Can a battery be recharged still connected on our older Guzzi?

[p6x]

Just a little bit of context; when I got my first car, I was told to never recharge the battery while still connected; else I would damage the alternator.

As I am mainly using my Quota during the colder days here in Houston, I want to keep the Odissey on my V11 charged. However, removing and reinstalling the connctions is cumbersome as there is very little space.

I am asking as an abundance of precaution, because when you install tender connections on your battery, you are in a similar configuration.

 

[po18guy]

As long as the connections are directly to the battery terminals, the current flows via the shortest path, which is through the battery. Any current flow or drain would receive battery voltage in any case. However, it would be nice to have a master battery disconnect as installed on classic cars, to isolate the system and prevent any potential drain while parked. 

[p6x]

25 minutes ago, po18guy said:

As long as the connections are directly to the battery terminals, the current flows via the shortest path, which is through the battery. Any current flow or drain would receive battery voltage in any case. However, it would be nice to have a master battery disconnect as installed on classic cars, to isolate the system and prevent any potential drain while parked. 

Thanks!

[docc]

There has been some extensive discussion of this matter here. At one time, there was an opinion from one of the regulator/rectifier suppliers to disconnect the battery when charging from an external source.

Subsequent discussion from some knowledgeable members refuted this based upon the presence of diodes in the regulator/rectifier stating that it is fine to charge the battery without disconnecting.

Since I have a "service switch" as part of the 30 amp circuit breaker set-up, I always disconnect when charging because 1) it's easy for me, and 2) isn't it the diodes that are at risk of damage in the R/R to begin with?

[docc]

Some excellent commentary from @MartyNZ in this thread, along with emphasis on using the correct charger . . .

 

[Lucky Phil]

49 minutes ago, p6x said:

Just a little bit of context; when I got my first car, I was told to never recharge the battery while still connected; else I would damage the alternator.

As I am mainly using my Quota during the colder days here in Houston, I want to keep the Odissey on my V11 charged. However, removing and reinstalling the connections is cumbersome as there is very little space.

I am asking as an abundance of precaution, because when you install tender connections on your battery, you are in a similar configuration.

 

This makes zero sense at all as probably over 2 billion vehicles worldwide are at some point on battery tenders/chargers with the batteries still connected. When you come across stuff like this you look at the overwhelming evidence in front of you and see if it aligns with the "advice" you've been given.  

Phil

[Lucky Phil]

16 minutes ago, docc said:

There has been some extensive discussion of this matter here. At one time, there was an opinion from one of the regulator/rectifier suppliers to disconnect the battery when charging from an external source.

Subsequent discussion from some knowledgeable members refuted this based upon the presence of diodes in the regulator/rectifier stating that it is fine to charge the battery without disconnecting.

Since I have a "service switch" as part of the 30 amp circuit breaker set-up, I always disconnect when charging because 1) it's easy for me, and 2) isn't it the diodes that are at risk of damage in the R/R to begin with?

That warning docc is you're manufacturers typical "get out of jail free" warning. Who in their right mind is going to disconnect the battery when on a charger or even more ludicrously when they need to jump start a vehicle. What, disconnect the reg then jump start and with the engine running reconnect the reg?

Phil

Edited 23 hours ago by Lucky Phil

[po18guy]

Isn't the R/R isolated when the ignition is off? We are dealing with Mandello electrics, so at some level, all bets are off.

Edited 23 hours ago by po18guy

[docc]

7 minutes ago, po18guy said:

Isn't the R/R isolated when the ignition is off? We are dealing with Mandello electrics, so at some level, all bets are off.

The charging wire to the battery positive from the regulator, through our nefarious 30 amp Fuse #3, is continuous and not switched. Neither is the grounding side switched, not the weedy factory ground through the harness nor any (recommended) additional ground from the regulator case to the timing chest/engine.

[po18guy]

So spinning the engine key off will charge the batt?

[docc]

Just now, po18guy said:

So spinning the engine key off will charge the batt?

Unlikely, as the R/R requires a voltage reference to function and that is switched through Relay #2.

[po18guy]

It's all one big happy Italian family!

[docc]

Here is the Kiwi_Roy diagram of the R/R. If one applies current to the red wire, from the battery side aka external charging, and the regulator is grounded, will that current "do" anything inside the regulator or simply not cross diodes 4 and 5? Could those (or the other) diodes get damaged applying that current backward into the R/R?

@MartyNZ had stated that a problem might be related to the charging pulses from charges that use a "desulfation" mode . . .

[MartyNZ]

8 hours ago, docc said:

Here is the Kiwi_Roy diagram of the R/R. If one applies current to the red wire, from the battery side aka external charging, and the regulator is grounded, will that current "do" anything inside the regulator or simply not cross diodes 4 and 5? Could those (or the other) diodes get damaged applying that current backward into the R/R? @MartyNZ had stated that a problem might be related to the charging pulses from charges that use a "desulfation" mode . . .

 

Diodes 4 & 5 block reverse current flowing to the regulator, so unless the charger exceeds 200 volts, I see no reason to disconnect the battery during charging the battery while connected. I do it all the time.

There is a situation where jump starting can damage a regulator of an alternator which has variable field current, like most cars. The supply vehicle regulator can see a low voltage since the connection to the flat battery causes the entire system voltage to go low. The suppling regulator raises output of the supply alternator armature current. If the jumper cables are disconnected in ths situation, then for a very short instance, the alternator output voltage spikes as the armature current settles down to a normal value. That momentary spike can damage the solid-state components in the supply vehicle regulator. The damage is at a microscopic level, and takes several weeks before the regulator totally fails. Since the V11 is disconnected at the instant of the spike, and has a permanent magnet armature, the V11 regulator cannot be harmed by jump starting.

So charging a connected battery with the appropriate charger cannot harm the regulator.

Jump starting can harm the V11 battery (not the regulator) if you directly connect a large 12v battery directly to the bike with heavy current cables. It is possible to exceed 150 amps charging, which can damage the bike battery. 

Edited 14 hours ago by MartyNZ

[po18guy]

I "thought" that diodes carried that protective capacity. I used a car battery with 6 ga. fine strand oxygen-free (blah blah blah) speaker wire to jump the old V11 and did not worry about the battery, as it is shot anyway. 

I specifically made the jumpers out of speaker wire and it turns out that they flow a LOT of juice.