Parasitic Draw or Electric Lamprey

[Halloweenie]

The old battery that was in the bike when I bought it died on me on Wednesday and I had to get a tow home. Thankfully I had seen this coming (my float charger alerted me that something was funny), and I had already ordered a 12 Cell Ballistic battery, which of course arrived just after I left.

So when I went to install the new battery I wanted to make sure everything was hunky-dory. While checking I found a small parasitic draw and I went about tracking it down. I found it fairly quickly, the rectifier/regulator wires gong to the battery, but I didn't understand how that could be (the rectifier I have is from my HHB PMA kit). I went through all of my electrical connections and repaired any that looked funky and cleaned every contact I could find. Yet, no matter what I tried, I still had the same parasitic draw with the rectifier/regulator attached. Only when I disconnected it did the parasitic draw drop to zero.

This is probably stupid because it is such an insignificant amount, but would a .03 mA parasitic draw from the rectifier/regulator be abnormal? Should I be planning to replace it? Thanks for the help guys and gals.

 

[jayel]

it's quite possible for a good enough (sensitive) meter to read a small voltage drop acrossed a reg/rec but voltage isn't really the problem, Current (Amperage) is, as you note the current draw is in the Milli amp range and that is what will drain a battery whether the .03 mA is normal or not you will need info from HHB and/or other owners

 

[xjwmx]

I wouldn't think about it, if you don't mean with the key off. Assuming the bike runs right. .00003 Amps is approximately nothing.

 

[sseres]

Mynok from the asteroid in Empire Strikes Back

 

[Halloweenie]

I wouldn't think about it, if you mean with the key on. Assuming the bike runs right. .00003 Amps is approximately nothing.

Nope, parasitic draw is with key off. Think of the alarm on a car; it is draining energy from the battery when the engine/key is off, like a lamprey on a trout.

I do agree as to the insignificance of .03 mA, I was wondering if it is a common ailment of a rectifier.

 

[xjwmx]

^The key should cut power to everything. The only thing that would have power with the key off is one side of the starter relay. So, you have a problem with your wiring or your switch that you should fix. Or a problem with your meter. Measure voltage instead of current. If you see 0V where you were measuring before, then it's just some artifact from your meter. If you used graphite lube in your key switch it could cause this. Graphite is recommended for locks, but not lock switches

 

[pamcopete]

It is common practice for the rectifier to be directly connected to the battery, relying on the diodes to prevent current flow from the battery through the rectifier diodes to the windings of the stator. The difference with a combined rectifier / regulator is that the sense wire from the regulator should be run through the key switch because it is most likely the regulator and not the rectifier that is drawing that small current. However, not all rect / reg combos have a separate sense wire.

The draw of .03mA would discharge a 14AH battery in about 14/.00003 = 466,666 hrs. or roughly 19,444 days or 53 years, so I don't think it is a problem. Discharge meaning that the battery voltage would be 10.5 Volts in 53 years, so you probably could still start the engine.

 

[Halloweenie]

^The key should cut power to everything. The only thing that would have power with the key off is one side of the starter relay. So, you have a problem with your wiring or your switch that you should fix. Or a problem with your meter. Measure voltage instead of current. If you see 0V where you were measuring before, then it's just some artifact from your meter. If you used graphite lube in your key switch it could cause this. Graphite is recommended for locks, but not lock switches

My meter is good. It's showing 2.5 Volts, and it is only on the leads directly from the regulator to the battery, no other connections to the battery. If I am correct, the regulator is directly connected to the HHB PMA, and then to the two battery terminals. The connections are good, just one on each of the wires to the battery from the regulator.

 

[xjwmx]

^I don't know how your PMA ETC is wired, so I can't be much help really. Pete says it's common practice to wire what you have before the switch. The current might be leakage through the diodes he mentioned.

2.5 volts somewhere with the key off is surprising though.

 

[Halloweenie]

The draw of .03mA would discharge a 14AH battery in about 14/.00003 = 466,666 hrs. or roughly 19,444 days or 53 years, so I don't think it is a problem. Discharge meaning that the battery voltage would be 10.5 Volts in 53 years, so you probably could still start the engine.

Excellent, thank you very much! That's what I was thinking, I ride at least twice a week so I figured .03 mA wouldn't be too much of a problem. I love when I don't have to spend energy or money to fix something. I am also grateful knowing that I didn't screw something up. Thank you so much Pamcopete!

 

[rusty rocket]

Not to hijack your thread but do you have any video of some banjo brawling??????

 

[Halloweenie]

To most people, just playing a banjo within earshot can be considered assault. I'll see if I can get some footage of a more physical sort, although that may be impossible now. Here's me a couple of years ago.

 

[xjwmx]

^I've thought about getting a cheap banjo and learning clawhammer style from Youtube. I like the idea because clawhammer sounds more complicated than it is, and because everybody plays guitar. I think I could get it down in a week or two.

 

[Halloweenie]

I play frailing/clawhammer/drop thumbing. I was taught by a Mummer when I was about 15 years old and it is fairly common in Pennsylvania. It isn't as easy as bluegrass, it isn't something you can get down in a couple weeks. I play about a dozen instruments, and the banjo was the second hardest to become proficient at. When you do get proficient though, you can start having fun. I remember one antique show I went to (always bring a banjo to these things), there were about a dozen banjo players and we all sat down and started playing together. We drew quite a crowd, you don't see that with guitars. The banjo is a unique sound and even if they think it is funny, people will stop and listen to a banjo.

As for a cheap banjo, the Deering Goodtime five-string is a gosh darn good starter banjo. It's not the best but it is a good solid quality instrument. You might be able to find one for about $400 if your lucky. If you're looking for a used banjo, (nothing against them, I traded a cello for mine which was old when I got it) check Craigslist, and look for wear on the head like mine. It is telltale sign of a frailer, which is played at the top of the pot, whereas finger picking is played at the bridge. The big wear spot is from the thumb sliding and hitting the 5th string.