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Strange alt issues

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rtrinkle
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Strange alt issues

thought someone might be able to shed some light on an alternator issue. 

Have a Motorola 55 amp directly connected to 2 paralleled 198 amp hour AGM batteries. Batteries were at 60%. Ran engine for about 6 hours on a calm day. Got back to dock, batteries still at 60%. Put on charger, batts fully charged in 2 hours.   Strange ting, batt monitor and gauge showed 13.5 volts, or somewhere around there. Don't understand why batts did not charge. Can anyone shed some light?

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

LeslieTroyer
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You might have a lot of voltage drop between the battery and the alternator.  Or your alternator may be getting hot and lowering its output.  Or The voltage regulator might be set too low. I'm sure there may be more but I would check that first.  

When I was looking at how to extend the life of my AGMs one of the key things was the voltage profile when charging.  AGMs are more sensitive to the voltage than FLA is.  I ended up with a balmer 614 regulator and a Sterling charger.  Both have programmable bulk and float voltages. And the Balmer measures the voltage at the battery not at the alternator.  

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094

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You might have a lot of voltage drop between the battery and the alternator.  Or your alternator may be getting hot and lowering its output.  Or The voltage regulator might be set too low. I'm sure there may be more but I would check that first.  

When I was looking at how to extend the life of my AGMs one of the key things was the voltage profile when charging.  AGMs are more sensitive to the voltage than FLA is.  I ended up with a balmer 614 regulator and a Sterling charger.  Both have programmable bulk and float voltages. And the Balmer measures the voltage at the battery not at the alternator.  

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094

rtrinkle
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Thanks for the info. I know the belt tension is good. Cable from alt to bat is 1/0 cable. Don't think we are having voltage drop issue. The alt only has the batt sense connection. There is no "regulator", so the alt might be getting too hot.

with the Motorola 55amp alt, can a regulator be installed?  If the alt is still good, I don't want to have to replace that as well. At that point it might be cheaper to add solar. I'll also check the alt voltage and current when running. 

Again, thanks for the info, I'll post my findings. I'll be there again next weekend. 

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

LeslieTroyer
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rtrinkle wrote:
There is no "regulator", so the alt might be getting too hot.

with the Motorola 55amp alt, can a regulator be installed? . 

There is always a regulator. Yours is internal to the alternator.  Some internal regulators have a voltage adjustment pot.   

Les

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094

clennox
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13.5 sounds low. First thing I'd look at is the belt tension. Make sure it's not loose. Next get a known good volt meter and check again the voltage output. I think it should be around 14.2.

Check for any wiring problems. I have seen loose and broken wires at the Alt.
​If all looks good and you don't have a good way to test the amp output, take it to a Alt repair shop and have it tested.
​PS. If it NG. Don't buy one of those cheap Chinese replacements.

Chuck Lennox
97 MKii Ventura Ca
Island Girl Hull #1611

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.

Chuck Lennox
97 MKii Ventura Ca
Island Girl Hull #1611

rtrinkle
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Thanks for the info. Just changed the belt, so pretty sure is not the tension. I'll double check the V output an amp output. I was just going by memory when posting.

if it's a heat issue can a voltage regulator be used with a 55 amp Motorola alt?  I know the alt has a P Sense connection. That is all that is sensing the voltage currently. If I'm having issues with the alt, would it be better to replace, or is it worth repairing?  I've never changed the alt, and Not sure what to do with the pulleys if the alt pulley needs a different belt than the V belt. Then there is schimming for alignment. Just sound like headache of work that I haven't done before, and there is no service men in the area of the marina. And there are no parts stores in the area either. 

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

danno
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If you don't have an external regulator, then there is one built inside of the alternator.  The "P" terminal is usually a "pulse" or "phase" terminal for a tach.  I would manually check the voltage at the B+ (large stud the alternator cable connects to).  I assume you were running at normal 'cruising' RPMs for 6 hours?  Alternators generally don't recharge well at idle as increased amperage is available at higher RPM.  At idle, they are generally rated to maintain operating system loads and may recharge very slowly, especially with a high ah battery bank.

