drives me nuts they don't show wiring diagrams for any of the regulators, grr.......
 
Very interesting, I found this quite informative regarding voltage limits. I have been looking into MOSFET regulators recently and there are just so many fakes out there. The fakes are now looking exaclty like the Shindengin regulators with same casting marks and stainless steel back plate. The big give away is the price. Genuines are typicaly up around £100.

Note: I stumbled across the following DIY MOSFET regulator project which regulates at about 14V so may be of interest to those who want to experiment with Lithium battaries. The voltage output is easily increased by inserting a higher Zener than that used in this project if the PMA folk are interested.

https://www.instructables.com/id/How-to-make-a-reliable-motorcycle-voltage-regulato/

Perhaps someone can suggest a better thread to add this PMA information to?
 
I need to keep digging, but I think a lithium battery with a BMS (battery management system) will exist just fine without a "lithium specific" regulator. We are still in the (late, early) period of widespread lithium use in motorcycles. So there is a lot of misleading info and half truths floating around. Since size and weight savings are so attractive they will end up dominating the motorcycle custom and aftermarket.

Some poop on lead acid vs lithium chargers; http://www.enerdrive.com.au/can-charge-lithium-battery-lead-acid-charger/ The quick takeway is; do NOT leave a lithium sitting on a lead acid "maintenance" charger!
It conveniently bypasses the BMS equipped or not issue. I'm off to battery university see what they have to say.
 
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Hopefully I will get some good information back from skyrich as I have no real idea what set up they are using. I wish companies would give better data sheets on their products, would make this a lot easier.

I am considering adding a switch to isolate the charging system so the bike runs at a total loss, if I sense there is a problem. Not sure, might be a waste of time?
 
Nearly all mosfet regulators are for PMA alternators, won't work with the stock field type alternator.
Anyone know of a field controlling mosfet regulator by all means pipe up!
 
Nearly all mosfet regulators are for PMA alternators, won't work with the stock field type alternator.
Anyone know of a field controlling mosfet regulator by all means pipe up!

I thought mine is for field type alternator, or dose it just fully excite the field and regulate the result?
 
I thought mine is for field type alternator, or dose it just fully excite the field and regulate the result?
Seriously; I'm like a butterfly flitting here and there.
yes that one does appear to be mosfet AND for a field type alternator.
For sure a visible to the rider, calibrated voltmeter is a good thing to keep an eye on. Would like to hear reports of what you see with that setup..
 
Waiting for my tank to get back from the painters and I also need to finish marking alamuinum box for electrics before I can test it out . Will let you know in a few weeks .
 
Maybe I could help to clarify.
Or make it worse.

With the PMA charging systems, the argument is MOSFET vs SCR.

The SCR design shunts (dumps) excess current to ground, back thru the PMA windings, creating heat.

The MOSFET design blocks excess current, producing less heat, but induces high voltages in the blocked PMA windings, challenging their dielectric coatings.


For our XS650s, with the field excited regulator, regulating the current of the rotor, the argument is usually Mechanical type B (relay-type) vs Solid-State type A.

The Mechanical (relay) type uses contacts that can get dirty or burned, and flitters between 3 power states (full, partial, grounded) which produces erratic voltages. This is the type B regulator that supplies power to the rotor on the 70-79 bikes.

The Solid-State type has no contacts and produces a much smoother output. This is the type A regulator that supplies a regulated ground to a powered rotor on the 80-84 bikes.

Now, for the variances.

You *can* find and use a Solid-State type B regulator to power the rotor on the 70-79 bikes.

You *can* reconfigure the early type B brush block to the later type A, and use a later Solid-State type A regulator. See the "3 nylon screw" mod.

Both type A and type B regulators can be packaged with a 3-phase rectifier, making a singular rec/reg unit. Normally a 7-wire device.


Now, with respect to the MOSFET labeling on the ElectrexWorld RR35 rec/reg.

Traditional Solid-State regulators use good ol' silicon transistors that reference a zener diode voltage to produce internal currents that are 'current gained' to control the output current of the rotor. The design risk is in using a batch of transistors that have varying hFE (gain).

A MOSFET regulator would use Field-Effect transistors that reference a zener diode voltage to produce internal voltages that are 'current gained' to control the output current of the rotor. This subtle difference would use less internal current, and run cooler. A bit risky back in the '80s, since MOSFETs were sensitive to moisture, spurious voltages, and static. Modern MOSFETs built to industrial/automotive specs (vs consumer grade) usually don't have that problem.

So, in summary, a MOSFET regulator for an excited field (rotor) type alternator could have a slight edge over the older transistor design. I personally feel that the MOSFET labeling in this particular instance is to capitalize on the marketing hoopla...
 
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