13.5 volts doesn't sound terribly low, as most alternators charge between 13.8 and 14.6 volts at idle and most off the shelf multimeters are between 2-5% accuracy within the range setting (so if you're set to the 20VDC range it could be +/- 0.4V), and panel gauges can be even worse. I would check to be sure the terminals are clean and tightened properly, as well as all your negative connections between the alternator and the batteries.  As most alternators 'ground' through the alternator frame, you want to make sure that the contact between the alternator and its mount and the alternator bracket to the engine is good as well. 

It's not unusual for hard to troubleshoot alternator problems to end up being a grounding issue, as the negative side of the circuit is kind of "out of sight and out of mind".  A quick rundown with a wire brush and a wrench may be all that's needed (alternator bracket, engine ground cable, etc).

As far as heat is concerned, that can make a slight problem worse, as dirty/loose connections create resistance and resistance creates heat and robs voltage.  Add to that that heat increases resistance and a small/simple problem amplifies itself.

If it's showing 13.5 volts at the battery while running, not charging, you were at normal RPM and the belt isn't slipping, the alternator may be getting weak.  Then I'd take it to a good auto-electric shop and have it tested. They can generally rebuild them competitively to the price of new, but often with better quality.  If not, a proper replacement (same p/n or equivalent) should be available with the same frame size and pulley profile to avoid shimming for alignment.

Dan & Amanda Reed
1989 Catalina 36 #947 Miss America
Fin Keel Std Rig
FL Panhandle

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Don't overlook the possibility of a fault in the ground path back to the engine.

Matthew Chachère
s/v ¡Que Chévere! #466
1985 C36 MKI tall rig fin keel M25
Homeported in eastern Long Island, NY

rtrinkle
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Thanks for the info. I'll definitely check the connections and ground. I currently use the P sense terminal for the regulation. I'll also check the V again while running. I typically run at 2000 and 2500 Rpm.  This was the case this time. I'll also check ground at the engine. I'll let you know the findings once complete. 

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

Maine Sail
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#1 How are you determining 60% SOC?

#2 Who installed the battery monitor and shunt?

#3 Did the battery monitor show any charge current from the alternator?

#4 If battery terminal voltage was 13.5V, charging was occurring. Did you check alt output with a clamp meter?

#5 A 55A stock alternator is simply not well suited for charging AGM batteries. This should be addressed or the AGM's will suffer.

#6 I would strongly advise against converting any Motorola or Leece-Neville 8MR series alternator, below the 90A models, to external regulation. AGM batteries need and deserve proper charging or they can quickly be destroyed $$$$$$. For an AGM PSOC use battery (partial state of charge/off-grid/marine) this means a minimum charge current of about 20% of Ah capacity, temp compensated charging, proper absorption duration programming and programming the regulator for the high end of the absorption charging voltages specified by the battery manufacturer. Permanent damage from undercharging AGM batteries can occur in as little as 10-30 days of under charging use. For example a Lifeline AGM, when charged from 50% SOC, must attain 14.4V (at the battery terminals) during charging then be held at 14.4V for a at least 3.5 +/- hours to get anywhere close to 100% SOC.

#7 Most Motorola & Leece-Neville 8MR style alts can be converted, see article here but converting a 55A model is about as worthwhile as walking up hill on ice wearing Mickey Mouse slippers.....

#8 AGM batteries should be installed as a system and the system design & infrastructure should be done or in-place before the AGM's are installed. I regularly see thousands and thousands of dollars in AGM's destroyed in under two years due to improper charging, installation and by not using a "system" approach.

______

rtrinkle
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1. The 60% SOC is from the batt monitor. 
2.  I installed the batt monitor and shunt, its from Victron Energy. 
3.  Yes, and this is also an update for the other replies, voltage at the batt mon while engine running is 14.2 -14.3 vdc. 
4.  I have not used the clamp to measure amp from the alt. 
5-8.  Great info. I have decided to upgrade the alternator, despite the $$$$$$$.   I was thinking of a balmar  alternator package that comes with a regulator. Probably the 105 amp. I suspect this would be a good setup?  Are the balmars pretty straight forward to install?  

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

Maine Sail
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Quote:
1. The 60% SOC is from the batt monitor.

If there was a charging level voltage the shunt/monitor should have been showing some change in charge current.

Quote:
2.  I installed the batt monitor and shunt, its from Victron Energy.

It is possible something is miswired. The only thing that should be on the battery side of the shunt is the house battery negative terminal. Start battery and every other negative lead on-board should be on the load side of the shunt...

Quote:
3.  Yes, and this is also an update for the other replies, voltage at the batt mon while engine running is 14.2 -14.3 vdc.

Then you should definitely be increasing the SOC...

Quote:
5-8.  Great info. I have decided to upgrade the alternator, despite the $$$$$$$.   I was thinking of a balmar  alternator package that comes with a regulator. Probably the 105 amp. I suspect this would be a good setup?  Are the balmars pretty straight forward to install?  

The Balmar packages are a good deal vs. buying everything separately. Balmar does not make a 105A alternator though. They do a 70A, 100A, 120A & 150A in a 6 series.. Alternators are pretty easy to install but no performance alternator is truly "drop in" and they almost always require alignment, shimming, different belt etc...

Be sure who you buy from actually knows what they are doing, most don't and are nothing more than order takers, and they will be happy to ship you a package with a 1/2" pulley when you really need a 3/8" etc. etc... A Balmar 100A 6 series package starts at under $900.00 with an ARS-5 regulator and temp sensors.

______

rtrinkle
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Has anyone installed the 100 amp balmar on an Universal M35a?  I'm looking at the 621-100-SV alternator. Looks like a 2 inch foot on the alternator.  Right now, I have a 3/8" belt. Would a 1/2" belt work on the pulleys on the pump and crank shaft?  I didn't look at that. 

Any infomation on on the installation would be helpful. I'm using the existing 1/0 gauge wire directly connected to the 400 amp house AGM house bank. 

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

LeslieTroyer
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I doubt you could get a half inch grove on the crank pulley for the M35.  They do make serpentine kits that should be good for 150+A.  100A is the limit for 3/8".   Maine Sail also has some nice 100+A alternators for our universal motors at his website marinehowto.com. 

Les

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094

rtrinkle
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So, I have looked more carefully at the present alternator on the M35A.  I found a label on the bottom that says Prestolite 8LM2017KA with a 8RC2008a regulator on the back of the alternator.  It is a 51 amp 12 volt alternator.  I did a charging test with the alternator. 
Test 1- checking voltage when engine was first started and shore power disconnected.  Batt. monitor reads 14.2 volts. 
Test 2 - I spend the night on the hook, played the stereo for about 6 hours, and charging mobile devices all night. Started the engine the next morning, and the batt monitor reads 13.5 volts while charging.  Did a amp reading with the clamp style meter from Ancor, and it read 30+ amps  charging at first startup.  Went back 2 hours later and it read 6-8 amps charging.  So I suspect the alternator charging, just working way to hard, and possibly overheating, keeping it from charging for long periods of time.

So the next question is what alternator to go with.  While the Balmar 100a looks great, it is a bit out of my price range, (daughter just got engaged).  So I'm looking for a less expensive alternative.  I've read posts here about the Leech-Neville 8MR2069TA with an 8RG2043 regulator, with engines other than the M35A / AC.  

I'm also looking for ease of installation.  Hoping to get a alternator that is more of a drop in alternator that will not require alot of work to get installed and aligned, and I can use my 3/8" belt. I'm pretty mechanical and electrically inclined, but my marina is in the middle of nowhere and about 30 minutes to the closest hardware store.  Don't really want to make it a month long project, and not have use of the boat.

Any suggestions greatly welcomed.

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

LeslieTroyer
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I used th 8MR that is shown in MaineSail's article on converting to external regulation.  Be sure and get it with a 3/8 pulley - it took me a bit to sourceone as the shaft diameter was not common.  I'm sure there are compatible models with 2" foot but I got a 1" foot and used an adapter.  Be sure the long mounting bolt is the correct diameter.  Universal/Catalina supplies the wrong size in their alternator bracket kit.  The expensive part is the regulator. You need a good smart one that has alternator and battery Temp com pension.  The small motor switch is also helpful if you need to power thru big current or waves.  

Les

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094

rtrinkle
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If you are using the 8mr2069ta, what regulator are you using, and what diameter mounting bolt did you use?  Also, what was the shaft diameter?  Can you explain the small motor switch you mentioned?

ive been researching the prestolite I have now, and can't find any information on it. 

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

LeslieTroyer
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I'm using a Balmar 614.   The small motor switch that connects to the regulator, it cuts the max amperage delivered in half so if you have a 100A alternator it will cut it to 50A max.  This cuts the load on the engine so the power can be used for propulsion.

I don't remember the diameter of the bolt( think it was metric), but there should be no slop between the hole in the bracket/alternated and bolt.  The 1" foot extension kit comes with a sleeve if the alternator hole is big relative to the bracket (I didn't need it).  

I believe the alternator pulley shaft diameter is 17mm,  the alternator shaft is cut for a keyway but my pulley doesn't have one and still holds great .  If you are going to get pulley and alternator separately you need to fine a big impact driver (mine is 1/2" air driven). 

Also after changing out any alternator it's a good idea to recalibrate your tach. If you are a paid member here an optical tach is part of the tool lending benefit, or they are under $40 at Harbor Freight.

If if I had to do it again I would get the alternator vendor to pop on the right sized machined (not stamped) pulley.  I didn't because I was trying to save $30 and reuse the one I had (which turned out to be the wrong diameter).   

HTH
Les

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094

rtrinkle
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I ordered the 105a alternator and ars-5h regulator. Where do you connect the ignition wire for the regulator? I was thinking to connect it to the fuel pump.  And where did you mount the regulator?

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

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IIRC I wired to the hot side not the switched side of the power, at a terminal strip located on the port firewall. All the wires from the harness terminate here ( trailer plug removed).  I don't have the typical A/B/Both switch but a three on/off switch setup that MaineSail has recommended. So my engine electrical is only turned on when I'm using the engine. If you have the standard wiring I'd go to a switched source I believe the purple alternator excite is where you should connect. Below is a sideways picture of the mounted regulator. I remover it being a pain to fish these wires because of the very small space the come out into.   Don't cut the ring off the temp sensor (it's got the thermistor in it) and be sure to fuse the voltage sense wire within 7" of the battery. 

Les

 

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094

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rtrinkle
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​My current electrical has 2 house batts in parallel, 1 start batt.  Alternator directly connected to house bank, starter directly connected to start bank.  Attached is the schematic of my current electrical setup. My house bank has 150A fuze on the positive terminal.

Being pretty new to alternators, the excite is always on when the ignition key is turned to the on position, not just the starting position?  Could I connect to the alt sense as well for the tach?

I've been reading the manual for the ARS-5, is says to connect the it to the oil sensor.  I'd rather not cut splice into a unbroken circuit, but if I could put a ring terminal on it to connect to a post, it would be better.

​Looking at your pic, is that the aft cabin or the galley next to the engine compartment?  Your boat is a bit different than mine, being a 1995 MKII.

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

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LeslieTroyer
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Yes the alternator excite should come on with the switch in the on position.  The alternator sence is for measuring the voltage at you batteries so it wouldn't go to the tach. The tach gets its signal from one of the two unrectified stator outputs. 

Generators/Alternators generate electricity by spinning a coil of wire inside a magnetic field. Generators have big permanent magnets that create the[magnetic] field.  Alternators generate the field by supplying voltage to as second set of coils (this is somewhat simplified but a good generalization).  This is why in the dark ages of my youth you could push start a completely dead car with a generator but not the same car with an alternator.   

I personally wouldnt pull power power from any sensor, the drain is probably very small and won't effect the reading very much but I would always wonder how much.   You should have a switched power going to your current alternator I don't see why you can't use it.  As for your tach, the unrectified tap on the alternator (either one doesn't matter) goes to my regulator and the regulator feeds the tach signal.  The ar5  may be different but this is done to always keep a tiny field voltage on the alternator so the tach can get a signal. If you are completely charged and not drawing any power they would normally turn off the field voltage stopping the alternator output.  No output no signal to the tach.   Remember those coils on the field and stator??  Well on modern engines they actually have multiple coils for the field and multiples for the stator. If you go from an alternator with 6 coils to one that has 12 coils the ac frequency doubles and assuming the same pulley arrangement your tach will read twice the engine speed. Thus my recommendation for calibrating the tach earlier.  

Yes that is the engine cover to the left of the photo (looking aft)   My regulator is on the bulkhead between the galley and aft berth.  I put it here so I could more easily read the status led and make programming it easier. 

There are a couple of things from your drawing. I'm not saying what you have is wrong but ther may be a better/different way.  1) your chargers, windlass...  should be on.the other side of the shunt.  Your boat monitor needs to see all additions and subtraction to the batteries.  The negative battery should go directly to the shunt with no sneaker wires in between.  2) I suspect that your chargers (shore and solar) are smaller than a #4 wire thus need to be fused at the battery side to protect those smaller wires.  You might read my article in the current Mainsheet. If you don't get it becoming a Member here (dues paid).will get you the magazine for "free"

Im really glad you have a wire diagram like you posted. It can really help when troubleshooting.  
 

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094

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OK - I haven't read this thread thoroughly yet but if the Voltage at the monitor is 14.2 when the engine is running and the charge SOC is not increasing - something is wrong in the shunt circuit. And while I agree that our 55 amp Motorola alternators are not a good solution for the AGM battery charging, you may be throwing money at a problem that should be easy to fix.
Looking at your diagram - the shunt is wired incorrectly.  ALL the ground leads must be terminated on the terminal to the right in your schematic. If not - the monitor is not reading the charging current.
You need to decide which battery you want to monitor (only one for SOC and one voltage only) if you have the two battery model BMV-702.  All negative terminals for the monitored battery MUST be on the terminal away (so to speak) from the terminal connected to the battery negative terminal.  That way ALL monitored current goes through the shunt!
Maine Sail has an excellent video on this issue on this web site showing the connections in detail.
I used that as a guide to connect my monitor and it works great.
https://forums.sailboatowners.com/index.php?threads/wiring-installing-a-...

_____________
Harold Baker
S/V Lucky Duck
Sandusky Ohio, Great Lakes
1989 C-36 mkI TR/WK M25XP

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Great information from both of you.  Which brings up some comments/questions regarding your posts.
Les-
1."Yes the alternator excite should come on with the switch in the on position." 

So I should be able to connect the regulator ignition to the alternator excite to provide power when ever the key is in the on position, not the start position?

2. "I personally wouldnt pull power power from any sensor". 

Makes a lot of sense, thanks.

3."your chargers, windlass...  should be on.the other side of the shunt.  Your boat monitor needs to see all additions and subtraction to the batteries"

This makes sense, I will need to look and see if all these negs terminals will fit on that side of the shunt.  I suspect I would still need the house bank also connected directly to the main engine ground, as well as the alternator?

4. "The negative battery should go directly to the shunt with no sneaker wires in between."
That is the case, neg from the house bank goes directly to the shunt.  That is the only wire connected to the shunt on that side.

5.  "I suspect that your chargers (shore and solar) are smaller than a #4 wire thus need to be fused at the battery side to protect those smaller wires."

Solar is fused, sorry if that wasn't clear in the diagram.  Shore power is 2 ga. wire

Harold-
1.  "I haven't read this thread thoroughly yet but if the Voltage at the monitor is 14.2 when the engine is running and the charge SOC is not increasing - something is wrong in the shunt circuit. And while I agree that our 55 amp Motorola alternators are not a good solution for the AGM battery charging, you may be throwing money at a problem that should be easy to fix."

I did make an adjustment of a future post here, 14.2 is only seen when engine is started immediately after disconnecting shore power.  After a night on the hook, and starting the engine, voltage was 13.5.

2. Looking at your diagram - the shunt is wired incorrectly.  ALL the ground leads must be terminated on the terminal to the right in your schematic. If not - the monitor is not reading the charging current.

I will defintely look into this, and see if the shunt will accept all the negatives.  Does this include charger, windlass, solar, alternator?  When I talked to MaineShip, he stated the house bank should be directly connected to the engine ground as well, and the new alternator should also be connected to the engine ground.  If so, can the shunt be extended, with something like another bus bar, and still get accurate readings?

3. "if you have the two battery model BMV-702.  All negative terminals for the monitored battery MUST be on the terminal away (so to speak) from the terminal connected to the battery negative terminal" 

Yes, I have this model, monitoring SOC for the house bank.  Start batt only gets voltage monitored.  So reading these comments, and listening to MaineShip, I should have 2 negatives connected to the house bank: one to the shunt (left side), and one to ground on the engine?  If so, I ask the question again, can the shunt be extended, with something like another bus bar on the right side, and still get accurate readings (in computer terms like a hub)?  Guess I'll call Victron again, as they might have been some communication lost with them.

I've already pulled the trigger on the alternator and regualtor, so that is a project I've been wanting to do for some time, but I might be adding a bit of rewiring to the project scope.

I love this site, and thank you all for you comments.  Definitely a constructive conversation, in which, I have learned alot.  Keep them coming...

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

Maine Sail
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rtrinkle wrote:

I will defintely look into this, and see if the shunt will accept all the negatives.  Does this include charger, windlass, solar, alternator?  When I talked to MaineShip, he stated the house bank should be directly connected to the engine ground as well, and the new alternator should also be connected to the engine ground.  If so, can the shunt be extended, with something like another bus bar, and still get accurate readings?

and listening to MaineShip, I should have 2 negatives connected to the house bank: one to the shunt (left side), and one to ground on the engine?  If so, I ask the question again, can the shunt be extended, with something like another bus bar on the right side, and still get accurate readings (in computer terms like a hub)?  Guess I'll call Victron again, as they might have been some communication lost with them.
 

ALL NEGATIVES from the vessel MUST be on the LOAD side of the shunt. This includes;

Start Battery Neg
Engine Negative
Alternator Negative
Regulator Negative
DC Panel Negative
Windlass Negative
Charger Negative
Solar Negative
etc. etc...

The only items that can be before a shunt would be a battery temp sensor (no current drawn) or a SmartGauge negative. The shunt can't even read the SmartGauge's load, not enough resolution, and it needs a direct connection for its accuracy.

You extend a shunt like this, by using a busbar:

Please ignore the wing nuts, and please, do not use them, this shot was taken before I stuffed the rest of bank in there so you could actually see what's going on with the shunt wiring.

______

rtrinkle
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Alrighty,, I just purchased a 150 amp buss bar to connect to the load side of shunt. I figured that would be big enough, as the fuse on the battery is 150 amp.  I will rewire the negative side before installing the alt.  Guess the next question is where to connect the brown ignition wire on the regulator?  According to Balmar, this need to be connected to a small power source that will always be on when the key is in the on position, and always off when key is in Off position.  I was thinking of connecting it to the electric fuel pump.  Mainly because there is no buss bar for the engine wires that go to the pedestal and gauges.  It is just wires.

Also, is it okay to connect the negative on the alt to the ground on the engine? And have the ground on the engine, already in place, run to the negative bus bar?  Therefore, providing neg connection between the alt and bus through the neg cable from the engine ground?  Or do I need to connect negative on the alt to the bus bar, then provide another cable from neg on alt to engine ground, and still keep the neg from the bus bar to the engine ground?  I know this is splitting hairs, but just want to do it correctly.

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

Maine Sail
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rtrinkle wrote:
Guess the next question is where to connect the brown ignition wire on the regulator? 

You wire it to the ignition switches "load" side...

rtrinkle wrote:
Also, is it okay to connect the negative on the alt to the ground on the engine? And have the ground on the engine, already in place, run to the negative bus bar?  Therefore, providing neg connection between the alt and bus through the neg cable from the engine ground?  Or do I need to connect negative on the alt to the bus bar, then provide another cable from neg on alt to engine ground, and still keep the neg from the bus bar to the engine ground?  I know this is splitting hairs, but just want to do it correctly.

Please do not use any part of the engine as your DC circuit path unless you actually want to induce voltage drop.... Physically stack the alternator negative lug on-top of the engines negative lug. It is okay to use the busbar as a circuit path, though with a 150A busbar I would still suggest stacking the alt neg to engine neg for the best low resistance path...

______

rtrinkle
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Just want to make sure I'm not second guessing anything.  The picture attached shows the negative connections as I think I am understanding.  Is this correct?  Please correct me if I am wrong.

Robert Trinkle
Troubador, 1995 C36 MKII #1433, SR/WK
Universal M35A
Kinsale Harbor Marina
Kinsale, VA

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